Imaging Pearls ❯ Small Bowel ❯ Malignant Tumors
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- “Mesothelioma has been linked to toxic exposure to industrial pollutants, especially asbestos. The most common site is the visceral pleura, followed by the peritoneum. Because pleural mesothelioma is more common than malignant peritoneal mesothelioma (MPM), most research has been on the pleural variant. The assumption has been that mesothelioma in the peritoneum would be biologically similar to the pleura, but some differences have been found. MPM commonly presents with diffuse, extensive spread throughout the abdomen with rare metastatic spread beyond the abdominal cavity.”
Malignant peritoneal mesothelioma: a review.
Kim J, Bhagwandin S, Labow DM.
Ann Transl Med. 2017 Jun;5(11):236 - “Mesothelioma has been linked to industrial pollutants and mineral exposure. The most common carcinogen identified for pleural mesothelioma has been asbestos, with approximately 80% of cases linked to asbestos exposure. While asbestos is also the best defined risk factor for MPM, the link is weaker. Only 33–50% of patients diagnosed with MPM report any known prior exposure to asbestos. Time and duration of exposure do not directly correlate with disease development, with some long-term exposures yielding no disease while some short-term exposures leading to significant tumor burden.”
Malignant peritoneal mesothelioma: a review.
Kim J, Bhagwandin S, Labow DM.
Ann Transl Med. 2017 Jun;5(11):236 - “On CT, MPM appears as a solid, heterogeneous, soft tissue mass with irregular margins that enhances with the use of intravenous (IV) contrast. MPM tends to be more expansive than infiltrative so diffuse distribution throughout the abdominal cavity should raise suspicion. The lack of a primary site with neither lymph node involvement nor distant metastases helps differentiate MPM from other intra-abdominal malignancies . Ascites is found in 60–100% of patients that are newly diagnosed. Other findings include caking, thickening or masses in the omentum, mesenteric nodules, peritoneal thickening, diaphragmatic involvement, scalloping of the intraabdominal organs such as the liver and spleen, and loculated ascites.”
Malignant peritoneal mesothelioma: a review.
Kim J, Bhagwandin S, Labow DM.
Ann Transl Med. 2017 Jun;5(11):236 - “MPM can be difficult to diagnose based solely on histologic patterns, making immunohistochemical markers important in diagnosis. No single immunohistochemical marker is specific for MPM. Instead, panels of markers are used to differentiate MPM from other more common tumors that can have similar histologic features. MPM stains positive for EMA, calretinin, CK 5/6, WT-1, mesothelin, and antimesothelial cell antibody-1, and negative for carcinoma markers CEA, Ber-EP4, LeuM1, and Bg8 thyroid transcription factor-1, and B72.3. These markers help differentiate MPM from primary papillary serous carcinoma of the peritoneum, serous ovarian carcinomas, colorectal adenocarcinoma involving the peritoneum, and borderline serous tumors. The current recommendation is to use two mesothelioma markers and two carcinoma markers.”
Malignant peritoneal mesothelioma: a review.
Kim J, Bhagwandin S, Labow DM.
Ann Transl Med. 2017 Jun;5(11):236 - “MPM is a very rare disease of peritoneal surfaces which is diagnosed less frequently than the pleural variant. Advances have been made in treatment, with CRS-HIPEC as first-line therapy in those with favorable factors. While systemic chemotherapy has been shown to be effective, further advancements in systemic therapy are likely to be found in targeting molecular pathways. Investigations into this treatment modality are underway and are promising for providing better survival for this disease which is currently ultimately fatal due to its aggressive extensive peritoneal spread.”
Malignant peritoneal mesothelioma: a review.
Kim J, Bhagwandin S, Labow DM.
Ann Transl Med. 2017 Jun;5(11):236
- Hypervascular metastatic and lymphoproliferative disorders can cause high attenuation lymphadenopathy due to intranodal hemorrhage (on unenhanced CT) or hyperenhancement (on contrast-enhanced CT):
- Kaposi sarcoma
- papillary thyroid carcinoma
- Castleman disease
- Kikuchi-Fujimoto disease
- Kimura disease
- angioimmunoblastic T cell lymphoma
- neuroendocrine tumors
- renal cell carcinoma
- “Melanoma is the most aggressive form of skin cancer, with tendency to spread to any organ of the human body, including the gastrointestinal tract (GIT). The diagnosis of metastases to the GIT can be difficult, as they may be clinically silent for somewhile and may occur years after the initial melanoma diagnosis. CT imaging remains the standard modality for staging and surveillance of melanoma patients, and in most cases, it will be the first imaging modality to identify GIT lesions. However, interpretation of CT studies in patients with melanoma can be challenging as lesions may be subtle and random in distribution, as well as sometimes mimicking other conditions. Even so, early diagnosis of GIT metastases is critical to avoid emergency hospitalisations, whilst surgical intervention can be curative in some cases. In this review, we illustrate the various imaging presentations of melanoma metastases within the GIT, discuss the clinical aspects and offer advice on investigation and management. We offer tips intended to aid radiologists in their diagnostic skills and interpretation of melanoma imaging scans.”
The different faces of metastatic melanoma in the gastrointestinal tract
Eva Mendes Serrao et al.
Insights into Imaging (2022) 13:161 - • Melanoma is the most common solid tumour metastasizing to the GIT.
• Melanoma metastases in the GIT can have multiple radiological appearances and mimic other conditions.
• Radiological identification of melanoma metastases in the GIT is important, as early diagnosis and treatment improve quality and quantity of life, even inpalliative cases.
The different faces of metastatic melanoma in the gastrointestinal tract
Eva Mendes Serrao et al.
Insights into Imaging (2022) 13:161 - “Melanoma in the GIT can also rarely be a true primary tumour arising from the GI mucosa, with this entity being biologically distinct from cutaneous melanoma. In the GIT, they arise most frequently in the anorectal mucosal epithelium (anus 31% and rectum 22%), and less often in the oesophagus (6%), stomach (3%), small intestine (2%) and large intestine (1%), with a high proportion arising in the mucosal linings of the oralnasopharynx(35%).”
The different faces of metastatic melanoma in the gastrointestinal tract
Eva Mendes Serrao et al.
Insights into Imaging (2022) 13:161 - “The stomach, after the small bowel and colon, is the third most common GIT site involved by MM. Patients with MM in the stomach can present with nausea, vomiting, gastrointestinal bleeding, weight loss and occasionallwith acute perforation. CT imaging can suggest the diagnosis by the presence of a mural nodule or mass , with or without cavitation, but definitive diagnosis is best achieved by endoscopy and biopsy. However, there is growing evidence that MRI with diffusion weighted imaging (DWI) can provide improved early detection and characterisation of gastric lesions as well as local staging.”
The different faces of metastatic melanoma in the gastrointestinal tract
Eva Mendes Serrao et al.
Insights into Imaging (2022) 13:161 - “The small bowel is the most common metastatic site for melanoma in the GIT. Melanoma is the most common solid cancer type to metastasise to the small bowel (SB) with the jejunum and terminal ileum being the most commonly involved segments.”
The different faces of metastatic melanoma in the gastrointestinal tract
Eva Mendes Serrao et al.
Insights into Imaging (2022) 13:161 - “Melanoma metastases to the GIT are not uncommon. Oligometastatic lesions can be successfully removed by surgery and offer cure to selected patients, even those whose tumours occur during treatment with modern systemic therapy. CT remains the standard modality for detection, staging and follow-up of these patients. However, detection of GIT metastases can be challenging as they are often subtle, can be multiple and can present with a multitude of morphological appearances.”
The different faces of metastatic melanoma in the gastrointestinal tract
Eva Mendes Serrao et al.
Insights into Imaging (2022) 13:161
- Different small bowel (SB) imaging patterns have been associated with metastatic melanoma (MM). More frequently, it presents with polypoid nodules causing intussusception, and less frequently as ulcerating mural nodules, exo-enteric lesions, infiltrating masses or serosal deposits. Aneurysmal dilatation is a rare presentationwith only a single case previously reported in the literature to the best of our knowledge. This appearance is defined as a cavitary dilatation of the intestinal lumen (> 4 cm) with a nodular, irregular luminal contour and peripheral bowel wall thickening and was first described as an imaging finding characteristic of lymphoma. However, it has subsequently been associated with other cancer types, including primary SB adenocarcinoma,leiomyosarcoma, gastrointestinal stromal tumours, and metastatic disease from non-small cell bronchogenic carcinoma, adenocarcinoma of the rectum and endometrial stromal sarcoma , as well as with amyloidosis .
The forgotten appearance of metastatic melanoma in the small bowel
Eva Mendes Serrao et al.
Cancer Imaging (2022) 22:27 https://doi.org/10.1186/s40644-022-00463-5 - “Gastrointestinal spread from MM is relatively common, with the SB representing the most common site of involvement. However, SB involvement is still vastly underappreciated clinically, with studies reporting the presence of lesions in 43.5–60% of cases postmortem, but only 1.5–4.4% antemortem. SB melanoma metastases are frequently multiple, due to haematogenous dissemination, and preferentially affect the terminal ileum and jejunum As in our reported cases, SB metastases are more common with cutaneous as opposed to non-cutaneous melanomas. Primary mucosal melanomas arising in the SB are rare, remaining a controversial diagnosis as the possibility of a MM from an unidentified or regressed primary cutaneous melanoma should always be considered.”
The forgotten appearance of metastatic melanoma in the small bowel
Eva Mendes Serrao et al.
Cancer Imaging (2022) 22:27 https://doi.org/10.1186/s40644-022-00463-5 - "Interpretation of staging CT studies of patients with MM can be challenging given the need for a thorough review of the scans and unpredictable metastatic patterns with this disease. Nevertheless, the bowel is an important review area in these patients, particularly in the case of primary cutaneous melanoma arising in the head and neck region, trunk and lower extremity. On the other hand, when a SB lesion is incidentally identified on imaging, one should always consider the possibility of MM, and careful medical history should be taken regarding prior history of primary skin lesions.”
The forgotten appearance of metastatic melanoma in the small bowel
Eva Mendes Serrao et al.
Cancer Imaging (2022) 22:27 https://doi.org/10.1186/s40644-022-00463-5
- "The clinical presentation of SB MM is usually non-specific, including a constellation of symptoms associated with GI tract pathology, including abdominal pain, unexplained weight loss, iron-deficiency anaemia, change in bowel habit and GI bleeding, though a large proportion may be asymptomatic. Metastases are more frequent in the SB than primary tumours and may occur by haematogenous spread, local extension or intraperitoneal seeding. Melanoma is the most common cancer type to metastasize to the SB , occurring either at the time of initial diagnosis, or not uncommonly several years after the primary malignancy has been treated(average of 7.2 years).”
The forgotten appearance of metastatic melanoma in the small bowel
Eva Mendes Serrao et al.
Cancer Imaging (2022) 22:27 - "Recognition of unusual radiological signs of SB spread from MM, like aneurysmal SB dilatation, is important to expedite diagnosis, provide appropriate treatment, and consequently improve quality of life and likely survival of these patients. As the most common cancer type metastasizing to the SB and as a known imaging mimicker, MM should remain in any radiologist’s differential diagnosis for SB lesions. Not uncommonly, there are other imaging features which can help make the correct diagnosis.”
The forgotten appearance of metastatic melanoma in the small bowel
Eva Mendes Serrao et al.
Cancer Imaging (2022) 22:27
- Rosai-Dorfman disease is a rare disorder characterized by overproduction (proliferation) and accumulation of a specific type of white blood cell (histiocyte) in the lymph nodes of the body (lymphadenopathy), most often those of the neck (cervical lymphadenopathy). In some cases, abnormal accumulation of histiocytes may occur in other areas of the body besides the lymph nodes (extranodal). These areas include the skin, central nervous system, kidney, and digestive tract. The symptoms and physical findings associated with Rosai-Dorfman disease vary depending upon the specific areas of the body that are affected. The disorder predominantly affects children, adolescents or young adults. The exact cause of Rosai-Dorfman disease is unknown.
- Rosai-Dorfman disease was first described by Rosai and Dorfman in 1969. It is a benign disease which is characterized by over-production and accumulation of a specific type of white blood cell (histiocyte) in the lymph nodes of the body, most often those of the neck (cervical).Other lymph node groups may also be involved and, in some cases, abnormal accumulation of histiocytes may occur in other areas of the body (extranodal).The cause of this condition remains unknown, although altered immune responses and infectious agents may play a role. Rosai-Dorfman disease is a self-limited and seldom life-threatening disease which commonly does not require therapy.
- The symptoms and physical findings associated with Rosai-Dorfman disease vary depending upon the specific areas of the body that are affected. Systemic symptoms, such as fever, weight loss, malaise, joint pain, and night sweats, may be present. Cervical lymph nodes are most characteristically involved, but other areas, including extranodal regions, can be affected. These areas include the skin, central nervous system, kidney, and digestive tract.
- “Rosai-Dorfman disease (RDD), also referred to as sinus histiocytosis with massive lymphadenopathy, is a rare, idiopathic, non-Langerhans-cell, histiocytic proliferative disorder of unknown etiology. RDD is histologically characterized by a nonmalignant proliferation of distinctive histiocytic/phagocytic cells within lymph node sinuses and lymphatics in extranodal sites. The proliferative histiocytes have abundant pale to slightly eosinophilic cytoplasm often containing lymphocytes and plasma cells within, a phenomenon variously known as emperipolesis or lymphocytophagocytosis. Although classical RDD usually presents as massive, painless, bilateral neck lymph node enlargement, approximate 40% of RDD cases documented to date present in extranodal organs or tissues, in some without associated lymphadenopathy which may or may not develop later in the disease course.”
- “Although classical RDD usually presents as massive, painless, bilateral neck lymph node enlargement, approximate 40% of RDD cases documented to date present in extranodal organs or tissues, in some without associated lymphadenopathy which may or may not develop later in the disease course.”
Extranodal Rosai-Dorfman disease involving appendix and mesenteric nodes with a protracted course: report of a rare case lacking relationship to IgG4-related disease and review of the literature
Ming Zhao et al.
Int J Clin Exp Pathol. 2013; 6(11): 2569–2577. - "Gastrointestinal tract seems to be the least commonly involved site by RDD and represents less than 1% of extranodal presentations. In 2000, Lauwers et al reported to date the largest series of eleven cases of RDD involving the digestive system that included five cases arising within the intestinal tract, and to our knowledge, including the current one, only 15 cases of gastrointestinal RDD have been reported in the English literature to date.”
Extranodal Rosai-Dorfman disease involving appendix and mesenteric nodes with a protracted course: report of a rare case lacking relationship to IgG4-related disease and review of the literature
Ming Zhao et al.
Int J Clin Exp Pathol. 2013; 6(11): 2569–2577. - “This large retrospective series shows that abdominal pain and peritoneal or mesenteric tumours may reveal or be associated with histiocytosis. We emphasize the fact that histiocytosis is a rare diagnosis to be made, but in those cases where the most common diagnoses for a mesenteric mass have been excluded, histiocytosis is a possibility to take into consideration. We suggest that a PET scan may ease this process of diagnosis by revealing secondary localization of histiocytosis. The majority of our patients were initially misdiagnosed and there was an important time delay. Molecular analysis is a major diagnostic tool to confirm the diagnosis. Once the diagnosis of ECD is achieved, targeted therapies may be highly efficient even in those cases with peritoneal localization.”
Peritoneal or mesenteric tumours revealing histiocytosis.
Cohen-Aubart F et al.
BMJ Open Gastroenterol. 2021 May;8(1):e000622. - "Primary tumors arising in the mesentery are relatively rare. On the other hand, the mesentery is a frequent avenue of spread for malignant neoplasms through the peritoneal cavity and between the peritoneal spaces and the retroperitoneum. Patients with mesenteric neoplasms usually present with nonspecific symptoms of abdominal pain, weight loss, a palpable abdominal mass, or diarrhea. CT plays a critical role in achieving an accurate diagnosis of these neoplasms to guide patient management."
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheth S, Horton KM, Garland MR, Fishman EK
RadioGraphics Mar 2003, Vol. 23, No. 2:457–473
- Gangliocytic paraganglioma (GP) is an extremely rare benign tumor that commonly arises from the second part of the duodenum. Since GP exhibit neither prominent mitotic activity nor Ki-67 immunoreactivity, this tumor is often misdiagnosed as neuroendocrine tumor (NET) G1 (carcinoid tumor).
Gangliocytic paraganglioma: a multi-institutional retrospective study in Japan.
Okubo, Y et al.
BMC Cancer 15, 269 (2015). https://doi.org/10.1186/s12885-015-1308-8 - “Gangliocytic paraganglioma is a rare neoplasm that usually occurs in the second portion of the duodenum. It is currently classified as a benign neoplasm, but there are several reports of lymph node and distant metastasis, and there is no validated predictive factor for metastasis. Furthermore, diagnosis with biopsy specimens is sometimes difficult. Careful and complete evaluation with multidepartmental cooperation should be undertaken to accurately diagnose the neoplasm. It is important to remember the possibility of lymph node and distant metastasis.”
Duodenal Gangliocytic Paraganglioma With Lymph Node Metastasis
Hyung Kyu Park, MD; Hye Seung Han, MD, PhD
Arch Pathol Lab Med (2016) 140 (1): 94–98. - Merkel cell carcinoma (MCC) is a rare but highly aggressive skin cancer with neuroendocrine features. MCC pathogenesis is associated with either the presence of Merkel cell polyomavirus or chronic exposure to ultraviolet light (UV), which can cause a characteristic pattern of multiple DNA mutations. Notably, in the Northern hemisphere, the majority of MCC cases are of viral aetiology; by contrast, in areas with high UV exposure, UV-mediated carcinogenesis is predominant. The two aetiologies share similar clinical, histopathological and prognostic characteristics. MCC presents with a solitary cutaneous or subcutaneous nodule, most frequently in sun-exposed areas. In fact, UV exposure is probably involved in both viral-mediated and non-viral-mediated carcinogenesis, by contributing to immunosuppression or DNA damage, respectively.
Merkel cell carcinoma.
Becker, J., Stang, A., DeCaprio, J. et al.
Nat Rev Dis Primers 3, 17077 (2017). https://doi.org/10.1038/nrdp.2017.77
- “Diagnosis is a challenge owing to nonspecific clinical manifestation, rare occurrence, and low index of clinical suspicion. Yet, various small bowel neoplasms have characteristic imaging features at CT and MRI when optimal distention of the small bowel is achieved, correlating well with features seen in gross specimens. Understanding the imaging features of small bowel neoplasms is important to improve the radiologist’s ability to diagnose and characterize small bowel neoplasms. Most small bowel tumors are clinically silent for long periods, and nearly half of the benign tumors are found incidentally during surgery or at cross-sectional imaging performed for other reasons.”
Small Bowel Neoplasms: A Pictorial Review
Jasti R, Carucci LR
RadioGraphics 2020;40:1020-1038 - * Small bowel neoplasms are rare, accounting for 0.5% of all cancers and approximately 3% of all gastrointestinal tumors in the United States, and their incidence is rising—in particular, there is a rising incidence of small bowel carcinoid tumor. CT enterography and MR enterography are optimal imaging studies for assessing for small bowel tumors.
* Adenoma and gastrointestinal stromal tumor (GIST) are the most common benign small bowel tumors and the only two with malignant predisposition.
* GIST may be indistinguishable from other mesenchymal tumors (eg, leiomyoma) at imaging. All GISTs are now con- sidered potentially malignant; therefore, surgical resection should be considered regardless of size.
* The most frequent site of small bowel involvement with lym- phoma is the ileum owing to the presence of abundant lymphoid tissue.
Small Bowel Neoplasms: A Pictorial Review
Jasti R, Carucci LR
RadioGraphics 2020;40:1020-1038 - "Peutz-Jeghers syndrome is a rare autosomal dominant inherited condition, although sporadic cases have been reported. It is less common than familial ad- enomatous polyposis and is characterized by multiple hamartomatous small bowel polyps, which are composed of smooth muscle and covered by normal mucosa. Peutz-Jeghers polyps are most often found in the jejunum followed by the ileum and duodenum.The condition is also characterized by mucocutaneous perioral and genital melanin pigmentation and increased risk of intestinal adenocarcinoma and nongastroin- testinal tumors.”
Small Bowel Neoplasms: A Pictorial Review
Jasti R, Carucci LR
RadioGraphics 2020;40:1020-1038 - "The mean age of diagnosis is 65 years. Small bowel neoplasms demonstrate a higher prevalence in black patients than in white patients . Metastatic lesions of the small bowel from tumors such as melanoma, lung cancer, and breast cancer are more common than primary small bowel malignancy. Among all symptomatic small bowel tumors, malignant lesions are more prevalent than benign lesions. Malignant lesions have a poor prognosis and usually manifest late with subocclusive crisis when at least two-thirds of the bowel lumen is occluded. This is due to the tolerance of the small bowel to obstructive phenomena.”
Small Bowel Neoplasms: A Pictorial Review
Jasti R, Carucci LR
RadioGraphics 2020;40:1020-1038 - “More common risk factors for malignant small bowel tumors include chronic inflammation; inherited conditions such as familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer (HNPCC), and Peutz-Jeghers syndrome; and infections such as human immunodeficiency virus (HIV). Small bowel malignant lesions metastasize frequently owing to the rich portal drainage. Curative surgical resection is the goal of treatment of most small bowel tumors with the exception of early localized lymphoma, for which other nonsurgical treatments have become more refined. Radiation therapy and chemotherapy are usually retained for more advanced stage III or IV disease.”
Small Bowel Neoplasms: A Pictorial Review
Jasti R, Carucci LR
RadioGraphics 2020;40:1020-1038 - "Small bowel adenocarcinoma represents 25%– 40% of primary malignant small bowel tumors. It arises from the glandular epithelium. Predisposing conditions include polyposis syn- dromes, celiac disease, and Crohn disease. The median age of onset is 50–70 years. Primary adenocarcinoma most commonly occurs in the proximal jejunum or distal duodenum. Patients can present with vague symptoms including abdominal pain, nausea, vomiting, weight loss, gastrointestinal bleeding, anemia, and jaundice.”
Small Bowel Neoplasms: A Pictorial Review
Jasti R, Carucci LR
RadioGraphics 2020;40:1020-1038
- “Schwannomas are benign nerve sheath tumors with significant Schwann cell differentiation. They similarly affect both genders and are atypically discovered in patients in their 3th and 5th decades of life. Schwannomas most commonly involve peripheral, motor, sympathetic, or cranial nerves of the head and neck region and upper and lower extremities. Schwannomas have been found at almost every location of the body including in extremities, head, neck, retroperitoneum, mediastinum, pelvis, and rectum. Visceral locations, however, are very rare and preoperative diagnosis is challenging, as schwannomas are often confused with other neoplasms. We review the imaging findings of abdominal schwannomas focusing on pancreatic, gastrointestinal, and retroperitoneal/adrenal schwannomas.”
Abdominal schwannomas: review of imaging findings and pathology.
Lee, N.J., Hruban, R.H. & Fishman, E.K.
Abdom Radiol 42, 1864–1870 (2017). https://doi.org/10.1007/s00261-017-1088-5 - “The most common locations of cellular schwannomas are the paravertebral areas in pelvis, retroperitoneum, and mediastinum. On imaging, the more vascular Antoni A areas are usually enhancing solid components, whereas Antoni B areas are frequently nonenhancing cystic or multiseptated components. Immunohistochemical labeling is a usually required for accurate diagnosis. S-100 protein positivity is an important marker in the diagnosis of schwannoma, as the neoplastic cells strongly label with antibodies to S-100.”
Abdominal schwannomas: review of imaging findings and pathology.
Lee, N.J., Hruban, R.H. & Fishman, E.K.
Abdom Radiol 42, 1864–1870 (2017). https://doi.org/10.1007/s00261-017-1088-5 - “On computed tomography (CT) or magnetic resonance imaging (MRI), schwannomas in various anatomic locations are typically a well-demarcated round or oval masses. Calcification and cystic changes may be seen in larger tumors. After contrast enhancement, homogeneous to heterogeneous contrast enhancement may be seen due to variable degree of internal cystic and hemorrhagic changes. Most schwannomas appear as inhomogeneous low-density masses on CT scan images, isointense with muscle on T1-weighted images, and high intensity on T2-weighted images on MRI.”
Abdominal schwannomas: review of imaging findings and pathology.
Lee, N.J., Hruban, R.H. & Fishman, E.K.
Abdom Radiol 42, 1864–1870 (2017). https://doi.org/10.1007/s00261-017-1088-5 - “Schwannomas rarely arise in the gastrointestinal tract. When they do, they are most often seen in the stomach followed by in small intestine and in colon or the rectum. In addition to the typical histological features of schwannomas, schwannomas of the gastrointestinal tract often have a peripheral cuff of lymphoid cells. Additionally, distinct Antoni A (Verocay bodies) and B areas are usually not present. Schwannomas of the gastrointestinal tract are usually submucosal and richly vascular. The lesions typically protrude into the lumen of the bowel and can be associated with small mucosal erosions, which can be appreciated at endoscopic examination. Because they are submucosal, superficial biopsies may be negative. Most schwannomas of the gastrointestinal tract grow contralateral to the mesenteric attachment. They are usually clinically indolent but can erode the overlying mucosa, causing complications such as bleeding or bowel obstruction.”
Abdominal schwannomas: review of imaging findings and pathology.
Lee, N.J., Hruban, R.H. & Fishman, E.K.
Abdom Radiol 42, 1864–1870 (2017). https://doi.org/10.1007/s00261-017-1088-5 - "Gastrointestinal schwannomas are similar to gastrointestinal stromal tumors (GISTs) on CT or MRI. However, it has been suggested that compared to GISTs, schwannomas tend to be more homogeneously enhancing, more often exophytic or mixed (both endoluminal and exophytic), and slower growing. Homogeneous attenuation may be due to small tumor size and lack of hemorrhage, necrotic, or cystic degeneration. Immunohistochemical labeling is often necessary to confirm the diagnosis. Virtually all GISTs express c-Kit and DOG1, whereas schwannomas are negative for c-Kit and DOG1, and strongly express S100.”
Abdominal schwannomas: review of imaging findings and pathology.
Lee, N.J., Hruban, R.H. & Fishman, E.K.
Abdom Radiol 42, 1864–1870 (2017). https://doi.org/10.1007/s00261-017-1088-5 - "Abdominal Schwannoma is rare and preoperative diagnosis is challenging because of the lack of definitive non-histological diagnostic modalities, as imaging findings are not specific even with developed advanced imaging techniques. Surgical excision is required for treatment and to provide a definitive diagnosis made by histological and immunohistochemical evaluations. Understanding the image findings of abdominal schwannomas will help with considering schwannoma in differential diagnosis appropriately to guide treatment plan and to avoid an unnecessary radical resection.”
Abdominal schwannomas: review of imaging findings and pathology.
Lee, N.J., Hruban, R.H. & Fishman, E.K.
Abdom Radiol 42, 1864–1870 (2017). https://doi.org/10.1007/s00261-017-1088-5
- “B cell lymphoma, especially diffuse large B-cell lymphoma (DLBL), is the most common type of primary gastrointestinal lymphoma, of which primary non-Hodgkin lymphoma (NHL) of gastrointestinal tract accounts for 10–15% of NHLs; the most commonly involved site of DLBL is the ileum of the small bowel. T-cell lymphoma, which occurs much less frequently than B-cell lymphoma, tends to develop in the proximal portion of the small bowel, such as the jejunum or proximal ileum.”
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Kim SW et al.
Abdominal Radiology (2019) 44:2337–2345 - “Perforation is observed in 16–33% of patients with T-cell lymphoma at the time of clinical presentation, and this is attributed to transmural involvement and necrosis. Additionally, T-cell lymphoma is more likely to be multifocal disease than is B-cell lymphoma. In patients with celiac disease, there is an increased incidence of T-cell lymphoma in the small bowel, especially jejunum.”
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Kim SW et al.
Abdominal Radiology (2019) 44:2337–2345 - Some nonneoplastic diseases that occur in the proximal portion of the small bowel occasionally appear as focal wall thickening and may require differentiation from tumorous conditions. Eosinophilic gastroenteritis, characterized by eosinophilic infiltration of the stomach and proximal small bowel, appears as nodular and irregular fold thickening; therefore, it can mimic the appearance of lymphoma or small bowel adenocarcinoma. In addition, giardia- sis and Whipple’s disease present as thickened folds in the distal duodenum and proximal jejunum. Although rare, localized lymphangiectasia of the jejunum resulting from lymphatic blockage of a limited bowel segment may mimic the appearance of lymphoma on CT, as low-attenuating wall thickening of the small bowel
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Kim SW et al.
Abdominal Radiology (2019) 44:2337–2345 
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Kim SW et al.
Abdominal Radiology (2019) 44:2337–2345- “Melanoma accounts for about one-third of all metastases involving the gastrointestinal tract. In a study of 32 patients with small bowel metastases from melanoma, a polypoid pattern with equal distribution between the jejunum and ileum, was found in 20 patients (63%); in addition, approximately 19% of patients showed polyposis (more than 10 masses). The average lag time from the initial diagnosis of melanoma to the detection of small bowel metastases was reported to be 3.2 years.”
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Kim SW et al.
Abdominal Radiology (2019) 44:2337–2345 - “Neuroendocrine tumors occur most commonly in the small bowel, especially the distal ileum; 40% of them are found within 60 cm of the ileocecal valve. Arterial phase CT scanning is useful for the detection of small bowel neuroendocrine tumors, because the tumors usually present with small hyperenhancing masses (30% of these are multiple at diagnosis). Neuroendocrine tumor cells tend to show infiltrative growth through the small bowel wall into the adjacent mesentery, causing mes- enteric fibrosis with the encasement of mesenteric vessels that subsequently results in bowel ischemia. If the primary tumor is larger than 2 cm, nodal metastasis and liver metastasis occur in more than 80% and 40% of tumors, respectively.”
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Kim SW et al.
Abdominal Radiology (2019) 44:2337–2345 - Hypervascular masses in the small bowel: Differential Dx
- hemangiomas
- small GISTs
- neuroendocrine tumors
- malignant gastrointestinal neuroectodermal tumors (GNETs)
- metastases of hypervascular primary cancer - Purpose To evaluate the feasibility of using computed tomography texture analysis (CTTA) parameters for predicting malignant risk grade and mitosis index of gastrointestinal stromal tumors (GISTs), compared with visual inspection.
Conclusion Using TexRAD, MPP and kurtosis are feasible in predicting risk grade and mitosis index of GISTs. CTTA demonstrated meaningful accuracy in preoperative risk stratification of GISTs.
Feasibility of using computed tomography texture analysis parameters as imaging biomarkers for predicting risk grade of gastrointestinal stromal tumors: comparison with visual inspection
Choi IY et al.
Abdominal Radiology (2019) 44:2346–2356 - “In the NCCN guideline, if the size of the tumor is more than 10 cm or the mitosis count is more than 5 in high- power fields (HPFs), the gastric GIST is classified as a high risk. For tumors in the small and large intestines, if the tumor size exceeds 5 cm, or the mitosis count is more than 5 in 50 HPFs, the tumor is classified as a high risk.”
Feasibility of using computed tomography texture analysis parameters as imaging biomarkers for predicting risk grade of gastrointestinal stromal tumors: comparison with visual inspection
Choi IY et al.
Abdominal Radiology (2019) 44:2346–2356 - “Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. About 10–30% of GISTs are clinically malignant, but all GISTs are considered to have some degree of malignant potential. The malignancy risk of GISTs is deter- mined based on the mitotic index, tumor size, and site of the lesion according to National Comprehensive Cancer Network (NCCN) guidelines.”
Feasibility of using computed tomography texture analysis parameters as imaging biomarkers for predicting risk grade of gastrointestinal stromal tumors: comparison with visual inspection
Choi IY et al.
Abdominal Radiology (2019) 44:2346–2356 - “In conclusions, CTTA parameters, such as MPP and kurtosis can be useful in predict the risk grade and mitosis index of GISTs. In our study, texture analysis parameters demonstrated meaningful accuracy in preoperative diagnosis of tumor risk stratification and can be used as imaging biomarkers for determination of tumor grade.”
Feasibility of using computed tomography texture analysis parameters as imaging biomarkers for predicting risk grade of gastrointestinal stromal tumors: comparison with visual inspection
Choi IY et al.
Abdominal Radiology (2019) 44:2346–2356
- “Except for adenoma, adenocarcinoma, and neuroendocrine tumor that arise from the epithelial layer, most tumors originating from the small bowel develop in the submucosal layer, including lymphoma, lipoma, hemangioma, inflammatory fibroid polyp, and malignant gastrointestinal neuroectodermal tumor. In addition, gastrointestinal stromal tumor originates from the muscularis propria. Metastasis can involve the various layers of the small bowel according to spreading mechanism.”
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Sang Won Kim et al.
Abdominal Radiology https://doi.org/10.1007/s00261-019-01978-5 - Small Bowel Adenocarcinoma: Increased Risk Factors
- familial adenomatous polyposis
- Lynch syndrome
- Peutz-Jeghers syndrome
- Crohn’s disease
- celiac disease
- alcohol consumption and
- smoking - “T-cell lymphoma, which occurs much less frequently than B-cell lymphoma, tends to develop in the proximal portion of the small bowel, such as the jejunum or proximal ileum. Perforation is observed in 16–33% of patients with T-cell lymphoma at the time of clinical presentation, and this is attributed to transmural involvement and necrosis. Additionally, T-cell lymphoma is more likely to be multifocal disease than is B-cell lymphoma.”
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Sang Won Kim et al.
Abdominal Radiology https://doi.org/10.1007/s00261-019-01978-5 - “B cell lymphoma, especially diffuse large B-cell lymphoma (DLBL), is the most common type of primary gas- trointestinal lymphoma, of which primary non-Hodgkin lymphoma (NHL) of gastrointestinal tract accounts for 10–15% of NHLs; the most commonly involved site of DLBL is the ileum of the small bowel.”
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Sang Won Kim et al.
Abdominal Radiology https://doi.org/10.1007/s00261-019-01978-5 
Tumors of the jejunum and ileum: a pattern‐based imaging approach on CT
Sang Won Kim et al.
Abdominal Radiology https://doi.org/10.1007/s00261-019-01978-5
- “Although the small intestine accounts for over 90% of the surface area of the alimentary tract, tumors of the small intestine represent less than 5% of all gastrointestinal tract neoplasms. Common small bowel tumors typically are well evaluated with cross-sectional imaging modalities such as CT and MR, but accurate identification and differentiation can be challenging. Differentiating normal bowel from abnormal tumor depends on imaging modality and the particular technique. While endoscopic evaluation is typically more sensitive for the detection of intraluminal tumors that can be reached, CT and MR, as well as select nuclear medicine studies, remain superior for evaluating extraluminal neoplasms. Understanding the imaging characteristics of typical benign and malignant small bowel tumors is critical, because of overlapping features and associated secondary complications.”
Multimodality imaging of small bowel neoplasms.
Williams EA1, Bowman AW2
Abdom Radiol (NY). 2019 (in press)
- “Neurofibromatosis type 1 (NF1) is one of the most common genetic disorders. Gastrointestinal manifestations of NF-1 are seldom thought of in routine clinical practice and might thus be significantly under-recognized. Their heterogeneous spectrum ranges from localized microscopic proliferative lesions to grossly recognizable mass-forming neurofibromas, neuroendocrine and gastrointestinal stromal tumours (GIST).”
Spectrum of gastrointestinal lesions of neurofibromatosis type 1: a pictorial review
Garrouche N et al.
Insights into Imaging
https://doi.org/10.1007/s13244-018-0648-8 - “Neurofibromatosis type 1 (NF1) or Recklinghausen disease is a tumour syndrome caused by alterations in the NF-1 gene . It belongs to a group of disorders referred to as phakomatoses or neurocutaneous syndromes, including neurofibromatosis (type 1 and type2 ), tuberous sclerosis (Bourneville-Pringle disease), Von Hippel-Lindau (VHL) disease, Sturge-Weber syndrome (SWS) and many other neurocutaneous diseases (ataxia telangiectasia, incontinentia pigmenti, etc.”
Spectrum of gastrointestinal lesions of neurofibromatosis type 1: a pictorial review
Garrouche N et al.
Insights into Imaging
https://doi.org/10.1007/s13244-018-0648-8 - “Gastrointestinal tract neoplasms in NF-1 patients are more frequent than in the general population and occur in three main forms: hyperplasia of the submucosal and myenteric nerve plexuses and mucosal ganglioneuromatosis that leads to disordered gut motility; gastrointestinal stromal tumours (GIST) with varying degrees of neural or smooth muscle differentiation; distinctive glandular somatostatine-rich carcinoid in the periampullary region of the duodenum, which contains psammoma bodies and may be associated with pheochromocytoma. “
Spectrum of gastrointestinal lesions of neurofibromatosis type 1: a pictorial review
Garrouche N et al.
Insights into Imaging
https://doi.org/10.1007/s13244-018-0648-8 - “Bakker and al examined 61 reported cases of non- carcinoid gastrointestinal (GI) neoplasms in patients with NF-1. Neoplasms were located most often in the small intestine (72%). Neurofibromas (52%) were the most frequently diagnosed benign neoplasms followed by leiomyomas (13%), ganglioneurofibromas (9.8%) and gastrointestinal stomal tumour (GIST) (6.5%). Malignant tumour adenocarcinoma accounted for 23% in this review.”
Spectrum of gastrointestinal lesions of neurofibromatosis type 1: a pictorial review
Garrouche N et al.
Insights into Imaging
https://doi.org/10.1007/s13244-018-0648-8 - Gastrointestinal stromal tumour (GIST) is a mesenchymal tumour that represents the most common gastrointestinal manifestation of NF-1. It is reported in 5–25% of NF1 patients and accounts for 1.5% of all GISTs. GISTs associated with NF1 syndrome seem to have a distinct phenotype compared with sporadic GISTs: they occur in younger patients (mean age, 49 years versus 56 in sporadic GISTs), are multiple in 60% or develop in multiples sites, are smaller in size with low mitotic activity, follow a benign clinical course and occur mostly in the duodenum or small intestine. They are usually clinically asymptomatic and detected as incidental findings.
Spectrum of gastrointestinal lesions of neurofibromatosis type 1: a pictorial review
Garrouche N et al.
Insights into Imaging
https://doi.org/10.1007/s13244-018-0648-8 - Neurofibromatosis and the GI Tract
- Neurofibromatosis type (NF-1) is one of the most common single gene disorders.
- Every organ system can be involved and intra-abdominal manifestations are underestimated.
- The NF1 abdominal manifestations comprehend five categories of tumours.
- Neurogenic tumours including with neurofibromas are the most common type.
- Early diagnosis of abdominal manifestations of NF-1 based on imaging patterns is necessary for appropriate treatment to avoid
- serious organic complications related to tumour mass.
- “Small bowel adenocarcinomas are rare malignant tumors that account for less than 2% of gastrointestinal tumors. Among malignant tumors of the small bowel (SB), adenocarcinoma is the most frequent etiology in France followed by endocrine tumors, lymphomas or stromal tumors . Recent trends show that SB neuroendocrine tumors outnumber SB adenocarcinoma in the US .Epidemiological data estimate the annual incidence of small bowel adenocarcinoma at 2.2–5.7/million in developed countries. In the French Côte d'Or study, the incidence of small bowel adenocarcinoma was 0.18/100,000 men and 0.1/100,000 women during the period 1996–2001, and which incidence increased with age. However, and as is the case for colon cancer, the incidence of small bowel adenocarcinoma is increasing in the population. Moreover, duodenal tumors are more frequent than tumors in other segments (jejunum and ileum).”
Small bowel adenocarcinoma: French intergroup clinical practice guidelines for diagnosis, treatments and follow-up Christophe Locher et al. Digestive and Liver Disease (in press) - “Indeed, duodenal tumors account for 50% of small bowel adenocarcinomas while tumors of the jejunum and ileum represent 30% and 20%, respectively . The stage at diagnosis is usually advanced; in the series of Talamonti et al., 38% of the patients had synchronous metastases and 38% had lymph-node invasion . In the MD Anderson study, the same distribution by stage was found (35% of metastatic patients and 39% with lymph-node invasion).”
Small bowel adenocarcinoma: French intergroup clinical practice guidelines for diagnosis, treatments and follow-up Christophe Locher et al. Digestive and Liver Disease (in press) - “In celiac disease, the risk of developing small bowel adenocarcinoma is low (8 cases per 11,000 patients for the Swedish registry). Duodenal biopsies during the initial endoscopy and an anti-transglutaminase (IgA) or anti-transglutaminase (IgG) and anti-endomysium (IgG) antibody assay in cases of IgA deficiency are recommended.”
Small bowel adenocarcinoma: French intergroup clinical practice guidelines for diagnosis, treatments and follow-up Christophe Locher et al. Digestive and Liver Disease (in press) - “The relative risk of developing small bowel adenocarcinoma in Crohn’s disease is about 20. In Crohn’s disease, the preferred location is the ileum and the age at onset is younger (4th decade) . If there is a family history of Crohn’s disease or if there are clinical symptoms, a morphological examination of the small bowel and a proctologic examination are recommended.”
Small bowel adenocarcinoma: French intergroup clinical practice guidelines for diagnosis, treatments and follow-up Christophe Locher et al. Digestive and Liver Disease (in press)
- “Small bowel cancers are very rare despite the length and large mucosal surface of the small bowel and account for 3% to 6% of all gastroin- testinal (GI) tract malignancies. Adenocarcinoma, neuroendocrine neoplasms, lymphoma, and GI stromal tumors (GISTs) are the most prevalent primary small bowel cancers, with adenocarcinoma and neuroendocrine neoplasms accounting for nearly two-thirds of small bowel cancers.”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press) - “Capsule endoscopy is a safe and minimally invasive modality for visualizing the entire small bowel. It is typically well tolerated by patients. The limitations of the procedure include diagnostic procedure (no therapeutic ability), potential of missing a lesion, decreased visualization if fluid or bubbles are retained in the lumen, false- positive findings, and capsule retention if stricture or significant inflammation present.”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press) - “There are mixed results for capsule endoscopy in the detection of small bowel tumors. In small retrospective and prospective single-center studies, CT enterography was shown to be superior to capsule endoscopy in the detection of small bowel tumors.”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press) - “Several hereditary conditions, including familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer (also known as Lynch syndrome), Peutz- Jeghers syndrome, MUTYH-associated polyposis, and cystic fibrosis, are well known to be associated with increased risk for small bowel adenocarcinoma. .”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press) - “The most typical appearance of small bowel adenocarcinoma is an annular, constricting mass (apple-core lesion) that causes luminal narrowing that is often associated with upstream bowel dilatation. Even a small encircling adenocarcinoma can cause small bowel obstruction due to prominent intratumoral desmoplasia, and a small obstructing cancer should not
be neglected.”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press) - “A variety of conditions increase the risk of small bowel GISTs. Familial GIST is autosomal dominant and often leads to the development of a single or multiple GISTs in middle age. Additionally, about 5% of patients with neurofibromatosis type 1 (NF-1) will present with a small bowel GIST; GISTs can be seen in young females as part of the Carney triad (gastric or small bowel GIST, pulmonary chondroma, and extra-adrenal pheochromocytoma) or in males or females as part of the Carney-Stratakis syndrome (GIST and paraganglioma).”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press) - “Neuro- endocrine neoplasms typically occur in distal/terminal ileum, with the small bowel primary presenting as a small enhancing polyp or more
characteristically as a plaquelike mass, often with serosal retraction. Tumor can be singular or multifocal along a bowel segment. Nodal metastases typically cluster around mesenteric vessels (with potential to narrow or occlude them), with advanced mesenteric metastases presenting with a characteristic pattern of rounded soft tissue, punctate calcification, and radiating strands of desmoplasia.”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press) - “Crohn disease can mimic small bowel tumors; patients with long-standing Crohn disease are at increased risk for these tumors, particularly lymphoma and adenocarcinoma, which can be discovered incidentally. Radiological diagnosis of small bowel tumors developing in Crohn disease is very difficult because the imaging findings are similar to the findings of long- standing Crohn disease, and biopsy should be used when required to distinguish between them.”
Imaging and Screening of Cancer of the Small Bowel Jin Sil Kim et al. Radiol Clin N Am (2017) (in press)
- Treatment
• Surgical resection is mainstay therapy for isolated small tumors without evidence of metastatic disease.
• Laparoscopic resection may be attempted for small tumors with open procedures reserved for larger tumors.
• Imatinib mesylate, a tyrosine kinase inhibitor, is first line therapy for patients who are poor surgical candidates, or show evidence of recurrence or metastatic disease.
• Can also be used as neoadjuvant therapy to preoperatively shrink large tumors - Imaging Surveillance
• Surveillance after surgery includes CT scanning with contrast every 3 to 6 months.
• Low grade small tumor may have scans every 6 to 12 months.
• Patients receiving imatinib mesylate therapy may have scans every 3 months.
• Dual phase imaging is recommended as arterial phase may detect new enhancing components in stable disease that may wash out during venous phase and be overlooked.
- Small Bowel Carcinoid Tumors: Facts
• Second most common small bowel malignancy.
• Rarely presents with carcinoid syndrome (watery diarrhea, flushing and endocardial fibrosis) when disease spreads to the liver
• Appendix most common site followed by ileum
• Avidly enhancing polypoid mass.
• Primary tumor usually small.
• Tumor spread with calcified mesenteric mass with desmoplastic response and tethering of adjacent small bowel loops.
• Liver metastasis usually hypervascular
- “For both GIST and NET, the mean attenuation values of the tumors were significantly higher than those of adenocarcinoma and lymphoma in both the arterial and enteric phases (all p-values < 0.05). The mean attenuation value of GIST was significantly higher than that of metastases in both the arterial (p = 0.041) and enteric phases (p = 0.000199). The mean attenuation value of NET was significantly higher than that of metastases in the enteric phase (p = 0.000199).”
Small bowel neoplasms: enhancement patterns and differentiation using post-contrast multiphasic multidetector CT Shinya, T., Inai, R., Tanaka, T. et al. Abdom Radiol (2017) 42: 794. doi:10.1007/s00261-016-0945-y - “The use of multiphasic threshold levels led to an improvement in diagnostic accuracy; GIST could be discriminated from adenocarcinoma with an accuracy of 82.76%, GIST could be discriminated from lymphoma with an accuracy of 87.50%, and NET from adenocarcinoma with an accuracy of 92.00%.”
Small bowel neoplasms: enhancement patterns and differentiation using post-contrast multiphasic multidetector CT Shinya, T., Inai, R., Tanaka, T. et al. Abdom Radiol (2017) 42: 794. doi:10.1007/s00261-016-0945-y - “In conclusion, the mean CT attenuation values could potentially be useful to discriminate between the small bowel neoplasms with acceptable diagnostic capacities, using individual monophasic and multiphasic threshold levels on post-contrast multiphasic MDCT, particularly in the arterial phase, for the four primary small bowel neoplasms in this study. The results of our study suggest that there may be a consistent relationship between the enhancement pattern on post-contrast multiphasic MDCT and the histologic findings and that the multiphasic dynamic enhancement data could be a robust tool for the discrimination of small bowel neoplasms.”
Small bowel neoplasms: enhancement patterns and differentiation using post-contrast multiphasic multidetector CT Shinya, T., Inai, R., Tanaka, T. et al. Abdom Radiol (2017) 42: 794. doi:10.1007/s00261-016-0945-y
- “The duodenum can be involved in several major polyposis syndromes, including familial adenomatous polyposis (FAP), Peutz Jeghers syndrome, Cronkite Canada syndrome, and juvenile polyposis. Duodenal polyps are commonly found in patients with Cronkite Canada syndrome, which shows similarities to juvenile polyposis, but polyps are usually small and more diffuse. Ectodermal changes, such as alopecia and nail dystrophy; and inflammatory infiltrate in lamina propria are associated with Cronkite Canada syndrome. Polyps associated with Cronkite Canada syndrome are more commonly sessile than pedunculated.”
Imaging Spectrum of Non-neoplastic Duodenal Diseases Sitthipong S et al. Clinical Imaging (in press)
- “Small bowel cancer is a rare malignancy that comprises less than 5 % of all gastrointestinal malignancies. The estimated annual incidence is 0.3–2.0 cases per 100,000 persons, with a higher prevalence rates in the black population than the white, and has been recently increasing. It is most frequently diagnosed among people aged 55–64, with the incidence increasing after age 40. The current 5-year survival rate in the USA is 65.5 %; cancer stage at diagnosis has a strong influence on the length of survival.”
Small bowel adenocarcinoma of the jejunum: a case report and literature review Li J et al. World Journal of Surgical Oncology201614:177 - “Small bowel cancer has four common histological types: adenocarcinoma (30–40 %), carcinoid tumour (35–42 %), lymphoma (15–20 %), and sarcoma (10–15 %). Adenocarcinoma of the small bowel (SBA) is most commonly located in the duodenum (57 %), while 29 % of cases are located in the jejunum and 10 % in the ileum. Clinical presentation of SBA is nonspecific abdominal discomfort, such as abdominal pain, nausea, vomiting, gastrointestinal bleeding and intestinal obstruction, which leads to an average delay of 6–10 months in diagnosis.”
Small bowel adenocarcinoma of the jejunum: a case report and literature review Li J et al. World Journal of Surgical Oncology201614:177 - “Whereas the small bowel represents 75 % of the length of the digestive tract and 90 % of the absorptive mucosal surface area, tumour of the small bowel is rarer than other gastrointestinal malignancies. The possible explanations include the high levels of IgA and the more rapid transit in the small bowel compared to the large bowel. Little bacteria and more sensitivity to stress in the small bowel also contribute to the low tumour incidence.”
Small bowel adenocarcinoma of the jejunum: a case report and literature review Li J et al. World Journal of Surgical Oncology201614:177 - “Surgical resection with clear margins and regional lymph node resection remains the treatment of choice in localized SBA; indeed, it is often required even in metastatic SBA due to the high probability of obstruction or severe haemorrhage. To date, there has been no standard chemotherapy regimen against SBA. Several studies have explored the role of palliative chemotherapy in advanced SBA. Hong et al.have shown in stage IV patients who received palliative chemotherapy that overall survival (OS) increased significantly compared to those who did not receive chemotherapy (8 vs. 3 months, p = 0.025). Ecker et al. have shown that median OS was superior for patients with resected stage III SBA who were receiving chemotherapy versus those who were not (42.4 vs 26.1 months, p < 0.001).”
Small bowel adenocarcinoma of the jejunum: a case report and literature review Li J et al. World Journal of Surgical Oncology201614:177 - Small Bowel Cancer Facts
- Common Cancer Numbers
- Small Bowel Cancer: By The Numbers
- “Metastases from colon cancer, ovarian carcinoma, breast cancer, lung cancer, carcinoid, and melanoma can spread to mesenteric lymph nodes. However, the degree of nodal enlargement seen in mesenteric metastatic disease is less pronounced than that seen in mesenteric lymphoma, and the distribution of in- volved nodes is comparatively more localized in metastatic disease”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheila Sheth, MD ● Karen M. Horton, MD ● Melissa R. Garland, MS ● Elliot K. Fishman
RadioGraphics 2003; 23:457– 473 - “Tumors originating in the abdomen or elsewhere in the body can disseminate to the mesentery in four major ways: (a) direct spread along the mesenteric vessels and surrounding fat, (b) extension via the mesenteric lymphatics, (c) embolic hematogenous spread, and (d) intra- peritoneal seeding. Although convenient, this classification is somewhat arbitrary, since many neoplasms spread by more than one route.”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheila Sheth, MD ● Karen M. Horton, MD ● Melissa R. Garland, MS ● Elliot K. Fishman
RadioGraphics 2003; 23:457– 473 - Mesenteric Masses: Pathways
(a) direct extension, commonly seen with carcinoid tumor of the small intestine as well as intraabdominal cancers such as pancreatic and colon cancer;
(b) lymphatic dissemination of lymphoma and some epithelial malignancies;
(c) hematogenic spread resulting in embolic metastases to the small intestinal wall, usually seen in melanoma and breast cancer;
(d) seeding through the peritoneum from ovarian and gastrointestinal malignancies as well as some lymphomas. - Primary Mesenteric Neoplasms
- Desmoid tumor
- Carcinoid Tumor
- Sclerosing Mesenteritis
- Lymphoma
- Metastases - Round Well Defined Mesenteric Masses: Differential Diagnosis
- Non-Hodgkin lymphoma
- Metastases
- M avium–intracellulare
- tuberculosis
- Whipple disease
- Mesenteric cyst
- Mesenteric lipoma
- Castleman disease - Ill Defined Mesenteric Masses: Differential Diagnosis
- Small bowel carcinoid
- Mesenteric desmoid
- Tumor infiltration from pancreatic, gastric, or colon cancer
- Lymphoma
- Sclerosing mesenteritis - Stellate Mesenteric Masses: Differential Diagnosis
- Sclerosing mesenteritis
- Carcinomatosis; pancreatic, gastrointestinal, ovarian, or breast or colon cancer
- Peritoneal lymphomatosis
- Malignant peritoneal mesothelioma
- Peritoneal tuberculosis
- Systemic amyloidosis
- Vascular thrombosis
- "Duodenal carcinoid tumors commonly appear as an enhancing mass in either the arterial or venous phases. If a primary tumor is not seen in the duodenum, adjacent enhancing lymphadenopathy can be a clue to the presence of a duodenal carcinoid tumor."
Duodenal neuroendocrine tumors: retrospective evaluation of CT imaging features and pattern of metastatic disease on dual-phase MDCT with pathologic correlation.
Tsai SD, Kawamoto S, Wolfgang CL, Hruban RH, Fishman EK
Abdom Imaging. 2015 Jun;40(5):1121-30 - "On CT, 19 patients (67.8%) had neuroendocrine tumors manifested as polypoid or intraluminal masses (38 lesions, multiple tumors in 3 patients), 4 patients (14.3%) had tumors manifested as wall thickening or intramural masses, and in 5 patients (17.9%), the primary tumor was not visualized. Lesions not seen at CT were less than 0.8 cm on pathologic diagnosis. The mean size of polypoid tumors on CT was 1.2 cm (range 0.3-3.8 cm); 24 tumors were 1.0 cm or smaller, and 14 tumors were larger than 1.0 cm."
Duodenal neuroendocrine tumors: retrospective evaluation of CT imaging features and pattern of metastatic disease on dual-phase MDCT with pathologic correlation.
Tsai SD, Kawamoto S, Wolfgang CL, Hruban RH, Fishman EK
Abdom Imaging. 2015 Jun;40(5):1121-30 - "Most lesions were hypervascular in the arterial phase (19/23 patients) with an increase in tumor enhancement in the venous phase in 14 patients (60.9%), decrease in enhancement in 7 patients (30.4%), and no change in enhancement in 2 patients (8.7%). Thirteen patients (46.4%) had metastatic disease from carcinoid tumor, most commonly regional enhancing lymphadenopathy."
Duodenal neuroendocrine tumors: retrospective evaluation of CT imaging features and pattern of metastatic disease on dual-phase MDCT with pathologic correlation.
Tsai SD, Kawamoto S, Wolfgang CL, Hruban RH, Fishman EK
Abdom Imaging. 2015 Jun;40(5):1121-30 - "Gastrointestinal (GI) neuroendocrine tumors are submucosal masses with differentiation in the direction of neuroendocrine cells of the GI tract and comprise 1.2-1.5% of all GI tract neoplasms . Neuroendocrine cells are located throughout the body with two-thirds of neuroendocrine tumors arising in the GI tract, 25% in the lungs, and the remaining 10% in other sites in the body ."
Duodenal neuroendocrine tumors: retrospective evaluation of CT imaging features and pattern of metastatic disease on dual-phase MDCT with pathologic correlation.
Tsai SD, Kawamoto S, Wolfgang CL, Hruban RH, Fishman EK
Abdom Imaging. 2015 Jun;40(5):1121-30 - "Most duodenal carcinoids are sporadic but may be associated with clinical syndromes such as multiple endocrine neoplasia type 1 (MEN-1) and neurofibromatosis type 1(NF-1) . Two-thirds of duodenal neuroendocrine tumors are gastrinomas and one-third of these are functioning tumors manifesting as Zollinger-Ellison syndrome (ZES). The next most common type (20%) of duodenal neuroendocrine tumors is somatostatinomas."
Duodenal neuroendocrine tumors: retrospective evaluation of CT imaging features and pattern of metastatic disease on dual-phase MDCT with pathologic correlation.
Tsai SD, Kawamoto S, Wolfgang CL, Hruban RH, Fishman EK
Abdom Imaging. 2015 Jun;40(5):1121-30 - "Of the neuroendocrine tumors visualized at CT (either as polypoid intraluminal masses or wall thickening and intramural masses), the tumor was located in the second portion of the duodenum in 14 patients (60.9%), in the duodenal bulb in 4 patients (17.4%), and in the third portion of the duodenum in 2 patients (8.7%). Of the 14 patients whose tumors were located in the second portion of the duodenum, 10 (43.5%) had tumors in the peri-ampullary region; two of these patients had NF-1."
Duodenal neuroendocrine tumors: retrospective evaluation of CT imaging features and pattern of metastatic disease on dual-phase MDCT with pathologic correlation.
Tsai SD, Kawamoto S, Wolfgang CL, Hruban RH, Fishman EK
Abdom Imaging. 2015 Jun;40(5):1121-30
- “The duodenal GISTs were solitary masses with well-defined margins. The average diameter was 7.1 cm. The second portion was the most common site (20/34). Ulceration was a common feature (15/34). Calcification was uncommon (3/34), and mixed growth pattern was more common (26/34). Rim enhancement (24/34) and mixed enhancement pattern (15/34) were common. Arterial blood supply, intratumoral vasculature, and draining veins were all detected and were obvious on the arterial phase. The portal venous trunk and superior mesenteric vein were the main veins into which early arterioportal shunting drained.”
CT Characterization of Duodenal Gastrointestinal Stromal Tumors. Cai PQ et al. AJR Am J Roentgenol. 2015 May;204(5):988-93 - “Primary duodenal GISTs are generally large, well-defined, heterogeneously enhancing, and hypervascular masses with a prominent mixed growth pattern on CT images. Our findings suggest that CT can help depict the origin of the tumoral arteries and draining veins on the arterial phase and may be a key defining diagnostic feature for duodenal GISTs.”
CT Characterization of Duodenal Gastrointestinal Stromal Tumors. Cai PQ et al. AJR Am J Roentgenol. 2015 May;204(5):988-93 - “Almost all GISTs express active KIT receptor tyrosine kinase (CD117) mutants, which are crucial for the diagnosis of GISTs. The constitutive expression of CD117 in GISTs also distinguishes them from other mesenchymal neoplasms, such as leiomyomas, leiomyosarcomas, schwanno-
mas, and neurofibromas.”
CT Characterization of Duodenal Gastrointestinal Stromal Tumors. Cai PQ et al. AJR Am J Roentgenol. 2015 May;204(5):988-93 - “GISTs can arise anywhere in the gastro-
intestinal tract, most commonly in the stom- ach (60–70%) followed by the small bowel (20–25%). GISTs in the duodenum are rare (less than 5%).”
CT Characterization of Duodenal Gastrointestinal Stromal Tumors. Cai PQ et al. AJR Am J Roentgenol. 2015 May;204(5):988-93 - “All of the cases were solitary masses. The average diameter of the masses was 7.1 cm (range, 1.8–13.4 cm). Among the four portions of duodenum, the largest mean diameter of masses (9.8 cm; range, 6.6–13.4 cm) was located in the fourth portion and the smallest (2.3 cm; range, 1.8–2.8 cm) in the first portion.”
CT Characterization of Duodenal Gastrointestinal Stromal Tumors. Cai PQ et al. AJR Am J Roentgenol. 2015 May;204(5):988-93 - “The mean tumor attenuation in the most strongly enhanced portion in arterial, portal venous, and delayed phases was 118 HU (range, 63–180 HU), 106 HU (range, 60–145 HU), and 94 HU (range, 60–125 HU), respectively. Rim enhancement (24/34, which was obvious in the arterial phase) and mixed enhancement patterns (15/34) were common.”
CT Characterization of Duodenal Gastrointestinal Stromal Tumors. Cai PQ et al. AJR Am J Roentgenol. 2015 May;204(5):988-93 - “In conclusion, primary duodenal GISTs are generally large, well-defined, heterogeneously enhancing, and hypervascular masses with a prominent mixed growth pattern on CT images. Our findings suggest that CT can help depict the origin of the tumoral arteries and draining veins in the arterial phase, which may be a key in defining diagnostic features for duodenal GISTs.”
CT Characterization of Duodenal Gastrointestinal Stromal Tumors. Cai PQ et al. AJR Am J Roentgenol. 2015 May;204(5):988-93 - Duodenal GIST Tumors: Differential Dx
- Duodenal adenocarcinoma
- Lymphoma
- Pancreatic head adencarcinoma
- “Many risk factors for primary GI lymphoma have been described, including celiac disease, human immunodeficiency virus infection/acquired immunodeficiency syndrome, ulcerative colitis, Crohn's disease, and immunosuppression following solid organ transplantation. Patients with celiac disease have a 200-fold increased risk of developing intestinal lymphoma, particularly enteropathy-associated T-cell lymphoma, which has an extremely poor prognosis with a median survival time of 4 months.”
Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65. - “The small bowel represents the second most common site of primary GI lymphoma, comprising approximately 24%-26%. Compared with primary GI lymphoma of the stomach, which tends to be of lower grade, small-bowel lymphomas are diagnosed at higher grades.”
Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65. - “Although the ileum is most often affected by B-cell lymphomas presumably based on the relative abundance of lymphatic tissue, the jejunum appears to be more often involved in uncommon but more aggressive T-cell lymphomas. Lymphoma often affects multiple sites of small bowel with a roughly equal likelihood of affecting the same segment or different segments.Over 77% of lymphoma exceeds 5 cm in diameter, and the average length of affected bowel is 12 cm.”
Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65. - “Lymphoma of the small bowel commonly demonstrates an infiltrative pattern causing diffuse bowel wall thickening with or without aneurysmal dilation and less often an “annular napkin-ring lesion” mimicking adenocarcinoma. Other patterns of small-bowel lymphoma include solitary or multiple nodules or large polypoid masses.The differential diagnosis for these findings includes Crohn's disease, adenocarcinoma, carcinoid, GI stromal tumor, or metastatic disease (eg, melanoma).”
Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65. - “The survival rate for primary GI lymphoma is highly variable depending on stage, primary site, and subtype, but is generally good, ranging from 44%-67%.Distinguishing between primary and secondary GI lymphoma is clinically important, however, because primary GI lymphoma carries a better 5-year survival rate than disseminated secondary GI lymphoma and a significantly better survival rate than other common GI malignancies such as adenocarcinoma. Tumors are often amenable to chemotherapy and radiation, and can occasionally undergo surgical debulking or resection due to perforation or other acute complication.”
Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65.
- “Primary tumors arising in the mesentery are relatively rare.On the other hand, the mesentery is a frequent avenue of spread for malignant neoplasms through the peritoneal cavity and between the peritoneal spaces and the retroperitoneum. Patients with mesenteric neoplasms usually present with nonspecific symptoms of abdominal pain, weight loss, a palpable abdominal mass, or diarrhea. CT plays a critical role in achieving an accurate diagnosis of these neoplasms to guide patient management.”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheth S, Horton KM, Garland MR, Fishman EK
RadioGraphics Mar 2003, Vol. 23, No. 2:457–473 - “Desmoid tumors are rare, locally aggressive, nonencapsulated masses resulting from a benign proliferation of fibrous tissue. Abdominal desmoids can occur sporadically and develop anywhere in the abdomen, including the musculature of the abdominal wall, the retroperitoneum, and the pelvis. However, desmoids forming in the mesentery are especially common in patients with familial adenomatous polyposis (Gardner syndrome), occurring in 9%–18% of cases .”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheth S, Horton KM, Garland MR, Fishman EK
RadioGraphics Mar 2003, Vol. 23, No. 2:457–473 - “Sclerosing mesenteritis is a rare inflammatory condition of unknown cause that affects the root of the mesentery. The mesenteric fat is involved with a variable amount of inflammation, fatty necrosis, and fibrosis. When the inflammation predominates (so-called mesenteric panniculitis), patients generally present with acute pain. On CT images, mesenteric panniculitis appears as a focal area of increased attenuation within the mesenteric fat surrounded by a pseudocapsule (Fig 5), an appearance that has been described as “the misty mesentery”. Areas of fibrosis within the inflamed fat appear as linear bands of soft-tissue attenuation .”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheth S, Horton KM, Garland MR, Fishman EK
RadioGraphics Mar 2003, Vol. 23, No. 2:457–473 - “At CT, the most common manifestation of mesenteric carcinoid tumors is that of an enhancing soft-tissue mass with linear bands radiating in the mesenteric fat . Radiologic-pathologic correlation has shown that these radiating strands of soft tissue do not generally represent tumor infiltration along neurovascular bundles but rather result from the intense fibrotic proliferation and desmoplastic reaction in the mesenteric fat and the adjacent mesenteric vessels caused by the release of serotonin and other hormones from the primary tumor .”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheth S, Horton KM, Garland MR, Fishman EK
RadioGraphics Mar 2003, Vol. 23, No. 2:457–473 - “Lymphoma is the most common malignant neoplasm affecting the mesentery . Approximately 30%–50% of patients with non-Hodgkin lymphoma harbor disease in the mesenteric lymph nodes. Markedly mesenteric adenopathy can also be present in chronic lymphocytic leukemia. Patterns of mesenteric lymphoma at CT include multiple, rounded, mildly enhancing, homogeneous masses that often encase the mesenteric vessels and produce the “sandwich sign.”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheth S, Horton KM, Garland MR, Fishman EK
RadioGraphics Mar 2003, Vol. 23, No. 2:457–473 - “Patterns of mesenteric lymphoma at CT include multiple, rounded, mildly enhancing, homogeneous masses that often encase the mesenteric vessels and produce the “sandwich sign” ; a large, lobulated, “cakelike,” heterogeneous mass with low-attenuation areas of necrosis displacing small bowel loops ; or an ill-defined infiltration of the mesenteric fat, particularly after successful chemotherapy. Bulky retroperitoneal adenopathy commonly accompanies the mesenteric disease and should be a clue to the diagnosis .”
Mesenteric Neoplasms: CT Appearances of Primary and Secondary Tumors and Differential Diagnosis
Sheth S, Horton KM, Garland MR, Fishman EK
RadioGraphics Mar 2003, Vol. 23, No. 2:457–473
- “ Retroperitoneal liposarcomas are rare mesenchymal tumors of the retroperitoneum that typically present with advanced disease and often carry a poor prognosis. Because of their rarity and anatomic location, these malignant tumors can cause a diagnostic dilemma and present several therapeutic challenges. They are usually associated with a high rate of recurrence despite grossly complete resection, thus requiring long-term and often indefinite follow-up.”
Retroperitoneal Liposarcoma: A Comprehensive Review.
Vijay A, Ram L.
Am J Clin Oncol. 2013 Oct 16. [Epub ahead of print] - “When CT features are suggestive of WD, no further diagnostic tests are needed for tumor characterization. Moreover, CT can accurately identify most DD, thereby rendering their under-treatment unlikely; however, a CT-guided biopsy is needed to differentiate between DD and WD RPLS that contain focal nodular/water density areas, thereby avoiding their over treatment.”
Computed tomography scan-driven selection of treatment for retroperitoneal liposarcoma histologic subtypes.
Lahat G et al.
Cancer. 2009 Mar 1;115(5):1081-90. - “ Retroperitoneal liposarcoma frequently recurs asymptomatically within 2 years, usually within 6 months-2 years, of the initial surgical resection. The CT features of recurrent liposarcoma are similar to those of the initial manifestation; recurrent liposarcoma shows rapid growth, with a mean tumor volume doubling time of 98 days (range, 46-151 days; median, 104 days).”
Recurrence of retroperitoneal liposarcoma: imaging findings and growth rates at follow-up CT.
Kim EY et al.
AJR 2008 Dec;191(6):1841-6 - “A liposarcoma is a malignant tumor of mesenchymal origin that is one of the most common primary neoplasms in the retroperi- toneum. Liposarcomas rarely arise in the mesentery or peritoneum. The only effective treatment for a retroperitoneal liposarcoma is surgical resection . Unfortunately, surgery is curative in only a minority of patients, and liposarcoma shows a high rate of local recurrence even when surgical mar-
gins are negative for tumor.”
Recurrence of retroperitoneal liposarcoma: imaging findings and growth rates at follow-up CT.
Kim EY et al.
AJR 2008 Dec;191(6):1841-6 - “In our study, well-differentiated recurrent liposarcomas tended to have a more fatty at- tenuation. All of the well-differentiated li- posarcomas (n = 2) and one lesion of a mixed subtype that was well-differentiated, myx- oid, and pleomorphic had mainly fatty com- ponents, whereas most of the myxoid or dedifferentiated liposarcomas (86%, 6/7) manifested as mainly soft-tissue masses. ”
Recurrence of retroperitoneal liposarcoma: imaging findings and growth rates at follow-up CT.
Kim EY et al.
AJR 2008 Dec;191(6):1841-6 - “The CT features of recurrent liposarcoma such as attenuation are similar to those of the initial tumor, with a variety of findings ranging from subtle fatty masses to small well-enhancing nodular lesions. When inter- preting follow-up CT scans of patients who have undergone liposarcoma surgery, one should note the location and CT attenuation of the initial tumor. Because recurrent retro- peritoneal liposarcomas usually grow rapid- ly, a shorter follow-up interval (i.e., 3 months) would be helpful for the early detection of recurrent retroperitoneal liposarcomas.”
Recurrence of retroperitoneal liposarcoma: imaging findings and growth rates at follow-up CT.
Kim EY et al.
AJR 2008 Dec;191(6):1841-6
- “Common presenting symptoms included abdominal pain (n = 8, 27.6%), GI bleeding (n = 5, 17.2%) and symptoms of GI tract obstruction (n = 4, 13.8%). CT scan was the most commonly performed investigation (96.6%). Over half of resections (54.5%, n = 18) included small bowel resection. Mortality at 2 and 5 years was 66.4% and 73.1%. Of the 3 patients who underwent a second resection of GI metastases, one is still alive after 26 months of follow up; 2 patients died after 32.8 and 18.6 months.”
Malignant melanoma of the gastro-intestinal tract: A case series.
Patel K et al.
Int J Surg. 2014 Feb 25 [Epub ahead of print] - “Clinicians should have a low threshold for investigating GI symptoms in patients with a history of malignant melanoma even in the case of early-stage primary disease. Re-resection should be considered in patients presenting with further GI metastases.”
Malignant melanoma of the gastro-intestinal tract: A case series.
Patel K et al.
Int J Surg. 2014 Feb 25 [Epub ahead of print] - “ CT and MRI enterography are comparable first-line modalities for patients with suspected small bowel disease, but magnetic resonance enterography is favored given the absence of ionizing radiation. Capsule endoscopy is a reasonable alternative investigation in exploration of chronic gastrointestinal blood loss, but is best kept as a second-line test in patients with other symptoms.”
Imaging the small bowel.
Murphy KP et al.
Curr Opin Gastroenterol. 2014 Mar;30(2):134-40 - “Fluoroscopic studies such as barium follow through and small bowel enteroclysis are being replaced by the cross-sectional alternatives. Contrast-enhanced ultrasound is showing results comparable with CT and MRI, but concern remains regarding reproducibility, especially outside centres that specialize in advanced sonographic techniques.”
Imaging the small bowel.
Murphy KP et al.
Curr Opin Gastroenterol. 2014 Mar;30(2):134-40 - “ Primary gastrointestinal (GI) lymphoma most often arises from stomach, small bowel, or colon. The 2 most common subtypes of primary GI lymphoma include low-grade mucosa-associated lymphoid tissue lymphoma, strongly associated with Helicobacter pylori infection, and high-grade diffuse, large B-cell lymphoma. Primary GI lymphoma demonstrates a myriad of imaging manifestations that can commonly mimic other pathologies. Timely and accurate diagnosis remains important because treatment and prognosis of primary GI lymphoma differ significantly from other GI malignancies and even lymphoma of other primary sites.”
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65. Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65. - “ Primary gastrointestinal (GI) lymphoma most often arises from stomach, small bowel, or colon. The 2 most common subtypes of primary GI lymphoma include low-grade mucosa-associated lymphoid tissue lymphoma, strongly associated with Helicobacter pylori infection, and high-grade diffuse, large B-cell lymphoma.”
Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65. - “ Primary GI lymphoma demonstrates a myriad of imaging manifestations that can commonly mimic other pathologies. Timely and accurate diagnosis remains important because treatment and prognosis of primary GI lymphoma differ significantly from other GI malignancies and even lymphoma of other primary sites.”
Imaging of primary gastrointestinal lymphoma.
Chang ST, Menias CO
Semin Ultrasound CT MR. 2013 Dec;34(6):558-65.
- “A small bowel mass in a patient with a known malignancy is likely a metastasis; the most common malignancy involving the small bowel is metastatic. Small bowel metastases are categorized by means of spread: Intraperitoneal seeding, hematogenous spread, or local extension.”
CT Evaluation of Small Bowel Neoplasms:Spectrum of Disease
Buckley JA, Fishman EK
RadioGraphics 1998; 18:379-392 - Metastases to the Small Bowel: Sites of Origin
- Melanoma
- Lung cancer
- Carcinoid tumor
- Ovarian cancer
- Colon cancer - Metastases to the Small Bowel: Patterns of Spread
- Intraperitoneal seeding
- Hematogenous metastases
- Direct extension - Metastases to the Small Bowel: Patterns of Spread
- Intraperitoneal seeding
- Mucinous tumors of the ovary, appendix or colon
- Hematogenous metastases
- Lung cancer, breast cancer, malignant melanoma,renal cell carcinoma
- Direct extension
- Pancreatic, biliary or colon cancers 
- “ A subepithelial lesion with a lesion to aorta ratio less than 0.86 in the portal venous phase or not in the gastric antrum or duodenum is never a glomus tumor. On the contrary, a subepithelial lesion with hemangioma like enhancement during dynamic CT is essentially a glomus tumor.”
Gastroduodenal Glomus Tumors: Differentiation From Other Subepithelial Lesions Based on Dynamic Contrast-Enhanced CT Findings
Hur BY et al.
AJR 2011; 197:1351-1359
- Small Bowel Neoplasms
- Relatively Rare
- 1-2% of all GI cancers arise in the small bowel
- ACS: estimated 7570 new cases and 1100 deaths due to small bowel cancer in US in 2011
- The US has among the highest age-adjusted incidence of small bowel tumors, worldwide
- Increase in incidence in the US over last 30 years - Small Bowel Neoplasms
Risks
- Diet.: Eating high-fat foods may raise the risk of small bowel cancer. Regularly consuming smoked or cured foods may also increase a person’s risk.
- Crohn disease.
- Celiac disease.
- Familial adenomatous polyposis (FAP). - Small Bowel Neoplasms
Presentation
- Pain, nausea, vomiting
- Weight loss, obstruction
- GI bleeding
- Lack of reliable clinical findings
- Usually significant delay in diagnosis - Carcinoid Tumor
1. Originate from enterochromaffin cells of the neuroendocrine system
2. Classically categorized based on their origin from embryonic divisions of the alimentary tract
- Foregut (lungs, bronchi, stomach)
- Midgut (small bowel, appendix and proximal colon)
- Hindgut (distal colon and rectum)
3. More recently categorized based on malignancy
- Benign, low grade, high grade-using histological differentiation, size, angioinvasion, & infiltration as criteria - Carcinoid Tumor
- Arise in the bowel wall as a submucosal mass
- Made up of small round regular cells containing a round nucleus and clear cytoplasm. Histologic diagnosis also relies on immunohistochemical stains and electron microscopy.
- The presence of elevated excretion of 5-hydroxyindoleacetic acid (5-HIAA) is suggestive of a functioning carcinoid tumor. - Gastrointestinal Stromal Tumors
- Mesenchymal tumors which typically arise in association with with the muscularis propria of gastrointestinal tract wall
- Most frequent in the stomach (60%), but also can occur in the small bowel (30%) or elsewhere, including the colon and rectum (5%), esophagus (<5%)
- 5% of small bowel malignancies - Gastrointestinal Stromal Tumors
- Most occur 50-60 years ( rare < 40)
- Can be familial (present often in 30’s)
Symptoms
- GI bleeding, anemia, abdominal pain, dyspepsia, palpable abdominal mass.
- Nishida et al, 271 patients with stromal tumors, 2/3 had symptoms that correlated with tumors size. Tumors > 3 cm were more likely to demonstrate necrosis than tumors < 3 cm.
- Obstruction is rare. Burkhill et al, 1/ 61 SBO - Gastrointestinal Stromal Tumors
- Arise pathologically from the wall of the GI tract and can be characterized as benign, borderline, low or high malignant potential based on the pathologic appearance.
- The vast majority express a mutant form of c-kit (CD117) that can be detected on routine staining.
- C-kit is a growth factor receptor with tyrosine kinase activity. It is thought that mutations in the c-kit gene are causative for the development of gastrointestinal tumors. It is found in both benign and malignant GIST. - Gastrointestinal Stromal Tumors
- Characterized as benign, borderline, low or high malignant potential based on the pathologic appearance.
- The vast majority express a mutant form of c-kit (CD117) that can be detected on routine staining.
- C-kit is a growth factor receptor with tyrosine kinase activity. It is thought that mutations in the c-kit gene are causative for the development of gastrointestinal - GIST
CT Findings
- intramural mass when small
- Can grow endoluminal or exophytic
- often central ulceration and /or necrosis
- do not usually produce significant adenopathy
- 3D CT is especially useful in determine organ of origin - Gastrointestinal Stromal Tumors
10-30% are malignant
Malignant risk increases with
- Extragastric location
- Size > 5cm
- Extension into adjacent organs
- > 1 mitosis per 50 high powered field
- Duodenal Carcinoids: Facts
- Most common in second portion duodenum
- May be multiple
- Enhancement is common
- More common in patients with neurofibromatosis type I where lesions were periampullary
- Usually intraluminal polyp or a mural mass - “The CT features of an enhancing duodenal mass during the early phases of contrast
enhancement is suggestive of the possibility of a carcinoid.”
Duodenal Carcinoids: Imaging Features with Clinical-Pathologic Comparison
Levy AD et al.
Radiology 2005; 237:967-972 - “Duodenal carcinoids are distinctly different tumors compared with their counterparts in the
jejunum and ileum. Unlike duodenal carcinoids, jejunal and ileal carcinoids arise from serotonin
producing enterochromaffin cells and commonly manifest imaging evidence of local serotonin
production and bowel kinking, mesenteric desmoplasia, elastic vascular sclerosis and intestinal
ischemia.”
Duodenal Carcinoids: Imaging Features with Clinical-Pathologic Comparison
Levy AD et al.
Radiology 2005; 237:967-972 - “ Duodenal carcinoids are neuroendocrine tumors that encompass a wide clinico-pathologic
spectrum of hormonally functioning and nonfunctioning tumors that differ from jejunal and ileal
carcinoids.”
Duodenal Carcinoids: Imaging Features with Clinical-Pathologic Comparison
Levy AD et al.
Radiology 2005; 237:967-972 - “ Duodenal carcinoids are uncommon tumors with a wide clinical-pathologic spectrum. They
occur most commonly in the proximal duodenum and manifest as an intraluminal polyp or a
mural mass.”
Duodenal Carcinoids: Imaging Features with Clinical-Pathologic Comparison
Levy AD et al.
Radiology 2005; 237:967-972 - “ The gastrointestinal tract is the most common extranodal site of involvement in NHL, with
disease seen at some site in up to 20% of patients.”
Extranodal Lymphoma From Head to Toe;Part 2, The Trunk and Extremities
Thomas AG et al
AJR 2011;197:357-364 - Small Bowel Lymphoma: Facts
- Primary small bowel lymphoma is usually of B-cell origin
- More common in distal ileum due to increased lymphoid tissue
- May present on CT as;
- Infiltrative disease
- Aneurysmal dilatation
- Nodular feeling defects
- Endo-exenteric form with fistulae - Primary GI Lymphoma
- Sites of involvement in decreasing order of frequency are stomach, small bowel, colon and
esophagus
- Usually MALT tumors (mucosa associated lymphoid tissue lymphoma).
- T-cell lymphomas are particularly prone to bowel wall involvement of the ileum and
jejunum. They are aggressive and have higher rates of bowel perforation. - “ A distinction is made between primary gastrointestinal tract lymphoma, in which there is little
retroperitoneal lymphadenopathy or hepatomegaly, and involvement of the gastrointestinal tract
in disseminated NHL from other body sites.”
Extranodal Lymphoma From Head to Toe;Part 2, The Trunk and Extremities
Thomas AG et al
AJR 2011;197:357-364 - “ Identification of a mass clearly visible suggests strongly the presence of small bowel adenocarcinoma in Crohn disease patients but adenocarcinoma may be completely indistinguishable from benign fibrotic or acute inflammatory stricture. Knowledge of these findings is critical to help suggest the diagnosis of this rare but severe complication of Crohn disease.”
Small Bowel Adenocrcinoma in crohn Disease:CT-Enterography Features with Pathological Correlation
Soyer P, Hristova L, Boudghene F, Hoeffel C, Dray X, Laurent V, Fishman EK, Boudiaf M
Abdom Imaging 2011 June 14 (Epub ahead of print) - “ Imaging of small bowel NET,even with combinations of CT,MR and radionuclide studies, underestimates the extent of peritoneal, mesenteric, and hepatic metastatic disease. Accurate staging of small bowel NET might be best performed at the time of laparotomy.”
Role of imaging in the preoperative staging of small bowel neuroendocrine tumors
Chambers AJ et al.
J Am Coll Surg, 2010 Nov;211(5):620-627 - “CT enteroclysis has the potential to be an excellent diagnostic method for the examination of carcinoid small-bowel tumors. It provides adequate image quality with multiplanar reformations, allows sufficient distention of the entire small bowel, and provides detailed information about small-bowel masses (size, location, and enhancement) and extraenteric abnormalities (liver metastasis, lymph nodes, and peritoneal metastasis).”
Value of CT Enteroclysis in Suspected Small-Bowel Carcinoid Tumors
Kamaoui I et al.
AJR 2010;194:629-633 - “The overall sensitivity and specificity of CT enteroclysis in identifying patients with small-bowel carcinoid tumors were 100% and 96.2%, respectively. The negative predictive value of CT enteroclysis was 100% and the positive predictive value, 94.7%. Pathologic findings confirmed small-bowel carcinoid tumors in 18 patients.”
Value of CT Enteroclysis in Suspected Small-Bowel Carcinoid Tumors
Kamaoui I et al.
AJR 2010;194:629-633 - “ CT enteroclysis findings were positive in 19 patients and negative in 25 patients. The sizes of the carcinoid tumors identified were 5-30 mm in axial diameter. These tumors were depicted as focal nodular lesions located in the small-bowel wall or as intraluminal polypoid masses with marked enhancement.”
Value of CT Enteroclysis in Suspected Small-Bowel Carcinoid Tumors
Kamaoui I et al.
AJR 2010;194:629-633 - “ CT enteroclysis findings were positive in 19 patients and negative in 25 patients. The sizes of the carcinoid tumors identified were 5-30 mm in axial diameter. These tumors were depicted as focal nodular lesions located in the small-bowel wall or as intraluminal polypoid masses with marked enhancement. Twenty-two patients underwent only clinical follow-up, with a mean clinical follow-up time of 20 months. The overall sensitivity and specificity of CT enteroclysis in identifying patients with small-bowel carcinoid tumors were 100% and 96.2%, respectively. The negative predictive value of CT enteroclysis was 100% and the positive predictive value, 94.7%. Pathologic findings confirmed small-bowel carcinoid tumors in 18 patients.”
Value of CT Enteroclysis in Suspected Small-Bowel Carcinoid Tumors
Kamaoui I et al.
AJR 2010;194:629-633 - “At our institution, 44 patients with symptoms of suspected gastrointestinal carcinoid tumors underwent CT enteroclysis. Positive CT enteroclysis findings were compared with pathology results after surgical procedures (n = 19). Negative examinations were compared with surgery results (n = 3) or clinical follow-up (n = 22).”
Value of CT Enteroclysis in Suspected Small-Bowel Carcinoid Tumors
Kamaoui I et al.
AJR 2010;194:629-633 - “At our institution, 44 patients with symptoms of suspected gastrointestinal carcinoid tumors underwent CT enteroclysis. Clinical symptoms were as follows: carcinoid syndrome (n = 3), abdominal pain with diarrhea (n = 24), hypervascular liver metastases (n = 7), subileus condition (n = 1), hypervascular peritoneal lesion (n = 3), abnormal ileal stenosis on optical colonoscopy (n = 3), and follow-up extraintestinal carcinoid lesion (n = 3). Positive CT enteroclysis findings were compared with pathology results after surgical procedures (n = 19). Negative examinations were compared with surgery results (n = 3) or clinical follow-up (n = 22).”
Value of CT Enteroclysis in Suspected Small-Bowel Carcinoid Tumors
Kamaoui I et al.
AJR 2010;194:629-633 - CTA of the Small Bowel: Scan Protocol
Oral contrast
-Water
-Omnipaque-350
-VoLumen
Intravenous contrast
-100-120 cc of Omnipaque -350
-Injection rate of 3-5 cc/sec - Carcinoid Tumor: CT Findings
-Primary mass in bowel or in the mesentery
-Desmoplastic reaction in the mesentery
-Calcification of mesenteric mass
-Liver metastasis (hypervascular) - Carcinoid Tumor of the Small Bowel: Facts
-Tumor metastases occur in less than 2% of primary tumors <1 cm but in 85% of cases in tumors over 2 cm
-Ileal tumors are most likely to metastasize
-Over 90% of cases arise in the ileum - Carcinoid Tumor of the Small Bowel: Facts
-Tumors secrete serotonin which is metabolized by the liver to 5-HIAA and excreted in the urine
-Liver metastases seen in over 90% of patients with the carcinoid syndrome
-Liver metastases are usually hypervascular - Carcinoid Syndrome:
GI Manifestations
- Chronic diarrhea
- Intestinal colic
- Malabsorption syndrome
- Small bowel ischemia and/or infarction (Carcinoid tumors can lead to mesenteric ischemia and infarction due to the tumors desmoplastic reaction and subsequent encasement of blood vessels (arterial and venous)) - Carcinoid Tumor of the Small Bowel: Facts
-Most common in ileum and least common in duodenum
- Average incidence in US is around 1 in 100,000 cases
-More common in men
-More common in African-Americans and lower for Hispanics
- Epidemiology of cancer of the small intestine
Pan SI, Morrison H
World J Gastrointest Oncol 2011 March 15; 3(3):33-42 - Small Bowel Tumors: Frequency
- Adenocarcinoma 30-40%
-Carcinoid tumors 35-42%
- Lymphoma 15-20%
- Sarcomas 15-20% - Metastatic disease
-Melanoma
- Renal cancer - Small Bowel Tumors: Malignant
Primary tumors
-Adenocarcinoma
-Lymphoma
-Carcinoid
-GIST (gastrointestinal stromal tumors) - “Cancer of the small intestine is very uncommon. There are 4 main histological subtypes: adenocarcinomas, carcinoid tumors, lymphoma and sarcoma. The incidence of small intestine cancer has increased over the past several decades with a four-fold increase for carcinoid tumors, less dramatic rises for adenocarcinoma and lymphoma and stable sarcoma rates.”
Epidemiology of cancer of the small intestine
Pan SI, Morrison H
World J Gastrointest Oncol 2011 March 15; 3(3):33-42 - Hypervascular Metastases to the GI Tract: Facts
- Primary sites are most commonly melanoma and breast cancer
- Less common sites of origin include renal cell carcinoma, choriocarcinoma, neuroendocrine tumors, mesenchymal sarcoma - Glomus Tumors: Facts
- GI glomus tumors are nearly always in the stomach
- Represent under 2% of all benign gastric tumors
- Usually under 3 cm in size
- Very vascular especially on arterial phase imaging - GIST Tumors: Facts
Site of origin
- Stomach 60-70% of cases
- Small bowel 30% of cases
- Rectum, esophagus, colon and appendix are rare sites of tumor - Neuroendocrine Tumors in the GI Tract: Facts
- Appendix most common location
- Small bowel is second most common location
- Carcinoid syndrome occurs in less tha 10% of patients with neuroendocrine tumor
- Classic carcinoid syndrome (flushing and diarrhea) does not occur without liver metastases
- Metastases relate to size of primary tumor
- 30% of small bowel carcinoids are multicentric "A subepithelial mass, which was previously called a submucosal mass, is defined as a mass covered with normal appearing mucosa, whether the underlying process is intramural or extramural in origin."
Hypervascular Subepithelial Gastrointestinal Masses: CT-Pathologic Correlation
Lee NK et al.
RadioGraphics 2010; 30:1915-1934- Hypervascular Subepithelial GI Masses: Differential Dx
- Neuroendocrine tumors
- GI stromal tumors
- Glomus tumor
- Hemangioma
- Angiosarcoma
- Kaposi sarcoma
- Hypervascular metastases
- Heterotopic tissues
- Vascular structures "The overall sensitivity and specificity of CT enteroclysis in identifying patients with small bowel carcinoid tumors were 100% and 96.2%, respectively. The negative predictive value of CT enteroclysis was 100% and the positive predictive value,94.7%."
Value of CT Enteroclysis in Suspected Small Bowel Carcinoid Tumors
Kamaoui I et al.
AJR 2010; 194:629-633- Small Bowel GIST Tumors: Differential Diagnosis
- GIST
- Lymphoma
- Adenocarcinoma
- Metastatic disease - Small Bowel: GIST Tumors: Facts
Patients with neurofibromatosis I have an increased incidence of GIST’s and may have multiple GIST’s - Small Bowel: GIST Tumors: Location
- Stomach 70%
- Small intestine 20-30%
- Rectum
- Colon
- Esophagus - "In conclusion, we found that CT features, other than tumor size, cannot helpfully predict GIST malignancy and that the malignant potential of small GIST tumors (<5cm) cannot be determined on CT."
Gastrointestinal Stromal Tumors of the Stomach: CT Findings and Prediction of Malignancy
Kim HC et al.
AJR 2004;183:893-898 - Small Bowel: GIST Tumors: Clinical Presentation
- GI bleeding from mucosal ulceration
- Hematemesis, melena, anemia
- Abdominal pain or discomfort
- Incidental finding on CT exam - Small Bowel: Malignant GIST vs Benign GIST Tumor
- Malignant tumors were usually predominately extraluminal, heterogeneous and necrotic
- Benign tumors were usually endoluminal, homgeneous and smooth or ovoid - "Although presence of an ulcer, mesenteric fat infiltration, direct organ invasion, and metastases were more frequently observed in tumors with a high mitotic rate, no CT feature, other than size, was found to have predictive value with respect to malignant GIST tumors of the stomach."
Gastrointestinal Stromal Tumors of the Stomach: CT Findings and Prediction of Malignancy
Kim HC et al.
AJR 2004;183:893-898 - MDST of the Small Bowel: Study Protocol and Design
- MDCT 64 slice scanner
- .6 mm collimation
- .6-.75 mm slice thickness
- .4-.5 mm interval reconstructions - "It is important for the radiologist to be familiar with the CT appearance of various small bowel tumors and the value of utilizing 3D imaging for diagnosis and for surgical planning."
Multidetector-Row Computed Tomography and 3-Dimensional Computed Tomography Imaging of Small Bowel Neoplasms
Horton KM, Fishman EK
J Comput Assist Tomogr 2004;28:106-116