Imaging Pearls ❯ Pancreas ❯ Missed Diagnosis
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- Purpose: Accurate staging of disease is vital in determining appropriate care for patients with pancreatic ductal adenocarcinoma (PDAC). It has been shown that the quality of scans and the experience of a radiologist can impact computed tomography (CT) based assessment of disease. The aim of the current study was to evaluate the impact of the rereading of outside hospital (OH) CT by an expert radiologist and a repeat pancreatic protocol CT (PPCT) on staging of disease.
Conclusion: A repeat PPCT results in increased detection of metastatic disease that rereviews of OH scans may otherwise miss. Accessible insurance coverage for repeat PPCT imaging even within 30 days of an OH scan could help optimize delivery of care and alleviate burdens associated with misstaging.
Factors associated with radiological misstaging of pancreatic ductal adenocarcinoma: A retrospective observational study.
Yasrab M, Thakker S, Wright MJ, Ahmed T, He J, Wolfgang CL, Chu LC, Weiss MJ, Kawamoto S, Johnson PT, Fishman EK, Javed AA
Curr Probl Diagn Radiol. 2024 Mar 7:S0363-0188(24)00047-1. doi: 10.1067/j.cpradiol.2024.03.001. Epub ahead of print. PMID: 38522966. - “Pancreatic imaging, however, has its pitfalls and challenges, which are driven in part by the type and quality of the scanners, expertise of the technologists, and the experience of the radiologists interpreting these images.11 Misstaging of disease has clinical implications for patient care; for instance, in the event of undetected metastases, surgical resection is aborted intraoperatively. The current rate of occult metastatic disease has been estimated to range from 8 % to 24.5 %.”
Factors associated with radiological misstaging of pancreatic ductal adenocarcinoma: A retrospective observational study.
Yasrab M, Thakker S, Wright MJ, Ahmed T, He J, Wolfgang CL, Chu LC, Weiss MJ, Kawamoto S, Johnson PT, Fishman EK, Javed AA
Curr Probl Diagn Radiol. 2024 Mar 7:S0363-0188(24)00047-1. doi: 10.1067/j.cpradiol.2024.03.001. Epub ahead of print. PMID: 38522966. - “Rereading an OH scan by an experienced radiologist caught previously missed metastatic disease in 21.5 % (11/51) of those who were misstaged. When the OH scan was compared directly to a PPCT, it resulted in the most prominent change in terms of absolute numbers (70/100) with 35.7 % (25/70) cases of missed metastatic disease. While rereviewing an OH scan results in led to a higher total number of misstaged cases, it still did not fully capture the absolute number of patients with occult metastatic disease that a repeat PPCT detected. This is showcased when comparing the OH scan rereviews to the PPCT, which reveals that missed metastases comprise the bulk of misstaged cases 62.5 % (15/24) that a reread did not pick up.”
Factors associated with radiological misstaging of pancreatic ductal adenocarcinoma: A retrospective observational study.
Yasrab M, Thakker S, Wright MJ, Ahmed T, He J, Wolfgang CL, Chu LC, Weiss MJ, Kawamoto S, Johnson PT, Fishman EK, Javed AA
Curr Probl Diagn Radiol. 2024 Mar 7:S0363-0188(24)00047-1. doi: 10.1067/j.cpradiol.2024.03.001. Epub ahead of print. PMID: 38522966. - “In conclusion, this study redemonstrates the need for adherence to protocols for PPCT when assessing patients with PDAC. Furthermore, in the event of a suboptimal scan, a repeat PPCT is warranted, even if performed within 30 days of a prior scan, given the risk of missing metastatic disease. Increased utilization of PPCT, standardized templates, expert radiologist rereads, and insurance coverage for reimaging could help alleviate the psychological and financial burdens associated with misstaging of disease on both the patients and the healthcare system. ”
Factors associated with radiological misstaging of pancreatic ductal adenocarcinoma: A retrospective observational study.
Yasrab M, Thakker S, Wright MJ, Ahmed T, He J, Wolfgang CL, Chu LC, Weiss MJ, Kawamoto S, Johnson PT, Fishman EK, Javed AA
Curr Probl Diagn Radiol. 2024 Mar 7:S0363-0188(24)00047-1. doi: 10.1067/j.cpradiol.2024.03.001. Epub ahead of print. PMID: 38522966.
- “Radiological features as pancreatic duct dilation and interruption, and focal atrophy are common first signs of PDAC and are often missed or unrecognized. Further investigation with dedicated pancreas imaging is warranted in patients with PDAC-related radiological findings.”
Prevalence, features, and explanations of missed and misinterpreted pancreatic cancer on imaging: a matched case–control study
Sanne A. Hoogenboom et al.
Abdominal Radiology 2022 (in press) https://doi.org/10.1007/s00261-022-03671-6 - “As stated earlier, PanIN with high-grade dysplasia and early invasive PDAC lesions do not generally form clear hypodense masses. Still, they may cause visible changes of the pancreatic parenchyma and the pancreatic duct, and these changes are rarely observed in patients who do not subsequently develop PDAC, as demonstrated in this study. Focal parenchymal atrophy may be a less known PDAC related imaging feature, but was observed on CT and MRI in 46%–49% of cases and only in one control patient. These results confirm the conclusion of recently published papers, who recognized focal atrophy as one of the first radiological features of early-stage PDAC.”
Prevalence, features, and explanations of missed and misinterpreted pancreatic cancer on imaging: a matched case–control study
Sanne A. Hoogenboom et al.
Abdominal Radiology 2022 (in press) https://doi.org/10.1007/s00261-022-03671-6 - “Current practice may underestimate the importance of these secondary findings, especially in the absence of a distinct mass. For patients with PD dilation, interruption, and focal atrophy, thorough examination (e.g., dedicated pancreas imaging with MRI/ MRCP, CT or endoscopic ultrasound) and close follow-up is recommended.”
Prevalence, features, and explanations of missed and misinterpreted pancreatic cancer on imaging: a matched case–control study
Sanne A. Hoogenboom et al.
Abdominal Radiology 2022 (in press) https://doi.org/10.1007/s00261-022-03671-6 - “Approximately 35% of the reassessed CTs in this study were obtained without contrast, which may have restricted the radiologists’ ability to assess the presence of lesions and secondary signs. This represents a real world scenario, in which unfortunately not all opportunities to detect pre-diagnostic pancreatic cancer will be according to ideal imaging protocols. When pancreas pathology is suspected, the next immediate step after substandard imaging would be to follow-up with the optimal CT and MRI protocols for assessing the pancreas according to society recommendations.”
Prevalence, features, and explanations of missed and misinterpreted pancreatic cancer on imaging: a matched case–control study
Sanne A. Hoogenboom et al.
Abdominal Radiology 2022 (in press) https://doi.org/10.1007/s00261-022-03671-6 - “FPPA occurred in 28% of the PDAC group at 35 months prediagnosis. The FPPA area resolved before PDAC onset. Benchmarking previous images of the pancreas with the focus on FPPA may enable prediction of PDAC. PDAC with FPPA involves widespread high-grade pancreatic intraepithelial neoplasia requiring a wide surgical margin for surgical excision.”
Focal pancreatic parenchyma atrophy is a harbinger of pancreatic cancer and a clue to the intraductal spreading subtype
Jun Nakahodo et al.
Pancreatology 2022 (in press) - “Despite these limitations, our study demonstrated that FPPA was present before the clinical onset of pancreatic cancer in a significant proportion of the patients. Some asymptomatic cases of pancreatic cancer may potentially be detected earlier if clinicians are vigilant in their assessment of the patient’s pancreatic health. In line with the results of previous studies, our results indicated that FPPA is a precancerous finding in some cases of pancreatic cancer. Our findings may significantly improve the accuracy of diagnosing PDAC before symptom onset and provide the basis for a future large-scale, multicentric, prospective study. In conclusion, at least 30% of PDAC cases exhibited atrophy before diagnosis. In many cases, PDAC was able to be predicted by benchmarking retrospective images of FPPA findings using past imaging studies to create a timeline. Filling of the atrophy area is likely to indicate the presence of invasive cancer, which may help identify asymptomatic PDAC. A sufficiently wide margin including the atrophic area should be created when performing surgery as the lesions tend to spread widely.”
Focal pancreatic parenchyma atrophy is a harbinger of pancreatic cancer and a clue to the intraductal spreading subtype
Jun Nakahodo et al.
Pancreatology 2022 (in press) - “Perivascular soft tissue may be observed following pancreaticoduodenectomy in both malignant and benign etiologies, and the long- or short-axis diameter and enhancement pattern may not help in differentiating malignant versus benign perivascular soft tissue. Benign portal vein stenosis has been described in up to 26–84% of first postoperative CTs of patients who underwent pancreaticoduodenectomy for PDAC and is especially common in patients who required portomesenteric venous resection and reconstruction. While benign portal vein stenosis gradually resolves or remains stable in most patients, the portal vein stenosis associated with tumor recurrence is usually progressive and may develop after the initial postoperative CT.”
Postoperative surveillance of pancreatic ductal adenocarcinoma (PDAC) recurrence: practice pattern on standardized imaging and reporting from the society of abdominal radiology disease focus panel on PDAC
Linda C. Chu et al.
Abdominal Radiology 2022 (in press) - “The recommended surveillance interval during the first year for patients at high risk of recurrence is every 3 months or less (S3Q7, 85.7%). The surveillance interval during the first year for patients at low risk of recurrence failed to reach consensus, with 66.7% of panelists favoring every 4–6 months and 33.3% of panelists favoring every 3 months or less (S3Q8). The panelists failed to reach consensus for surveillance interval during the second year for patients at high risk of recurrence, with 71.4% of panelists favoring every 4–6 months and 28.6% of panelists favoring every 3 months or less (S3Q9). The panelists agreed that the surveillance interval during the second year for patients at low risk of recurrence should be every 4–6 months (S3Q10, 95.2%).”
Postoperative surveillance of pancreatic ductal adenocarcinoma (PDAC) recurrence: practice pattern on standardized imaging and reporting from the society of abdominal radiology disease focus panel on PDAC
Linda C. Chu et al.
Abdominal Radiology 2022 (in press) - "Postoperative imaging following PDAC resection is challenging to interpret due to the presence of confounding postoperative inflammatory changes, which may be further exacerbated by the adjuvant or neoadjuvant treatmentinduced fibrosis. Some of the existing guidelines address recommended imaging surveillance intervals but do not provide guidance about the risk of recurrence based on specific imaging features. This SAR PDAC DFP consensus document aims to begin the groundwork for defining imaging features that should be considered suspicious for tumor recurrence. These imaging findings should be interpreted in conjunction with CA19-9 to improve specificity. Future work is needed to standardize the lexicon in describing postoperative findings to refine the tumor recurrence risk assessment.”
Postoperative surveillance of pancreatic ductal adenocarcinoma (PDAC) recurrence: practice pattern on standardized imaging and reporting from the society of abdominal radiology disease focus panel on PDAC
Linda C. Chu et al.
Abdominal Radiology 2022 (in press)
- “The long-term risk of pancreatic malignancy in asymptomatic patients with incidental pancreatic cysts less than 2 cm is 0.9 cases per 1,000 patient-years of follow-up, similar to those without pancreatic cysts. These very few pancreatic cancers developed at a separate location from the known cyst.”
Incidence of pancreatic cancer during long‐term follow‐up in patients with incidental pancreatic cysts smaller than 2 cm
Masoud Nakhaei et al.
European Radiology https://doi.org/10.1007/s00330-021-08428-1 - Key Points
• After a median of 9.2 years of follow-up, the risk of pancreatic malignancy in patients with an asymptomatic small pan- creatic cyst was 0.9 cases per 1,000 patient-years of follow-up, similar to those without pancreatic cysts.
• Very few pancreatic cancer cases developed in the location separate from the known pancreatic cyst.
Incidence of pancreatic cancer during long‐term follow‐up in patients with incidental pancreatic cysts smaller than 2 cm
Masoud Nakhaei et al.
European Radiology https://doi.org/10.1007/s00330-021-08428-1 - "In conclusion, our study showed that the long-term risk of developing pancreatic cancer in asymptomatic patients with small (< 2 cm) pancreatic cysts appears to be similar to the population of patients without pancreatic cysts. This result can guide modification of the existing guidelines to reduce the frequency of imaging follow-up or even alleviate the need for follow-up completely in asymptomatic patients with small pancreatic cysts to reduce the induced anxiety of patients and the time/cost burden to the health care system.”
Incidence of pancreatic cancer during long‐term follow‐up in patients with incidental pancreatic cysts smaller than 2 cm
Masoud Nakhaei et al.
European Radiology https://doi.org/10.1007/s00330-021-08428-1
- Errors in the Diagnosis of Pancreatic Cancer
- Small tumor size
- Tumor is isodense to the pancreas
- Missed pancreatic duct cutoff sign
- Underlying chronic pancreatitis - Errors in the Diagnosis of Pancreatic Cancer
- Confusion of duodenal mass as pancreatic mass (GIST, Adenocarcinoma, Carcinoid)
- Adenopathy especially portocaval nodes (lymphoma)
- Adrenal or retroperitoneal mass near pancreas
- Metastases to the pancreas (kidney, lung, breast primary)
- Autoimmune pancreatitis (false positive) - “Missed imaging diagnosis of PDAC can be minimized by increasing awareness of the secondary signs identified in subtle or isoattenuating tumors, prompting further diagnostic workup rather than follow-up imaging. Uncinate process PDAC can be easily missed at its early stage due to the lack of pancreatic and bile duct dilatation. By using different imaging modalities the radiologists can play a pivotal role in determining tumor resectability, aiding proper surgical planning and evaluating tumor response to treatment. It is also important for the radiologist to know the mimics of PDAC to avoid unnecessary surgery for benign entities such as focal fat infiltration, autoimmune, and groove pancreatitis, and to arrange for proper treatments in malignant tumors such as PNET, lymphoma, and metastasis.”
Imaging diagnosis and staging of pancreatic ductal adenocarcinoma: a comprehensive review
Khaled Y. Elbanna , Hyun-Jung Jang and Tae Kyoung Kim
Insights into Imaging (2020) 11:58 - Key Points
Question: Is there an association of diabetes duration and recent weight loss with subsequent risk of pancreatic cancer?
Findings: In this cohort study of 112 818 women and 46 207 men enrolled in 2 US cohort studies, participants with recent-onset diabetes accompanied by weight loss of 1 to 8 lb or more than 8 lb had a substantially increased risk for pancreatic cancer compared with participants with no such exposure.
Meaning: The findings from this study suggest that individuals with recent-onset diabetes accompanied by weight loss have a high risk for developing pancreatic cancer and may be a group for whom early detection strategies would be advantageous.
Diabetes, Weight Change, and Pancreatic Cancer Risk.
Yuan C, Babic A, Khalaf N, et al.
JAMA Oncol. Published online August 13, 2020. doi:10.1001/jamaoncol.2020.2948
- “In addition to traditional methods, cinematic rendering (CR) as a novel 3D rendering technique can be used to generate photorealistic with more accurate information regarding the anatomical details. CR can assist clinicians to visualize precisely the extent of tumor vascular invasion, which might be critical for surgical planning; however, the feasibility of this method and other novel techniques in routine clinical practice is yet to be studied.”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - “The survival of patients with small PDACs (particularly ≤ 20 mm), 30% at 5 years, is better than it is for patients with larger cancers. However, small tumors are the most difficult to visualize and the sensitivity of MDCT is lower for detection of small PDACs. In a retrospective study by Yoon et al. with 33 PDAC patients who underwent CT prior to the diagnosis of PDAC, the tumor could be identified in 72.7% (24/33) of cases. Of these prospectively missed cases, 87.5% (21/24) were ≤ 20 mm and 12.5% (3/24) were between 21 and 33 mm.”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - “Regarding the secondary signs, the presence of common bile duct and main pancreatic ductal dilatation, pancreatic ductal caliber change and abrupt duct cut-off at the level of the tumor, abnormal pancreas contour, pancreatic atrophy, and pancreatitis are highly suspicious for small PDACs, even in the absence of a clearly defined mass. Yoon et al. showed that secondary signs could be a solution to the concerns associated with detecting small PDACs. They demonstrated that 76% of small PDAC had secondary signs—with main pancreatic duct or common bile duct dilatation (63%), abrupt pancreatic duct cut-off (63%), parenchymal atrophy (21%), and contour abnormality (14%).”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - "PDACs can sometimes be isoenhancing, and when they are, they are often misdiagnosed or unrecognized. Isoenhancing mass is defined as a lesion with an attenuation difference of < 15 HU in comparison with background parenchyma in all phases. It has been shown that 5–45% of PDACs are isoattenuating relative to the remainder pancreatic parenchyma on both late arterial and portal venous phases. Isoenhancement is more commonly seen in smaller tumors, which make the diagnosis even more challenging. It should be noted that small isoattenuating PDAC should not be regarded as early cancers, since only a small proportion of these lesions are stage T1 tumors."
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - “Among secondary imaging features of PDAC, we emphasized the importance of irregularities of the main pancreatic duct. The pancreatic duct needs to be carefully evaluated for any subtle contour irregularities, filling defects, or obstructive lesions. Several case reports have documented patients suspected to PDAC who were believed to have normal findings on previous MDCT and MRI, but subtle pancreatic duct irregularity was found in the re-assessment of prior images or endoscopic retrograde cholangiopancreatography (ERCP). From our experience, subtle pancreatic duct irregularity may be best shown on oblique coronal and sagittal MPR CT (and MR) images that optimizes visualization of the pancreatic duct.”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - “In addition, elevated IgG4 levels suggest AIP, but IgG4 can be normal in some AIP patients and normal serum IgG4 does not exclude AIP. As part of both diagnosis and treatment, most AIP patients show excellent response to steroids. The imaging features of focal pancreatitis including focal AIP, acute pancreatitis, and chronic pancreatitis can mimic a focal mass, and the possible interpretation errors are discussed in the next sections.”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - “Metastases to the pancreas are most commonly from cancers of the kidney, lung, breast and colorectal, and from melanoma. Overall, 15–44% of pancreatic metastases have a diffuse morphological pattern. The appearance of pancreatic metastases can be similar to primary PDAC on MDCT. Pancreatic metastases often show peripheral or homogeneous (less common) enhance- ment; while PDACs are generally hypoattenuating lesions.”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - “IPMNs account for 20% of all cystic pancreatic neoplasms and are divided into main-duct, branch-duct, and mixed subtypes. Most IPMNs are incidentally detected on cross-sectional imaging performed for other clinical indications, and it has been estimated that half of the incidentally detected pancreatic cysts are IPMNs. As pre-cancerous lesions, IPMNs can progress to higher grades of dysplasia and to invasive PDAC, which results in the coexisting malignancy rate of 12–68%. In this regard, the precise diagnosis of PDAC arising from IPMN is of importance, since 10% of diagnosed PDACs are related to the underlying IPMNs.”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - "MDCT is one of the most commonly used imaging modalities for the initial evaluation of suspected PDAC. Several pitfalls are associated with diagnoses of PDAC using MDCT. Optimal imaging technique is key to the detection of subtle cases, and errors in each step of image acquisition carry a potential for contributing to misdiagnosis. Accurate diagnosis requires familiarity with a variety of factors that can lead to interpretation errors. Detection of PDAC can be challenging due to intrinsic tumor features and presence of coexisting pathology that can distract the radiologist from the more subtle lesions. Normal structures and non-neoplastic diseases can also mimic the imaging appearance of PDAC. Recognition and mitigation of such technical and interpretation errors can help early PDAC diagnosis and improve patient prognosis.”
Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors
Arya Haj‐Mirzaian · Satomi Kawamoto · Atif Zaheer · Ralph H. Hruban · Elliot K. Fishman · Linda C. Chu
Abdominal Radiology 2020 (in press) - Mimickers of PDAC: Differetial Diagnosis
- Focal fatty infiltration
- Intrapancreatic accessory spleen (IPAS)
- Pancreatitis
- Background: Accurate assessment of local resectability of pancreatic cancer at initial workup is critical to determine the most appropriate management strategy among up-front operation, neoadjuvant treatment, or palliative treatment.
Purpose: To investigate the interobserver agreement of the preoperative CT classification of the local resectability of pancreatic cancer and to determine if radiologist experience level impacts evaluation, and to evaluate the reader performance in assessing resectability at CT in a subset of patients with a reference standard for local resectability.
Conclusion: Considerable interobserver variability exists in the assignment at CT of the local resectability of pancreatic cancer, even among experienced radiologists.
Preoperative CT Classification of the Resectability of Pancreatic Cancer: Interobserver Agreement
Joo I et al.
Radiology 2019; 00:1–7 • https://doi.org/10.1148/radiol.2019190422 - Results: There were 110 patients (mean age, 61 years 6 +/-11; 60 men) who were evaluated. Overall interobserver agreements were moderate for resectability classification (k = 0.48; 95% confidence interval: 0.45, 0.50). Only 30.0% of patients (33 of 110) were given the same resectability classification from all reviewers. More experienced reviewers demonstrated higher agreement in category assignments than less experienced reviewers (k = 0.55 [95% confidence interval: 0.50, 0.60] vs 0.43 [95% confidence interval: 0.38, 0.49], respectively). For prediction at CT of margin-negative (ie, R0) resections (n = 82), areas under the receiver operating characteristic curve of all reviewers were greater than 0.80 (range, 0.83–0.96). However, borderline resectable cancers showed di- verse R0 rates ranging from 0% to 74% depending on the reviewers.
Conclusion: Considerable interobserver variability exists in the assignment at CT of the local resectability of pancreatic cancer, even among experienced radiologists.
Preoperative CT Classification of the Resectability of Pancreatic Cancer: Interobserver Agreement
Joo I et al.
Radiology 2019; 00:1–7 • https://doi.org/10.1148/radiol.2019190422 - Key Results
* Classification at CT of pancreatic cancer as resectable, borderline resectable, or unresectable shows substantial interob- server variability (k = 0.48). Only 30.0% (33 of 110) of patients received consistent resectability classification by all eight reviewers.
* Prediction at CT of local resectability of pancreatic cancer shows area under the receiver operating characteristic curve values greater than 0.80 (range, 0.83–0.96 depending on reviewers) by using a three-category classification. More experienced reviewers have higher agreement for category assignments than less experienced reviewers (k = 0.55 vs 0.43, respectively; P = .001).
Preoperative CT Classification of the Resectability of Pancreatic Cancer: Interobserver Agreement
Joo I et al.
Radiology 2019; 00:1–7 • https://doi.org/10.1148/radiol.2019190422 - Summary: Considerable interobserver variability exists in the assignment at CT of local resectability of pancreatic cancer, even among experienced radiologists.
Preoperative CT Classification of the Resectability of Pancreatic Cancer: Interobserver Agreement
Joo I et al.
Radiology 2019; 00:1–7 • https://doi.org/10.1148/radiol.2019190422 - “In the interpretation of tumor-vascular relationships, our study showed only fair agreements between reviewers. Difficulties in differentiating abutment from encasement or tumors from inflammatory changes, or in determining reconstructible invasion at CT may have caused this interobserver variability. To enhance the objectivity of tumor abutment or encasement of tortuous or fine peripancreatic vessels, three-dimensional images reconstructed from thin-section CT data, such as maximal intensity projection images and multiplanar reconstruction images perpendicular to the vessels, can be helpful.”
Preoperative CT Classification of the Resectability of Pancreatic Cancer: Interobserver Agreement
Joo I et al.
Radiology 2019; 00:1–7 • https://doi.org/10.1148/radiol.2019190422 - “Pancreatic cancer itself, by obstructing the pancreatic duct, or related invasive procedures such as endoscopic US-guided biopsy or endoscopic retrograde cholangiopancreatography can cause acute pancreatitis, usually manifesting as peripancreatic fat infiltration at imaging, thereby mimicking tumor infiltration. Because extra-pancreatic perineural tumor invasion is typically seen as soft tissue infiltration around peripancreatic vessels extending from intrapancreatic tumors, it can be difficult to differentiate it from pancreatitis-related changes.”
Preoperative CT Classification of the Resectability of Pancreatic Cancer: Interobserver Agreement
Joo I et al.
Radiology 2019; 00:1–7 • https://doi.org/10.1148/radiol.2019190422 - “In conclusion, considerable interobserver variability exists in the CT assignment of the local resectability of pancreatic cancer, even among experienced radiologists, raising concerns of reliable patient classification necessary for the appropriate selection of candidates for up-front operation or neoadjuvant treatment. Our results thus support the need for a central imaging review system to ensure consistency in the treatment allocation of patients with pancreatic cancer, particularly during prospective enrollment and in multicenter trials. Moreover, further study is warranted to obtain more refined imaging criteria or CT protocols that may further help improve interobserver agreement.”
Preoperative CT Classification of the Resectability of Pancreatic Cancer: Interobserver Agreement
Joo I et al.
Radiology 2019; 00:1–7 • https://doi.org/10.1148/radiol.2019190422 - “Pancreatic ductal adenocarcinoma can be a difficult imaging diagnosis early in its course given its subtle imaging findings such as focal pancreatic duct dilatation, abrupt duct cut-off, and encasement of vasculature. A variety of pancreatitidies have imaging findings that mimic pancreatic ductal adenocarcinoma and lead to mass formation making diagnosis even more difficult on imaging alone. These conditions include acute focal pancreatitis, chronic pancreatitis, autoimmune pancreatitis, and paraduodenal (“groove”) pancreatitis.”
Inflammatory mimickers of pancreatic adenocarcinoma
Kunal Kothar ET AL.
Abdominal Radiology (In Press, 2019) https://doi.org/10.1007/s00261-019-02233-7 - “However, PDA may be an underlying cause in a minority of patients, especially in older patients or patients who do not have risk fac- tors for pancreatitis. Signs of an underlying PDA include focal pancreatic ductal dilatation, abrupt main pancreatic duct cut-off, and encasement of vasculature. Associated findings of malignancy such as lymphadenopathy or metastases can be more definitive.”
Inflammatory mimickers of pancreatic adenocarcinoma
Kunal Kothar ET AL.
Abdominal Radiology (In Press, 2019) https://doi.org/10.1007/s00261-019-02233-7 - “Patients with chronic pancreatitis develop PDA at a greater rate than the general population and the underly- ing cancer can be difficult to diagnosis. PDA demonstrates similar imaging findings as focal or mass-forming chronic pancreatitis of CT hypodensity, T1-weighted MR hypointensity, and hypoenhancement on arterial phase contrast-enhanced imaging and progressive delayed enhancement.”
Inflammatory mimickers of pancreatic adenocarcinoma
Kunal Kothar ET AL.
Abdominal Radiology (In Press, 2019) https://doi.org/10.1007/s00261-019-02233-7 - “Findings that help favor focal or mass-like chronic pancreatitis over PDA include irregularity of the pancreatic duct, intraductal or parenchymal calcification, diffuse pancreatic involvement, and normal or smoothly stenotic pancreatic duct penetrating through the mass (“duct penetrating sign”). A duct-penetrating sign has been found in a significantly higher number of patients with inflammatory pancreatic masses versus pancreatic cancer.”
Inflammatory mimickers of pancreatic adenocarcinoma
Kunal Kothar ET AL.
Abdominal Radiology (In Press, 2019) https://doi.org/10.1007/s00261-019-02233-7
- “In addition, a considerable proportion of false positive pancreatic masses identified in the original CT report can be attributed to unrecognized autoimmune or groove pancreatitis. The knowledge on autoimmune and groove pancreatitis has rapidly increased over the past few years.”
Diagnostic value of a pancreatic mass on computed tomography in patients undergoing pancreatoduodenectomy for presumed pancreatic cancer. Gerritsen A et al. Surgery. 2015 Jul;158(1):173-82 - “In conclusion, this study confirms that the presence of a pancreatic mass on CT has a high specificity and PPV for malignancy, especially in symptomatic patients with jaundice and weight loss. However, the absence of a pancreatic mass does not rule out malignancy. Expert reassessment, especially in consensus using a uniform definition, leads to a lower, but more accurate detection rate of pancreatic masses on CT as compared with the original assessment.”
Diagnostic value of a pancreatic mass on computed tomography in patients undergoing pancreatoduodenectomy for presumed pancreatic cancer. Gerritsen A et al. Surgery. 2015 Jul;158(1):173-82 - CT of the Pancreas: Mistakes in Diagnosis
False Positive studies
• Autoimmune pancreatitis
• Groove pancreatitis
• Chronic pancreatitis
• Focal steatosis in the gland (usually HOP)
• Stent in place in CBD - CT of the Pancreas: Mistakes in Diagnosis
False Negative studies
• Small pancreatic mass
• Absence of secondary signs like dilated PD or CBD
• Acute pancreatitis or chronic pancreatitis masks underlying tumor
• Poor scan protocol
- “In all, 4 different patterns of fatty infiltration of pancreas have been described, of which focal fatty infiltration or sparing of the head and/or uncinate process of the pancreas is the common entity mimicking a pancreatic mass. On contrast-enhanced CT, the area of fatty infiltration appears hypodense to pancreatic parenchyma, mimicking a mass. However, the lack of biliary and pancreatic ductal obstruction or mass effect on adjacent vessels, maintained lobu- lated pancreatic contour, and typical distribution with sparing of peribiliary region can suggest the correct diagnosis of fatty infiltration.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Alteration of pancreatic contour with anterior or lateral extension of pancreatic parenchyma from the head of the pancreas or a lobulated appearance of tail can give the appearance of a pseudomass of the pancreas. Enhancement of the lobulated “masslike” area, being similar to the rest of pancreatic parenchyma; review of images in coronal and sagittal planes showing the lobulated outline of the pancreatic parenchyma; and lack of effacement of the interdigitating fat in the same location are helpful in avoiding this misdiagnosis.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Accessory splenic tissue within pancreatic parenchyma is seen within 3 cm from the distal end of the pancreatic tail and can mimic a solid pancreatic neoplasm. Because of its well-defined margin and homogenous enhancement on portal venous phase, intrapancreatic accessory spleen (IPAS) can be misdiagnosed as a neuroendocrine tumor of the pancreas.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Uncommon variants of pancreatitis such as autoimmune pancreatitis (AIP), focal or groove pancreatitis, and mass-forming chronic pancreatitis can mimic pancreatic adenocarcinoma, leading in some cases to unwarranted surgery to exclude underlying malignancy.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Radiological features that could suggest a diagnosis of groove pancreatitis include circumferential duodenal wall thickening with cystic changes in the wall of the duodenum and smooth narrowing of the pancreatic duct and the common bile duct, whereas abrupt duct cutoff and presence of vascular invasion would suggest a diagnosis of pancreatic adenocarcinoma.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Groove pancreatitis or paraduodenal pancreatitis is a form of focal chronic pancreatitis involving the potential space between the duodenum, head of the pancreas, and the common bile duct. Inflammatory changes and fibrosis can be seen involving only the groove region (pure form) or the pancreatic head, with extension into the pancreaticoduodenal groove (segmental form). Groove pancreatitis can mimic pancreatic adenocarcinoma involving the head of the pancreas, as both the entities show significant overlap in presentation and imaging findings and both are relatively hypovascular and show delayed enhancement on contrast-enhanced CT.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “The possibility of pancreatic carcinoma developing in the setting of chronic pancreatitis makes it important to try to distinguish between the 2 entities. Although radiological features such as smooth narrowing of the pancreatic duct or normal pancreatic duct and absence of peripancreatic vascular involvement favor a diagnosis of chronic pancreatitis, an EUS and biopsy are usually needed to exclude pancreatic ductal adenocarcinoma.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Approximately 5%-10% of PNETs can undergo cystic degeneration and mimic a true cystic pancreatic lesion. However, cystic PNETs have a thick enhancing rim along the periphery, representing a portion of the tumor that has not undergone cystic degeneration, enabling its differentiation from other cystic pancreatic lesions. A pancreatic adenocarcinoma with large areas of necrosis or a solid pseudopapillary neoplasm of the pancreas with areas of hemorrhage and necrosis can be mistaken for a heterogeneous cystic pancreatic neoplasm.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Approximately 10% of PDAs can appear isoattenuating to the adjacent pancreatic parenchyma on multidetector CT during both the pancreatic parenchymal and the portal venous phases, making it difficult to identify the tumor on imaging. Presence of other indirect signs of PDA, such as upstream pancreatic (“interrupted pancreatic duct”) or biliary ductal dilation with or without parenchymal atrophy would suggest the possibility of an underlying mass, even though one may not be seen.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - “Primary bowel masses arising from the stomach, duodenum, or jejunum that have an exophytic component can mimic pancreatic masses. An exophytic gastrointestinal tumor arising from the duodenum can mimic a pancreatic neuroendocrine tumor, considering the heterogeneous enhancement and well-circumscribed nature of both these tumors. A fluid-filled or collapsed duodenal diverticulum could mimic a hypodense pancreatic mass. Ensuring adequate bowel distension while imaging and multiplanar image review would be helpful in making the correct diagnosis.”
Pitfalls in pancreatic imaging Kaza RK et al. Semin Roentgenol. 2015 Oct;50(4):320-7 - Peripancreatic Lesions Mimicking Pancreatic Lesions
• Aneurysms or pseudoaneuryms
• Small bowel tumors or just normal bowel
• Adenopathy
• Retroperitoneal masses
- “MDT meetings impact upon patient assessment and management practices. However, there was little evidence indicating that MDT meetings resulted in improvements in clinical outcomes. Future research should assess the impact of MDT meetings on patient satisfaction and quality of life, as well as, rates of cross-referral between disciplines.”
The impact of multidisciplinary team meetings on patient assessment, management and outcomes in oncology settings: A systematic review of the literature Pillay B et al. Cancer Treatment Reviews (in press) - “Conducting regular multidisciplinary team (MDT) meetings requires significant investment of time and finances. It is thus important to assess the empirical benefits of such practice. A systematic review was conducted to evaluate the literature regarding the impact of MDT meetings on patient assessment, management and outcomes in oncology settings.”
The impact of multidisciplinary team meetings on patient assessment, management and outcomes in oncology settings: A systematic review of the literature Pillay B et al. Cancer Treatment Reviews (in press)
- “Forty-eight (40%) structured and 72 (60%) nonstructured multiphasic CT reports were reviewed. Nonstructured reports contained a mean ± standard deviation of 7.3 key features ± 2.1 (range, 1-11) and structured reports contained 10.6 ± 0.9 (range, 9-12) features (P < .001). Information for surgical planning was deemed easily accessible in 94%, 60%, and 98% of structured and 47%, 54%, and 32% of nonstructured reports by the three surgeons, respectively (P < .001, .79, < .001). Surgeons had sufficient information for surgical planning in 96%, 69%, and 98% of structured and 31%, 43%, and 25% of nonstructured reports (P < .001, .009, and < .001).”
Structured Reporting of Multiphasic CT for Pancreatic Cancer: Potential Effect on Staging and Surgical Planning.
Brook OR et al
Radiology. 2015 Feb;274(2):464-72 - “Forty-eight (40%) structured and 72 (60%) nonstructured multiphasic CT reports were reviewed. Nonstructured reports contained a mean ± standard deviation of 7.3 key features ± 2.1 (range, 1-11) and structured reports contained 10.6 ± 0.9 (range, 9-12) features (P < .001). Information for surgical planning was deemed easily accessible in 94%, 60%, and 98% of structured and 47%, 54%, and 32% of nonstructured reports by the three surgeons, respectively (P < .001, .79, < .001).”
Structured Reporting of Multiphasic CT for Pancreatic Cancer: Potential Effect on Staging and Surgical Planning.
Brook OR et al
Radiology. 2015 Feb;274(2):464-72
- “Errors in oncologic CT can be reduced by means of standardized imaging protocols that use intravenous and oral contrast material. Attention should be paid to optimal imaging techniques. Images should be analyzed systematically, with different window settings, and particular attention should be paid to known problem areas and pitfalls according to the underlying disease.”
Missed Lesions at Abdominal Oncologic CT: Lessons Learned from Quality Assurance
Siewert B et al.
May 2008 RadioGraphics, 28, 623-638. - “Advancements in MDCT technology and improvements in 3D software have significantly improved our ability to detect and characterize pancreatic pathologic disorders. However, we consistently see avoidable errors made by interpreting CT radiologists. These include failure to identify a mass, misdiagnosis of extrapancreatic structures as pancreatic neoplasms, and mischaracterization of a lesion as malignant when it is in fact benign.”
MDCT of the Abdomen: Common Misdiagnosis at a Busy Academic Center
Horton KM, Johnson PT, Fishman EK
AJR 2010;194:660-667s - “All suspected pancreatic lesions should be evaluated using thin collimation arterial and portal venous phase acquisitions, and interpretation requires review with interactive multiplanar reconstruction and 3D rendering, even if no lesion is detected on the axial scans. The 3D imaging is especially useful in distinguishing pancreatic from peripancreatic structures and for detecting subtle lesions, as well as for accurate staging of vascular encasement.”
MDCT of the Abdomen: Common Misdiagnosis at a Busy Academic Center
Horton KM, Johnson PT, Fishman EK
AJR 2010;194:660-667s