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Learning Modules ❯ Cardiac

Adenocarcinoma Stomach with Ulcer Invades TOP

Krukenberg Tumor from Gastric Primary

“Not all ovarian metastases are Krukenberg tumors. Krukenberg tumors are the most common subtype of ovarian metastases, and they are histologically characterized by signet ring cell mucinous features. Common primary tumor sites include the stomach or colon. Although often difficult, distinguishing between Krukenberg tumors and primary ovarian malignancy on imaging is important because of management and prognostic implications.”
Krukenberg Tumors: Update on Imaging and Clinical Features
Maria Zulfiqar et al.
AJR 2020; 215:1020–1029

”Approximately 10% of ovarian tu- mors are metastatic masses, almost 50% of which are Krukenberg tumors. Nearly 80% of Krukenberg tumors are bilateral. The estimated incidence of Krukenberg tumors is approximately 0.16 tumors per 100,000 population per year.”
Krukenberg Tumors: Update on Imaging and Clinical Features
Maria Zulfiqar et al.
AJR 2020; 215:1020–1029

”The survival of patients with Krukenberg tumors is very poor (usually less than 2 years) and seems to be associated with the primary tumor site. Frequently, the detection of Krukenberg tumors precedes the diagnosis of the primary tumor, which may be small and asymptomatic and which rarely may even remain undetected for several years after oophorectomy, further complicating the initial diagnosis.”
Krukenberg Tumors: Update on Imaging and Clinical Features
Maria Zulfiqar et al.
AJR 2020; 215:1020–1029

CT Imaging of Gastric Cancer: Pitfalls

Small flat wall lesions can be missed
Accurate definition of depth of invasion may be difficult
Detection of early nodal involvement especially in the celiac nodal chain

Gastric Adenocarcinoma with Perforation

Perforated Gastric Ulcer

Gastric Adenocarcinoma: Differential Dx

Lymphoma
GIST Tumor
Metastases
Gastritis
H pylori infection

Gastric Lymphoma

Most frequent GI site of malignant lymphoma (50% of all GI lymphomas)
1-5% of gastric malignancies
Most are Non-Hodgkin
- Gastric Hodgkin disease accounts for 9% of all gastric lymphomas
- Primary gastric Hodgkin disease is extremely rare

“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.

Gastric Lymphoma: CT Patterns of Involvement

Polypoidal mass
Diffuse or focal infiltration
Ulcerative lesion
Mucosal nodularity

Gastric Lymphoma: CT Findings

Radiographic appearance often reflects the gross pathologic findings

Infiltrating form
- Wall thickening(with little enhancement)
- average 4-5 cm ( now picking up earlier)
- diffuse or segmental
- May be difficult to differentiate from scirrhous carcinoma
Polypoid mass
Adenopathy

CT Findings

Lymphoma vs Adenocarcinoma

CT findings can overlap
Lymphoma
- Adenopathy can extend below the renal hilum without perigastric adenopathy
- Can extend into duodenum
- Nodes usually larger in lymphoma
- Perigastric fat plane more likely to be preserved.

MALT Lymphoma: Facts

MALT lymphoma or mucosa associated lymphoid tissue is a low grade lymphoma
Associated with H. pylori infection
Most frequent CT finding is wall thickening which is often minimal
May look similar to gastric adenocarcinoma

B-Cell Lymphoma Stomach as Incidental Finding (suspect adenoca stomach)

Gastric Lymphoma Presented as GI Bleed

B Cell Gastric Lymphoma with Ulcers (Original Path neg)

GIST (Gastrointestinal Stromal Tumors): Facts

60-70% of GIST tumors occur in the stomach
20-30% of GIST tumors arise in the small bowel
They may also occur in the esophagus and colon

GIST (Gastrointestinal Stromal Tumors): Facts

Arise from common precursor cell
Display spindle cell or epithelioid morphologic characteristics
Immunohistochemical markers
- C-kit (CD117) protein (key for dx)
- CD34 protein
- S-100 and desmin (less common)

Gastric GIST Tumors

2.5% of all gastric tumors
10-30% are malignant
Malignant risk increases with
- Extragastric location
- Size > 5cm
- Extension into adjacent organs
- > 1 mitosis per 50 high powered field

Gastric GIST Tumors: CT Findings

Exogastric mass
Ulcerations very common in malignant GIST’s
Malignant GIST’s are often inhomogeneous with central necrosis
Metastases to liver is most common site of metastases