Lymphoma of the Stomach

• Comprises 3-5% of all gastric neoplasms

• Non-Hodgkin’s accounts for 80% of all gastric lymphomas

• Begins in the submucosa

• Most occur in distal body and antrum of stomach

• Almost all gastric lymphoma presents with some degree of ulceration

Frequency of GI occurrence by site (of all lymphomas)

•Stomach

•Small intestine

•Rectum

•Rest of colon

Lymphosarcoma of the Stomach

• Suggested by the relatively younger age at presentation than ca

• Suggested by the extent of the lesions radiographically—multiple ulcers, irregular masses, widespread infiltration

• May be associated with involvement of the bowel elsewhere—e.g. duodenum, cecum or rectosigmoid and mesenteric masses

Forms

• Nodular—single or multiple intragastric masses, easily confused with ca, protrude into the lumen, often with multiple ulcerations

• Polypoid—barium in interstices, frequently with ulceration; sometimes resembles metastatic disease such as melanoma

• Ulcerative—shallow, saucer-like ulcer indistinguishable from ca

• Infiltrative—thickened, irregular folds, simulating the appearance of hypertrophic gastritis; about 10% present this way

CT Staging

• Stage I tumor confined to bowel wall

• Stage II limited to local nodes

• Stage III widespread nodal disease

• Stage IV bone marrow, liver, other organs

DDX-Linitis plastica

•Carcinoma

•Lymphoma

•Gastritis, e.g. phlegmonous, eosinophilic, postradiation

•Granulomatous, e.g. Crohn’s, sarcoid, TB

•Syphilis

•Amyloidosis

WH/95