Gastric Lymphoma

• 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