1996 年 36 巻 5-6 号 p. 363-368
A 65-year-old woman was admitted to our hospital because of gastric tumor which was detected with gastric endoscopy during examination for hematemisis. She was symptom free and physical examination revealed no remarkable change. Gastric endoscopy in our hospital revealed a flat lesion in the middle body of the stomach. Biopsy specimen showed slight lymphoid infiltration. Subtotal gastrectomy was performed on December 24th, 1991. Examination of tissue specimens revealed atypical lymphoid infiltration surrounding the follicles (fig. 1) and involvement of the regional lymph nodes. Lymphoid cells were small to medium sized cells with slight nuclear irregularity (fig. 2). Immunohistochemical study on frozen section demonstrated that neoplastic cells were CD20+, sk-, sl+, slgM+, slgD+, CD5-, CD10-(tab. 1). Ig H gene rearrangement was confirmed with Southern blotting. COP therapy was done twice in February 1992, but was discontinued because of elevation of serum hepatic enzymes. She was diagnosed as drug induced hepatitis and predonisolone was administered. Follow-up biopsy specimens of the stomach and the colon revealed Infiltration of lymphoma in 1993 and in 1994, respectively. In June 1995, CBC test showed increased WBC with lymphocytosis, consistent with leukemic phase of malignant lymphoma. We reexamined the specimen of the stomach in 1991 after the patient showed leukemic change. On frozen sections neoplastic cells were negative for CD23 as in the flow cytometric study of the peripheral blood (tab. 2). Lymphoma cells of the stomach were positive for cyclin D1 with nuclear staining pattern (fig. 3). We have concluded that this case was mantle cell lymphom of the stomach without polypoid lesions.