粘膜内癌の併存した多発性胃悪性リンパ腫の1例

Multiple Malignant Lymphoma and Mucosal Adenocarcinoma Coexisting in the Stomach, Report of a Case

　胃悪性リンパ腫は，胃肉腫の約60～70％にみられ，胃に原発する非上皮性腫瘍の中でも比較的よくみられる疾患である．しかし，多発性胃悪性リンパ腫は，胃悪性リンパ腫の14～18％にみられ比較的まれな疾患である．また，胃悪性リンパ腫と腺癌の併存例は極めてまれで，現在まで6例の報告をみるにすぎないようである．私どもは，最近同一胃に多発性胃悪性リンパ腫と粘膜内癌が併存した極めてまれな症例を経験したので報告する．

　Malignant lymphoma of the stomach is a relatively rare tumor, constituting 0.5％ of all gastric malignancies in Japan. Moreover, coexisting malignant lymphoma and adenocarcinoma of the stomach is extremely rare. Review of the literature shows only six cases of both malignant lymphoma and adenocarcinoma coexisting in the stomach. Multiple malignant lymphoma is a rare tumor, constituting 14～18％ of all malignant lymphomas of the stomach. Multiple malignant lymphoma and adenocarcinoma coexisting in the stomach have not been described.

　Multiple malignant lymphoma coexisting with adenocarcinoma in the stomach of a 65-year-old man complaining of pain was studied. In the resected specimen, nine malignant lymphomas and a mucosal adenocarcinoma were found. Seven superficial spreading-type malignant lymphomas with converging mucosal folds were seen on the corpus, two mass-forming type malignant lymphomas like Borrmann 2 type carcinoma were seen on the cardia and fornix. A depressed-type mucosal carcinoma (Ⅱc), histologically well-differentiated tubular adenocarcinoma, was on the posterior wall of the antrum near the greater curvature. All lesions were independently seen in the stomach.

　It is sometimes difficult to differentiate the superficial spreading-type malignant lymphoma like the Ⅱc-type carcinoma from the depressed-type mucosal carcinoma (Ⅱc), just as this case shows. Retrospectively, in the superficial spreading-type malignant lymphoma, the margin and mucosal folds in disruption and tapering is more unclear, and its depressed area is smooth as compared with the Ⅱc-type carcinoma.