胃原発の濾胞性リンパ腫（follicular lymphom，nodular type）の1例

A Case of Gastric Follicular Lymphoma (Nodular type)

　Follicular lymphomaは1925年Brill¹⁾により初めて記載された．その後1944年Symmers²⁾は1つの独立疾患とみなし，Brill-Symmer's diseaseとも呼ばれていた，本疾患はリンパ細網細胞系由来の悪性腫瘍の1つであり，Rappaportら¹⁶⁾により悪性リンパ腫のnodular typeと分類されたものである．本腫瘍の胃原発例の報告は極めて少なく，散発的に認めるのみである^{4)6)～8)10)16)17)23)～25)35)36)38)}．

　今回われわれは胃に原発した本腫瘍を経験したので報告し，若干の文献的考察を試みる．

　The patient was a 42 year-old male, who had been admitted because of epigastric pain during the gastric emptying time.

　The upper GI series showed numerous irregular and shallow ulcerous lesions accompanied with converging folds in an area of about 50×30 mm at the greater curvature side of the posterior wall of the middle corpus. Although the tip of each of the folds was enlarged, there was no definite sign of tapering nor moth-eaten appearance. And the gastric wall expanded well.

　Endoscopically, the thickened mucosal folds looked like cerebral gyri, and the lesion showed multiple erosions mixed with marked nodular protuberances, but no definite margin of Ⅱc can be seen. The biopsy specimens revealed no sure sign of malignancy.

　Gastrectomy was performed. No regional lymph node swelling was noted. In the excised specimen, multiple irregular ulcers were noted in the same area as was expected before. Although the tips of the convergent mucosal folds were enlarged and confluent, they were round and Ⅱc like lesion was not obvious. In addition, the mucosal surface showed partial nodular protuberance accompanied by bridging folds suspicious of submucosal tumor. From these findings, the ulcerous type of gastric lymphoma was highly suspected.

　Histologically, the neoplastic change was observed in the submucosal area forming a submucosal ulcer (Ul-Ⅱ type of Murakami's classification). In the mucosa where proper gastric glands were destructed, there were infiltrations of mature lymphocytes. The submucosa was occupied by enlarged lymph follicles differing in size with conspicuous germinal center.

and some follicles were fused with oneanother. Lymphoid cells and reticulum cells in the follicles showed prominent pleomorphism. From these histological findings, this case was diagnosed as follicular lymphoma, nodular (“follicular”) mixed type (lymphocytic and reticulum cell) by Rappaport's classification.

　It was fortunate that neoplastic tissue was limited to the submucosa and no signs of lymph node metastasis were observed. The prognosis is expected to be favorable.