潰瘍性大腸炎に併発した小児胃癌の1例

Gastric Cancer Associated with Ulcerative Colitis in a Young Boy, Report of a Case

要旨　患者は14歳，男児．13歳時に難治性の潰瘍性大腸炎（UC）で全結腸切除を受けている．今回入院3か月目に噴門直下と幽門部を中心に全周性の潰瘍，胃角大彎の約1cmの山田Ⅲ型の隆起性病変をみた．生検では全域で炎症細胞浸潤が高度で，再生か腫瘍か判別しがたい異型腺管が散見された．ポリープ状病変は癌と診断され，EMR標本にて炎症細胞浸潤を伴う粘膜内の中分化管状腺癌であった．7か月目に新たに幽門部に約2cmの境界不明瞭な隆起を認め，10か月目に3～4cmの結節集簇様平坦隆起に発育した病変にEMR施行．組織所見は初回の切除病変と同様のm癌であった．本例の胃病変は組織学的にUCおよびcolitic cancerの所見と酷似した．胃を侵すUCは極めてまれであり，colitic cancerと同様の発生機序が想定される癌が胃に多発した例はこれまで報告されていない．

　The patient was a 14-year-old boy who had undergone total colectomy because of therapy-resistant ulcerative colitis at the age of 13. Gastric endoscopy performed 3 months after hospitalization revealed multiple ulcers mainly in the fundic and pyloric areas and a polypoid lesion measuring 1 cm in the greater cuvature. Histologically, it was shown that the gastric mucosa was occupied by a diffuse and massive infiltration of inflammatory cells such as neutrophils and plasma cells. Atypical glands difficult to determine as either regenerative or as neoplastic were noted diffusely and the polypoid mass was diagnosed as carcinoma. EMR specimens showed an intramucosal, moderately differentiated tubular adenocarcinoma with numerous inflammatory infiltrates. After 7 months of hospitalization, a new flat elevation 2 cm in size was found in the antrum. This lesion enlarged to a 3～4 cm granular flat lesion after 10 months of hospitalization and was resected endoscopically. Histologically the lesion was the same as the first polypoid cancer.

　Histological findings of the gastric lesions in this case were consistent with those found in ulcerative colitis and colitic cancer. Gastric involvement of ulcerative colitis has been thought to be extremely rare and multiple gastric carcinomas similar to colitic cancer has never been reported until now.