肝，脾，肺，リンパ節への広範な遠隔転移を来した実験イヌ胃癌の1症例

Experimental Canine Gastric Carcinoma with Metastases to the Liver, Spleen, Lungs and Lymph Nodes

　杉村ら¹⁾のニトロソグアニジン経口投与によるラット胃癌の作製以来，実験動物を用いた胃癌の研究が広く行われるようになった．しかし，現在までにヒト臨床例に類似した広範な転移を来す実験胃癌は比較的まれであった．今回，われわれはN-ethyl-N'-nitro-N-nitrosoguanidine（ENNG）投与による実験イヌ胃癌で，肝，脾，肺，リンパ節に広範な転移を来し，短期間で腫瘍死した1例を経験したので報告する．

　われわれは実験イヌ胃癌の系において，免疫療法剤の効果判定に関するモデル作製のための基礎的検討を行っており，本症例はそのうちの1頭である．

　Little observation was hitherto made on metastases to the lungs and spleen in experimental canine gastric carcinoma. This is a case report of nitrosoguanidine induced canine gastric carcinoma with metastases to the liver, spleen, lungs and lymph nodes.

　Male beagle, 16 months old, weighing 10.3kg, was given 500ml of 50μg/ml N-ethyl-N'-nitro-N-nitrosoguanidine solution per day for eight months. On the 183th experimental day endoscopic study showed erosions from the gastric angle to the antrum and its biopsy specimen revealed adenocarcinoma. The carcinoma gradually developed endoscopically and emaciation was remarkable. On the 397th experimental day the beagle died and autopsy showed 5.5×3.5cm Borrmann's type 3 advanced cancer in the gastric antrum. Histologically this lesion consisted of well differentiated adenocarcinoma, poorly differentiated adenocarcinoma and signet ring cell carcinoma. Metastases to the liver, spleen, lungs and lymph nodes were also observed and they were adenocarcinoma histologically.