イヌの実験胃癌からみた未分化型癌(印環細胞癌)の組織発生

Histogenesis of Undifferentiated Carcinoma Observed in Experimentally Induced Gastric Cancer in Dogs

要旨　イヌの大腸に実験大腸癌を作製すべく，ENNG含有坐剤を経肛門的に連投し，進行直腸癌のほかに，2頭のイヌに多発微小胃癌を認めた．この胃の詳細な組織学的検索により，印環細胞癌が腺頸部の単一腺管内に存在することを示唆する所見を得，2層構造，萎縮を伴わず，直接腺管から押し出されるようにして内腔および粘膜固有層に拡がる像を見つけることができた．この像は印環細胞癌の発生点および粘膜固有層へ浸潤する，今までに認められていないごく初期の像と思われ，その組織発生，増殖を論じるうえで非常に興味深い所見と考える．

　To induce colorectal cancer, suppositories containing 50mg of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) were consecutively administered to dogs intrarectally. As a result, advanced colorectal cancer and minimal multiple undifferentiated carcinomas in the stomach developed in two mongrels. Their whole stomachs were sectioned serially in the width of 6μm, stained with H・E, PAS-Alcian blue and Pentachrome, and investigated on histogenesis of undifferentiated carcinoma. This investigation showed that many minimal signet-ring cell carcinomas occurred at the fundic gland, especially around the glandular neck and that cancer fell directly from the glandular lumen to the propria mucosae. But there was no atrophy of ordinary gland, and the so-called “double-layer structure”could not be detected (Figs. 4-10)． These findings may be very interesting ones for the study of histogenesis of human undifferentiated carcinomas．