腺領域からみた胃癌の診断

Diagnosis of Gastric Cancer from the Viewpoints of Background Mucosa

要旨　1987年4月から1997年3月までに切除された胃癌症例を対象にして，癌組織型と背景粘膜およびF境界線との関係について検討した．胃癌の組織型は分化型癌541病変，未分化型癌277病変であった．未分化型癌と比べ分化型癌の症例は男性に多く，平均年齢も高く，腸上皮化生の程度も中等度～高度なものが多く従来の報告と同様であった．また胃癌とF境界線との関係を検討し以下の結果を得た．①未分化型癌で2cm以下の病変はF境界線近傍領域に多く存在した．②F境界線から離れた幽門線領域の未分化型癌は，2cm以下の病変の割合が他の領域より低く，悪性所見に乏しい発見されにくい病変の存在が考えられた．③1cm以下の分化型癌においてF境界線から2cm以内の領域に存在するものはその約2割がsm₂以深に浸潤しており，それ以外の領域に存在するものに比べ深く浸潤している傾向がみられた，④胃癌においては同じ組織型であっても，その存在する領域で形態（悪性所見）や生物学的ふるまいが異なっていた．

　The relationships among histological type of gastric cancer, background mucosa, and the F demarcation line were analyzed. There were 541 resected lesions of differentiated cancer and 277 resected lesions of undifferentiated cancer during the period between April of 1987 and March of 1997. Compared to the undifferentiated cancer, the differentiated cancer was more common in male and older, and had severer (moderate to severe) intestinal metaplasia as a background mucosa. These results were the same as previous reports. The relationships between gastric cancer and the F demarcation line were summarized as follows; 1) Undifferentiated cancers less than 2 cm in size were commonly found near the F demarcation line, 2) Undifferentiated cancers in the pyloric gland area that were apart from the F demarcation line were more commonly found larger than 2 cm in size, and those lesions may be less malignant appearance. 3) In the group of differentiated cancers less than 1 cm in size, about 20 percent of the lesions 2 cm within the F demarcation line had invasion deeper than the sm2 layer; they had a tendency to invade deeper than the lesions located in the other areas. 4) Even the same histological type of the gastric cancers, they may have different forms macroscopically and biological behavior by their location.