5年間の経過で0′-Ⅱc型M癌から3型mp癌へ進展した胃癌の1例

Type 3 Advanced Gastric Cancer Developing from Type 0′-IIc Early Gastric Cancer, Report of a Case

要旨　患者は71歳の女性．1988年11月心窩部不快感を訴え受診し，胃内視鏡検査で前庭部小彎に径約5×2mmの0′-Ⅱc型粘膜内癌を指摘され，生検でも高異型度分化型癌と診断された．その後患者との連絡がとれず，5年後の1993年11月に近医から紹介され再受診し，前庭部小彎に径19×16mmの3′型進行癌を認め胃亜全摘術が施行された．深達度はmpであった．初回生検時，本腫瘍(粘膜内癌)のKi-67 LIは26.5であったが，5年後の切除標本では更に異型度の高くなった腫瘍細胞から構成され，粘膜内腫瘍部と考えられる領域のKi-67 LIは83.7と増加していた．本例はⅡc型高異型度分化型癌が5年間に更に異型度を増しながらmp癌へと発育進展した1つのnatural historyが追えたものと考えられた．

　A 71-year-old woman was found to have a tiny depressed intramucosal carcinoma measuring 5 mm in size in the lesser curvature of the antrum. The histological examination of the biopsy specimen revealed differentiated tubular adenocarcinoma, high-grade.

　The patient didn't return to the hospital and, after that, nothing more was heared of her. Five years later, she was referred to our hospital again. The lesion was detected as an infiltrative ulcerating type advanced cancer. She agreed to our proposal to receive subtotal gastrectomy. The resected specimen showed differentiated tubular adenocarcinoma invading as far as the proper muscle layer. Ki-67 labeling index (L.I.) of the tumor in the proper mucosal layer had increased to 83.7 compared with 26.5 L.I. of the first biopsy specimen five years before. The Ki-67 L.I. represents the growth fraction of a tumor, indicating one aspect of tumor malignancy. So it is suggested that this tumor showed that cancer progression occurred during the period of five years from an intramucosal carcinoma to an advanced cancer.