同時性多発大腸癌の臨床病理学的特徴と分子生物学的特徴

Clinicopathologic and Molecular Biologic Features of Synchronous Multiple Colorectal Carcinomas

要旨　同時性多発癌66症例の臨床病理学的特徴を，単発大腸癌（進行癌83症例，早期癌195症例）と比較した．多発癌では，年齢には差はなかったが，性差では男性に多かった．発生部位は，多発癌は左側優位であり左側同側発生が最も多かった．組織学的には多発癌での腺腫の共存（腺腫内癌）の頻度が高く，その組織発生におけるadenoma-carcinoma sequenceの関与の重要性が示唆された．また，p53遺伝子異常による解析により，すべての症例で同一症例内の個々の病変のp53遺伝子は変異の有無あるいは変異の存在部位が異なっており，大腸における多発癌は多中心性発生が主体であると考えられた．

　Clinicopathologic features of 66 cases of synchronous multiple colorectal carcinomas were evaluated by comparison with solitary ones (83 cases of advanced carcinomas and 195 cases of early ones). In cases of multiple carcinomas, males were affected more often than females. The tumors were predominantly located on the left side of the large bowel. Histologically, incidence of co-existing adenoma was significantly higher in cases of multiple tumors than in cases of solitary ones. The results suggested a significance of adenoma-carcinoma sequence in their carcinogenesis.

　In addition, discordance of the mutation pattern of p53 in individual lesions of multiple synchronous colorectal carcinomas supported the suspicion of their multicentric origin.