肛門管早期癌

Early Carcinoma of the Anal Canal

要旨　1984年から2002年の間に原口外科ならびに鹿児島大学第1外科において手術の行われた肛門管早期癌13例と下部直腸早期癌19例を対象に，両者を臨床病理学的に対比して，肛門管早期癌の症状，診断につき検討した．肛門管早期癌の有症状例は，下部直腸早期癌に比べ，m癌において有意に多かった．主訴は出血が13例中8例で最も多く，直腸指診で触知不能の癌がm癌9例中6例にみられた．しかし，sm癌はすべて触知可能であった．13例中9例は肛門鏡を用い，4例は内視鏡で発見された．下部消化管の内視鏡診断が飛躍的進歩を遂げた今日でも，肛門管早期癌の発見例は少ない．肛門管早期癌の診断には，肛門鏡に限らず内視鏡検査においても肛門出血を重視し，特にm癌では触知不能の癌もあることを念頭に，肛門管の入念な観察と積極的な生検が必要である．

　Early carcinoma of the anal canal (ECA) is rare. We examined the clinicopathlogical characteristics of 13 ECA patients. Anal bleeding was observed in about two third of these ECA patients, and there were only two asymptomatic patients. About one third of ECA cases were not palpable with digital examination. These were all intramucosal carcinoma and smaller than 15mm in diameter. All submucosal carcinomas of the anal canal were palpable with digital examination. Statistically, patients with intramucosal anal canal carcinoma had symptoms more frequently than patients with intramucosal cancer of the lower rectum. The frequency of early carcinoma in the anal canal was less than that in the lower rectum. A careful observation and trial biopsy combined with anoscopy and colonoscopy, and careful digital examination are needed in order to find ECA.