肛門管悪性腫瘍の臨床的特徴と治療方針

Rare Malignant Tumors of the Large Intestine. Clinical Features and Treatment Strategies of Anal Canal Malignant Tumors

要旨●肛門管悪性腫瘍の臨床的特徴と治療方針について述べる．本邦では最も多いのは腺癌，粘液癌であり，続いて扁平上皮癌，痔瘻癌の順であった．腺癌の治療は下部直腸癌の治療方針に則って，リンパ節郭清を含めた手術が行われ，術前に化学放射線療法が選択されることもある．扁平上皮癌は通常の鉗子生検で診断され，治療は化学放射線療法が増えている．痔瘻癌は痔瘻からコロイド状の流出がみられた場合は要注意であり，積極的に麻酔下に瘻孔部の掻爬を行い，病理検査に提出する．悪性黒色腫は進展が早く，手術をしても予後不良である．乳房外Paget病とpagetoid spreadは治療と予後が異なる．

　We report clinical features and treatment strategies of anal canal malignant tumors. In Japan, the number of patients with adenocarcinoma and/or mucinous carcinoma is the highest, SCC（squamous cell carcinoma）is second, and anal fistula cancer is third. According to the treatment strategy of rectal cancer, surgical lymph node dissection is generally performed for adenocarcinoma of the anal canal, and preoperative CRT（chemoradiotherapy）might be chosen. Forceps biopsy is useful for the diagnosis of SCC, and CRT is increasingly used for its treatment. When colloidal discharge from the anal fistula is observed, curettage of the anal fistula under anesthesia and pathological examination of the samples are highly recommended. Malignant melanoma is extremely aggressive and shows poor prognosis even after surgical treatment. Treatment and prognosis of perianal Paget's disease are different from those of Pagetoid spread.