肛管是消化道末端,长度约3～4cm。在欧美肛管癌占直肠癌的1/10,近年在全世界发病率有所增加。在日本腺癌发病率高,在欧美则放射敏感性高的鳞癌发病率高。因此,在欧美国家放射治疗,特别是放射化学疗法成为肛管癌治疗的首选方法。以往认为肛管癌的标准治疗法是会阴式直肠切断术等 The anal canal is the end of the digestive tract and is approximately 3 to 4 cm in length. In the United States and Europe, anal canal cancer accounts for 1/10 of rectal cancer, and in recent years the incidence has increased worldwide. In Japan, the incidence of adenocarcinoma is high. In Europe and the United States, the incidence of squamous cell carcinoma with high radiosensitivity is high. Therefore, radiotherapy in Europe and the United States, especially radiotherapy, is the preferred method for the treatment of anal canal cancer. In the past, the standard treatment for anal canal cancer was perineal rectal surgery.