恶性黑色素瘤发生在肛管直肠内者颇少见,我院收治一例,曾误诊为直肠癌,现报导於下:患者女性,71岁,1973年9月18日因间断脓血便一月余入院。患者于一个多月前发现大便带脓血,不发烧,不腹痛,无里急后重,大便每日2～3次,不成形软便。近半月来肛门深处隐痛且有下坠感,排便较困难,食欲正常,既往於30年前有痢疾样病史。 Malignant melanoma occurs in the anorectal rectum is rare, one case admitted to our hospital, was misdiagnosed as rectal cancer, is now reported in the next: the patient female, 71 years old, September 18, 1973 due to intermittent pus and blood was admitted more than a month. The patient had found that the stool had sepsis more than a month ago. He had no fever, no abdominal pain, no urgency, and heaviness. The stool was 2 or 3 times a day without forming soft stools. In the past half months, the anus has deep pain and a sense of falling. It is difficult to have a bowel movement. The appetite is normal. There was a history of dysentery 30 years ago.