[Anorectal malignant melanoma].
The cases of four patients who are carriers of primitive anorectal malignant melanoma are presented, reviewing at the same time the medical literature available. The clinic of all these patients was similar: pain, proctorrhagia, tumors, tenesmus, hemorrhoids and changes in the intestinal rhythm. One of these cases was similar to thrombosed hemorrhoids, and for this reason we believe that all of the parts that are removed should be biopsied. The prognosis of this pathology is in general adverse, notwithstanding the treatment received. There are very few cases on record that have survived more than 5 years, with early diagnosis and treatment with an abdominal-perineal resection. Radiotherapy and chemotherapy can reduce the size of the lesion but it is acknowledged that the prognosis will not change.