| Summary points: | A 57-year-old male is admitted with a chief complaint of intermittent rectal bleeding and constipation that had started 6 months ago. Physical examination, digital examination, laboratory tests, proctosigmoidoscopy, multiple biopsies, histopathology, computed tomography, endoluminal ultrasound, abdominoperineal resection, primary treatment, and follow-up are described. The authors discuss diffuse anal canal melanoma and give reference to the current diagnostic and treatment options. |