1399 Anorectal Melanoma: Can Be an Unexpected Diagnosis - A Case Report

Anorectal melanoma is a rare tumour. Few cases are reported in the literature. We report a case of 51 years old male complained of anal induration, itching and bloody and suppurative discharge. Patient had symptoms for 2 years. However, patient expected his symptoms are due to recurrence of haemorrhoids. Therefore, he presented late. Then, he had noticed a progressive increase in size, discharge and two opposing ulcers. Patient had no history of abdominal pain, change in bowel habits, bleeding per rectum, history of groin lumps, incontinence nor erectile dysfunction. Patient underwent haemorrhoidectomy about 11 years ago. On examination, there was a circumferential single ulcer eroding the anus extending deep to the dentate line reaching the rectum on digital rectal examination. Also, there was no inguinal lymphadenopathy detected on exam. Incisional biopsy of the ulcer showed anorectal melanoma. Patient had abdominoperineal resection (APR) with adjuvant radiotherapy. At 12 months follow up, there were no signs of recurrence.

Anorectal Melanoma - Brownish Black Mass Not Always a Hemorrhoid

The non-specific clinical symptoms of anorectal brownish-black mass do not help to differentiate colorectal cancer, hemorrhoids, rectal ulcers which result in a delayed diagnosis or lead to inadequate management of lethal anorectal melanoma. Primary malignant melanoma of the anorectal region is an uncommon tumor, constituting approximately 1% of anal canal tumors which may be misdiagnosed clinically as hemorrhoids. Because of aggressive behavior and poor prognosis, efficient and prompt diagnosis is required in these cases. We report the 2 cases of this rare tumor.