What is the best surgical treatment for anorectal melanoma?

This study compared outcome following the two common surgical procedures for anorectal melanoma: wide local excision and abdominal perineal resection. We also examined the utility of endoluminal ultrasound to guide therapy.

Records of 19 patients surgically treated at our institution were studied. In addition to type of surgical procedure, we noted age, metastatic disease spread, sphincter involvement, tumor size and thickness, and mode of diagnosis. Survival after diagnosis and after recurrence of disease were also recorded. Ultrasound was used in seven, with the lesion delineated in six (all had therapy guided by the ultrasound). Regarding surgery ten had wide local excision, seven had abdominal perineal resection, and two had other procedures.

The most common sites of recurrence were distant in 31.6% and regional lymph nodes in 26.3%. Mean survival after recurrence was 13 months (range 5-29). Two patients who had wide local excision are disease free and alive 135 and 29 months after diagnosis. Neither surgical treatment conferred obvious benefit on survival.

Ultrasound can guide management by delineating lesions amendable to wide local excision. Since the mortality rate is high, wide local excision offers the advantage of avoiding a permanent colostomy and should be considered the procedure of choice when excision is feasible.