Anorectal melanoma: surgical management guidelines according to tumour thickness

Abstract

Management of patients with anorectal melanoma is still controversial. To reach a rationale therapeutic approach, we reviewed our experience obtained over the past decade. In all, 19 consecutive patients with the diagnosis of anorectal melanoma were included in this retrospective survey. Details of the patients' presentation, symptoms, tumour size and histology and tumour state were recorded, and the primary therapeutic procedures were evaluated in detail. The size of the tumours ranged between 0.5 and 7 cm in diameter. The median tumour thickness was 10 mm (range 0.6-40 mm). At diagnosis, six of 19 patients already presented with either regional or distant metastases. The remaining 13 patients were treated with curative intend, either by abdomino-perineal resection (APR) or wide local excision (WLE). The form of operative therapy, however, had no impact on overall survival. Nevertheless, the incidence of local recurrences was lower after APR even for patients with less favourable tumours. In conclusion, WLE alone is not sufficient for local tumour control of thick anorectal melanoma.

Figure 1

(A) A 57-year-old women with a polypoid anal melanoma at 3° with little pigment at the base of the polypoid tumour (arrow). (B) Low-power view of polypoid MM of the anorectal region with superficial ulceration (HE × 80). (C) Detail: Extensive tumour growth beneath intact surface squamous epithelium (HE × 250).