Optimal surgical management strategy for treatment of primary anorectal malignant melanoma-a systematic review and meta-analysis.

BACKGROUND

Primary mucosal anorectal malignant melanoma (AMM) is an invasive malignancy with poor survival. Management options have been variable, due to limited data and lack of randomised control trials available on the optimal surgical strategy. The aim of this review was to compare local excision versus radical resection.

METHODS

A systematic search of articles in PubMed, Ovid, Scopus, and the Cochrane Library database was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The outcomes of interest were the impact that surgical strategy had on survival (primary) and recurrence rates (secondary) for the treatment of AMM, comparing sphincter sparing local excision (LE) versus extensive abdominoperineal resection (APR).

RESULTS

Ten studies met the predefined criteria. Overall, there were 303 patients, with a median age of 58.2 years. Sixty-one percent (n = 187/303) had radical surgery (abdominoperineal resection) for the primary treatment of AMM. Overall, 5-year survival for the APR and LE was 23% and 32% respectively. Meta-analysis on the median OS noted no statistical difference between the two groups. However, local recurrence occurred in 20.82% and 47.04% in the APR and LE groups respectively. Meta-analysis observed a statistically significant reduction in recurrence when patients had an APR as primary treatment (OR 0.15, 95% CI = 0.08-0.28, p < 0.00001).

CONCLUSION

Though local recurrence rates are more common with local excision of AMM, this does not confer an inferior OS when comparing LE versus APR. The decision to proceed with LE vs. APR should be made on a case-by-case basis.