Melanoma of the vulva and vagina: principles of staging and their relevance to management based on a clinicopathologic analysis of 85 cases.

Abstract

Primary melanomas of the vulva and vagina are rare. As a result, it has been difficult to develop evidence-based guidelines for their management. By analyzing a large series of patients with vulval and vaginal melanomas, this study sought to document the most common presenting features, identify clinical and pathologic predictors of outcome, and provide management guidelines. A clinicopathologic analysis of 85 patients with primary melanomas of the vulva or vagina diagnosed and treated at Melanoma Institute Australia and associated units in Sydney, Australia, between 1960 and 2011 was performed. Predictors of disease-free and melanoma-specific survival (MSS) were determined. Patients with American Joint Committee on Cancer (AJCC) stage 0-II had a significantly better MSS (5Y MSS = 63.6 %, n = 59) compared with those with stage III disease (5Y MSS = 0 %, n = 12, p < 0.001). Tumor thickness, ulceration status, and pathologic clearance margin were significant predictors of MSS. Disease-free survival was predicted by these factors and additionally by tumor mitotic rate. The results of this study provide evidence to support the appropriateness of utilizing the AJCC (7th edition) cutaneous melanoma staging system for vulval and vaginal melanomas. Detection and removal of these melanomas at an early stage with pathologically confirmed clear margins confers the best chance of cure.