Mucosal melanoma of the female genital tract: Operation modalities.

Abstract

e21060 Background: Primary melanomas originating from the female genital tract are rare and aggressive. There are still no established guidelines for its primary surgery , so we analyzed the effect of the surgical approach on its relapse free survival (RFS) and overall survival (OS ) based on a phase 3 randomized trial (NCT03435302). Methods: Mucosal melanoma patients with female genital tract primary which were stageⅠ-Ⅲ and completely resected were enrolled as part of the multicenter, randomized, controlled, phase 3 trial for the comparison of adjuvant chemotherapy (TMZ plus DDP 6 cycles) vs. High-dose interferon group (HDI, 1 year).The RFS and OS was compared between local and extensive excision group. Results: Seventy eight female genital tract primary melanoma patients were enrolled from Feb 2014 to Jun 2016, Surgical approach was chosen by the surgeon, 39.2% (29/74) took local excision and 60.8% (45/74) extensive excision. The average age was 52.3 years. Of all these patients 46.2% were vulvar primary, 53.8% vaginal, and 85.3%stage I/II, 14.7% stage III. Primary ulceration was found in 68.1% lesions, 7 cases harbored with BRAF mutation. 57.7% patients randomized to adjuvant chemotherapy and 42.3% in HDI group. All these factors showed no difference in local excision and extensive excision group. At a median follow-up of 31.2 months (range: 5.3-60.0m), 64.4% got metastases and 23.1% showed local recurrence. RFS (8.0m vs. 11.4m, p = 0.523) and local recurrence rate (13.8% vs.31.1%, p = 0.105 ) did not show significant difference between local excision group and extensive excision group. OS in whole cohort was 28.9 months, it also did not show significant difference between two groups(local 25.5m vs. extensive 40.1m, p = 0.653). In univariate analysis there was also no relation between surgical approach and OS in this cohort. Conclusions: Based on this trial, for resectable female genital tract primary mucosal melanoma, there was no difference of local control rate, RFS and OS between local excision and extensive excision group. Local excision might be adequate for the primary leision. Still more prospective data are needed for this subtype of melanoma. Clinical trial information: NCT03435302.