A large retrospective multicenter study of vaginal melanomas: implications for new management

The outcome of patients presenting with vaginal melanoma has been assessed in a large multicentric retrospective study. The databases of 12 French institutions were searched for primary vaginal melanomas managed between 1990 and 2007. Among the 54 patients recorded, 46 were managed with a curative intent and included in the study. The clinical characteristics, treatments, and detection of c-KIT protein expression have been studied. The median age of the patients was 63.5 years (42-88). Twenty-eight patients were classified as International Federation of Gynecology and Obstetrics (FIGO) stage I, five as stage II, six as stage III, and one as stage IVA. c-KIT protein was overexpressed in 80% of the patients. Forty-two patients underwent surgical resection of the tumor, nine patients received local adjuvant treatment, and 10 received systemic adjuvant therapy. The median relapse-free survival was 10.9 months. c-KIT-negative status (P=0.01) and stage I (P=0.02) were associated with locoregional recurrence. The rate of metastasis was increased for advanced FIGO stages (P<0.01). The median overall survival (OS) was 28.4 months. The finding of lymph node metastasis adversely affected OS (P<0.01). Conservative surgery and radiotherapy were associated with a decrease in metastasis-free and OS (P<0.01) compared with surgery alone, this group of patients presenting with advanced FIGO stages (P=0.02). Despite the use of limited data, conservative surgery combined with a sentinel lymph node procedure, followed by adjuvant radiotherapy could be proposed to patients with early FIGO stage in the absence of validated management. c-KIT negativity by immunochemistry appears to be a poor prognosis marker in terms of locoregional recurrences but not for metastatic spread nor survival. Further assessment of the role of c-KIT expression in this disease is thus mandatory to select patients for targeted therapy.