Treatment outcomes of vulvar and vaginal melanoma at an NCCN institution between 1993 and 2021

Background: Vulvar melanoma and vaginal melanoma are rare and difficult to treat. We describe the last three decades in a cohort predominantly treated surgically with adjuvant therapy. Methods: All new patients between 1993 and 2021 followed until 2024. Collection of demographic and oncologic data allowed comparisons and Kaplan-Meier method was used to evaluate overall survival (OS) and progression free survival (PFS) stratified by adjuvant therapy type, diagnosis before and after 2011, and between vulvar and vaginal melanomas. Results: Consultation for 63/72 patients (87.5 %) were for primary treatment. Most patients had vulvar melanoma (50/72, 69.4 %), received surgery (65/72, 90.3 %), and adjuvant treatment (40/72, 55.6 %) with immunotherapy, chemotherapy, and/or targeted therapy. Median survival for 63 patients presenting for primary treatment was 54.2 months, and 9/13 patients who were disease free after five years later received adjuvant immunotherapy. Survival did not vary by adjuvant therapy type or diagnosis after 2011 but was significantly less for vaginal melanoma. Following recurrence seven patients experienced complete response including three patients receiving combined nivolumab with ipilimumab and two nivolumab alone experienced. Conclusions: Survival was not significantly different by adjuvant therapy type or after 2011. Most patients who were disease-free five years after surgery had received adjuvant therapy. Seven patients experienced complete responses to therapy after recurrence of whom five received immune checkpoint inhibitors. Although survival is not improved as in cutaneous melanomas by immune checkpoint inhibitors, signal continues for the use of immune checkpoint inhibitors in gynecologic melanomas.