Document resource
Background Mucosal melanoma is a rare and highly aggressive malignancy. Patients with locally advanced disease suffer from a high risk of distant metastasis even after extensive surgical resection, in addition to functional impairment from organ loss. We report our experience with dual immune checkpoint inhibitors (ICIs) as an organ-preserving alternative approach.Methods Consecutive patients who started dual ICIs (ipilimumab and nivolumab or relatlimab and nivolumab) as initial therapy for locally advanced mucosal melanoma at Inova Schar Cancer Institute between 2017 and 2023 were retrospectively identified. Data on clinical and molecular profiles, treatment response and toxicity were obtained and analyzed.Results Eleven patients were identified. Median age at diagnosis was 62 years (range 51–81). The primary location of melanoma included anorectum (n=4), nasal cavity (n=3), oral cavity (n=2), penis (n=1), and vagina (n=1). All were staged T3 or above, and six had nodal involvement. Seven patients received a combination of ipilimumab and nivolumab, two of whom underwent concurrent radiation therapy. 4 (57%) of the 7 patients had complete response (CR) on clinical exam or biopsy, while the other 3 had progressive disease (PD). Two developed recurrence at 1.5 and 6.3 years post-remission, one of whom achieved CR after salvage therapy with nivolumab. Among the 4 patients who were treated with relatlimab and nivolumab, 1 (25%) still on treatment showed partial response while the other 3 showed PD. One patient with PD went through salvage surgery. A total of nine patients are alive up to date. Three experienced CTCAE grade 3 adverse events (pneumonitis, transaminase elevation).Conclusions Our case series demonstrates the potential of immunotherapy to achieve disease control while preserving organ function in patients with locally advanced mucosal melanoma.