Complete Response Following Stereotactic Body Radiation Therapy with Concurrent Immunotherapy for Vaginal Melanoma

Abstract Given the rarity of vaginal melanoma (VM), sparse retrospective data guide current clinical management. Standard treatment for localized disease involves wide local excision with negative margins, but due to multifocality of disease, local invasion, and anatomic constraints, it is often difficult to achieve negative margins without more extensive surgery including potentially pelvic exenteration. Additionally, despite aggressive loco-regional multi-modality therapy with surgery and with or without adjuvant radiation therapy (RT), outcomes remain poor for VM with high rates of distant recurrence. Radiation therapy has also evolved for melanoma, suggesting higher dose per fraction may overcome relative radioresistance and promote immunogenicity. More recently immunotherapy (IO) has shown promise in treating mucosal melanoma. As a result, treatment selection for these patients can be challenging given the needs to balance the morbidity of local therapies with propensity for distant metastatic disease and overall poor outcomes. Herein, we present two cases of vaginal melanoma treated at comprehensive cancer centers managed with a multi-modality approach of stereotactic body radiation therapy (SBRT) with concurrent IO with or without surgical debulking. Local treatment was safe and effective option for these patients with vaginal melanoma and can be considered in addition to enrollment on clinical trials during multi-disciplinary discussions of care.