Cisplatin+Pembrolizumab+RT in Vulvar Cancer

Inclusion Criteria: * Participants must have histologically or cytologically confirmed unresectable, incompletely resected, recurrent, or metastatic squamous cell carcinoma of the vulva.Patients with unresectable disease are defined as T2 or T3 primary tumors (N0-3, M0) not amenable to surgical resection by standard radical vulvectomy. * Participants must have measurable disease based on RECIST 1.1. Lesions situated in a previously irradiated area are considered measurable if progression has been demonstrated in such lesions. * Have provided archival tumor tissue sample or newly obtained core or excisional biopsy of a tumor lesion not previously irradiated. Formalin-fixed, paraffin embedded (FFPE) tissue blocks are preferred to slides. * Prior therapy: Participants with no prior therapy are eligible and patients with recurrent disease must not have had more than two lines of cytotoxic therapy. Topical or hormonal therapy are not counted towards prior lines. Prior treatment with immunotherapy is allowed, provided treatment was not stopped for grade 2 or greater adverse events. * Time from prior therapy: * Systemic anti-neoplastic therapy: 5 half-lives or 4 weeks, whichever is shorter. * Hormonal therapy is not considered anti-neoplastic therapy. * Radiotherapy: Any prior irradiation is acceptable provided the site being considered for study has not been previously irradiated. * Age ≥18 years. Because insufficient dosing or adverse event data are currently available on …