Overview Trial Combining Pembrolizumab and Cesium 131 Brachytherapy With Salvage Surgery in HNSCC Status: Recruiting Trial end date: 2025-02-04 Target enrollment: Participant gender: Summary To Study Perioperative PD-1 Inhibitor and Cesium-131 Interstitial Brachytherapy in patients with locally recurrent HNSCC eligible for salvage surgery. Phase: Phase 1/Phase 2 Details Lead Sponsor: University of CincinnatiCollaborator: IsoRay Medical, Inc.Treatments: Pembrolizumab