RecruitingPhase 2Drug trialAdjuvant Immunotherapy After Salvage Surgery in Head and Neck Squamous Cell CarcinomaTwo randomized trials of reirradiation after salvage surgery have been conducted by the GETTEC and GORTEC collaborative groups, both members of the French HN Intergroup: The first trial compared reirradiation and a "wait and see attitude" and was published in 2008 \[1\]. The second trial compared two modalities of reirradiation. Our hypothesis is that adjuvant treatment with immunotherapy will lead to a DFS similar to that observed in previous trials of post-operative reirradiation with possibly lower toxicity.