To assess the predictive role of identified immunotypes on immunotherapy treatment, the authors analyzed two cohorts: 32 HNSCC treated PD-L1 inhibitors with anti-PDL1 durvalumab and 35 HNSCC patients (HNSCC-Nivo cohort) receiving first-line anti-PD-1 nivolumab alone or nivolumab in combination with the indolamine-2,3-dioxygenase-1 inhibitor BMS-986205 (IDOi). This evidence concerns the gene CD274 and head and neck squamous cell carcinoma.