As low tumoral phospho-ErbB3 levels and elevated CD8+ T-cell infiltrations are recently established events driving good patient survivals in HNSCC (Takikita et al, 2011; de Ruiter et al, 2017), our study first defined somatic MAPK pathway mutations as novel genomic events governing both important outcome-favoring features in HNSCC. Here, CD8A is linked to head and neck squamous cell carcinoma.