CDKN2A and head and neck squamous cell carcinoma: We further examined if there were differences in the LSD1 expression levels between different sites of origin in primary HNSCC using tissue samples from primary tumors (n = 339) originating from the hypopharynx (n = 46), larynx (n = 98), oral cavity (n = 77), and oropharynx (n = 107, n(p16+) =56, n(p16−) =51).