CDKN2A and neoplasm: Current guidelines indicate the routine pathological evaluation of HPV in (1) newly diagnosed OSCC patients from the primary tumor or cervical nodal metastases by p16 immunohistochemistry (IHC), any additional HPV testing should be performed at the discretion of the pathologist or treating physician, and (2) patients with metastatic unknown primary from cervical upper- or mid-jugular chain lymph node by p16 IHC and then for p16+ tumors, HPV-specific detection assays must be done to confirm HPV status [11].