Human papillomavirus and head and neck cancer.

An increasing subset of patients with head and neck squamous cell carcinoma (HNSCCA) is positive for high-risk human papillomavirus (HR-HPV). Patients tend to be younger, have a minimal or absent tobacco and ethanol abuse history, increased number of lifetime sexual partners (particularly oral-genital sex), and squamous cell carcinomas (SCCAs) arising in the oropharynx. The most common HR-HPV associated with HNSCCA is HPV-16. HR-HPV positivity is associated with decreased expression of the p53 and Rb genes, overexpression of p16, decreased expression of EGFR, and a different genetic expression pattern compared with patients with HR-HPV-negative SCCAs, leading to the conclusion that this is a distinct clinical entity. Patients who have HR-HPV-positive HNSCCAs have an improved prognosis, particularly those with oropharyngeal SCCAs, leading some to speculate that the intensity of treatment might be decreased. At present, whether this can be done safely remains unclear.