Which characteristics can be expected from p16+-squamous cell carcinomas of the posterior oral cavity and oropharynx? - Distinctive results from Central Germany.

PURPOSE:Human papillomaviruses (HPV) link to a subset of head and neck squamous cell carcinomas (HNSCC). Our aim was to identify clinicopathological characteristics (CPC) of squamous cell carcinomas of the posterior oral cavity and oropharynx (SCCPOCO) associated with HPV p16+. METHODS:Using a retrospective cohort study design, we enrolled a sample of SCCPOCO patients treated in a Central German hospital over a 3-year period. The predictor variables: CPCs, were grouped into demographic, social, anatomic and prognostic. The main outcome variable was p16+. Appropriate statistics were computed, and P≤0.05 was considered statistically significant. RESULTS:Of 199 HNSCC patients, 23 had SCCPOCO and entered the analysis (mean age, 67±12 years; 4 females; 16 in stage I; 4 p16+; 22 underwent primary surgery). We found 8 cervical lymph node metastases (34.8%), 3 distant metastases (13%), 9 recurrences (30.1%) and 3 overall deaths (13%). With the exception of recurrence (P=0.006) and overall death (P=0.02), p16+ was not associated with predictor variables: young age, male gender, smoking, alcohol consumption, tumor location, TNM stages, time to recurrence, metastases, death from disease and survival of smokers (P>0.05). Primary brachytherapy failed to improve survival of p16+-SCCPOCO patients (P=0.04). CONCLUSIONS:The results of this study suggest that p16+- and p16--SCCPOCOs in Central Germany share similar CPCs, except recurrence and overall death. Upfront surgery with/without radio(chemo)therapy is recommended for all operable SCCPOCOs, regardless of HPV-status. Patients with p16+-SCCPOCOs require close follow-up. Future research should investigate the cause of these distinctive CPCs.