Management of human papillomavirus-related unknown primaries of the head and neck with a transoral surgical approach.

BACKGROUND Amidst a rising incidence of p16-positive (p16+) oropharyngeal cancer, a significant number of cases present as regionally metastatic disease with an "unknown" primary. Preliminary data support transoral surgery as an effective method of primary detection/treatment. METHODS An observational cohort study of 65 p16+ unknown primary patients treated with transoral surgery and neck dissection (2001-2012) was performed. Adjuvant therapy and recurrence data were collected. Kaplan-Meier estimates were computed for disease-specific survival (DSS) and overall survival (OS). RESULTS The primary detection rate was 89% (58 of 65). Five-year DSS and OS were 98% and 97% for the detected group and 100% for the undetected, respectively. Seventeen patients were treated with surgery alone. Of the 47 patients receiving adjuvant therapy, radiation to the pharynx was spared in 36. CONCLUSION The transoral approach was highly effective for the diagnosis and treatment of the p16+ unknown primary and laid the foundation for deescalated radiation by elimination of the pharyngeal field.