Long-term survival and swallowing outcomes in advanced stage oropharyngeal squamous cell carcinomas.

BACKGROUND: There is a paucity of studies reporting long-term survival outcomes for HPV/p16 positive oropharyngeal squamous cell carcinoma (OPSCC). This study aims to compare long-term outcomes of advanced stage p16 positive and negative OPSCCs, treated by surgical and non-surgical modalities.

METHODS: OPSCC patients from 1998 to 2012 were identified through a prospectively collected cancer registry. P16 immunohistochemistry was used as a surrogate marker for HPV-OPSCC. Overall survival (OS) and aspiration free survival (AFS) comparisons were made between patients treated with chemoradiation (CRT) versus primary surgery and radiation/chemoradiation (S+RT/CRT) at 5, 10 and 15 years post-treatment.

RESULTS: A total of 319 patients were included. P16 positive patients and non-smokers had significantly higher long-term (5, 10 and 15-year) OS. Smokers and p16 negative patients treated with S+RT/CRT had improved long-term OS compared to patients who received CRT. Smokers and p16 negative patients had lower long-term AFS. Multivariate analysis showed improved OS was associated with p16 positivity (HR 0.42, 0.28-0.61) and surgery (HR 0.47, 0.32-0.69), whereas lower OS was associated with ECOG ≥ 2 (HR 2.46, 1.61-3.77), smoking (HR 2.37, 1.41-3.99) and higher stage (HR 1.68, 1.05-2.68).

CONCLUSIONS: In smokers and p16-negative OPSCC patients, primary surgery may be associated with improved long-term survival and dysphagia-related outcomes.