Definitive radiochemotherapy or initial surgery for oropharyngeal cancer To what extent can p16 expression be used in the decision process?

Background The decision between definitive radio(chemo)therapy (RCT) or a surgical strategy, i.e. surgery +/- adjuvant radio(chemo)therapy for optimal treatment of oropharyngeal cancer is highly debated. Human papillomavirus(HPV)-related tumours are a distinct entity associated with p16 overexpression. While this represents a major prognostic factor, its predictive significance remains unknown. Results Among 183 consecutive unselected patients treated between 2009 and 2013 with a state-of-the-art surgical procedure +/- adjuvant radio(chemo)therapy or definitive RCT including intensity-modulated radiotherapy, 3-year disease-free survival (DFS) was 74 vs. 57%, respectively (p = 0.007). When focusing on p16+ patients (49%), there was no significant difference in tumour control rate between surgeryradio(chemo)therapy and the definitive RCT group (3-year DFS 83 vs. 82%, respectively; p = 0.48). However, delayed severe dysphagia was significantly lower in favour of definitive RCT: 35 vs. 4%, respectively; p = 0.0002. Conclusion Our results highlight distinct outcomes after definitive RCT or initial surgical treatment according to p16 status, which should thus be considered during the decision process.