Treatment-related outcome of oropharyngeal cancer patients differentiated by HPV dictated risk profile: A Tertiary Cancer Centre series analysis

Background: To date, no treatment modality has been identified as more effective for oropharyngeal cancer (OPC), and no predictive factors are known to guide treatment decision for this disease. This retrospective study evaluates the differential effects of diverse treatment options for OPC according to patient risk profiles. Patients and methods: We considered two series of locally advanced squamous cell OPC patients treated with either surgery followed by radiotherapy (surgical series) or chemoradiation (CRT) with/without induction docetaxel, cisplatin and 5-fluorouracil (TPF) chemotherapy (CRT series). Smoking habits, tumor p16 expression/human papillomavirus (HPV) status and T and N stage were analyzed to stratify the patients according to Ang's risk profile (low, intermediate and high risk). Overall survival (OS) and disease-free survival were calculated with the Kaplan-Meier method. Results: Globally, 171 patients were considered, 56 in surgical and 115 in CRT series. Patients were stratified in low- (20% of surgical and CRT groups), intermediate- (23% and 41%) and high-risk (57% and 39%) groups. In the surgical series, 5-year OS was 54.5%, 46.9% and 40.0% in low, intermediate and high Ang's risk profiles, respectively, whereas in the CRT series those were 100%, 78.9% and 46.7%, respectively. In the multivariable analyses, adjusting for inhomogeneity between the treatment group, the CRT effect was significantly higher in the low- and intermediate-risk groups (P-value for the interaction treatment risk group = 0.034 in the OS analysis). Conclusions: In this retrospective analysis, low- and intermediate-risk OPC patients had a better survival when treated with CRT compared with open surgery followed by radiation therapy. These data suggest that different treatment approaches might be essential in determining outcome results.