Improvement of patient stratification in human papilloma virus-associated oropharyngeal squamous cell carcinoma by defining a multivariable risk score.

BACKGROUND Precise risk stratification models are necessary to determine patient selection for deintensifying treatment trials in human papilloma virus (HPV)-associated oropharyngeal squamous cell cancer (HPV+ OPSCC). METHODS We examined 526 cases with OPSCC treated at our department between 2002 and 2017. Every patient was classified after the 7th and 8th edition UICC staging manual. For HPV+ OPSCC, we calculated a simple risk score with four risk groups based on multivariable Cox regression analysis of clinical and lifestyle parameters (UICC 8th edition stage, tobacco/alcohol abuse, age, gender). RESULTS Two hundred and thirty-nine patients with OPSCC (45.4%) showed a positive histological HPV status. In comparison to UICC 8th edition stages, our proposed risk model showed a tendency for better stratification between risk strata I/III, I/IV, and II/IV (each p < 0.002) and I/II, II/III, and III/IV (each p < 0.09). CONCLUSION Age, gender, tobacco, and alcohol abuse should be added to the current UICC staging system in order to improve risk stratification in HPV+ OPSCC.