Abstract
BACKGROUND: The proxy marker for human papillomavirus (HPV), p16, is included in the new AJCC 8th/UICC 8th staging system, but due to incongruence between p16 status and HPV infection, single biomarker evaluation could lead to misallocation of patients. We established nomograms for overall survival (OS) and progression-free survival (PFS) in patients with oropharyngeal squamous cell carcinoma (OPSCC) and known HPV-DNA and p16 status, and validated the models in cohorts from high- and low-prevalent HPV countries. METHODS: Consecutive OPSCC patients treated in Denmark, 2000-2014 formed the development cohort. The validation cohorts were from Sweden, Germany, and the United Kingdom. We developed nomograms by applying a backward-selection procedure for selection of variables, and assessed model performance. RESULTS: In the development cohort, 1313 patients, and in the validation cohorts, 344 German, 503 Swedish and 463 British patients were included. For the OS nomogram, age, gender, combined HPV-DNA and p16 status, smoking, T-, N-, and M-status and UICC-8 staging were selected, and for the PFS nomogram the same variables except UICC-8 staging. The nomograms performed well in discrimination and calibration. CONCLUSIONS: Our nomograms are reliable prognostic methods in patients with OPSCC. Combining HPV DNA and p16 is essential for correct prognostication. The nomograms are available at www.orograms.org .