Abstract
BACKGROUND: Due to their differing carcinogenesis, prognosis and clinical manifestation, human papillomavirus (HPV)-associated and HPV-negative oropharyngeal squamous cell carcinoma (OSCC) have been classified separately as two entities since the 8th edition of the AJCC/UICC TNM staging system (UICC 8). MATERIALS AND METHODS: A total of 524 patients with OSCC treated between 2000 and 2016 at the Department of Otorhinolaryngology, Head and Neck Surgery of the University Hospital Muenster, Germany, were examined for the detection of HPV type 16-specific DNA (HPV16-DNA), nicotine and alcohol consumption and the influence of therapy on overall survival (OS). RESULTS: There was a significant increase in the annual prevalence of HPV16-DNA-positive OSCC from 40% (n = 12/30) in 2000 to 46% (n = 18/39) in 2016 (p = 0.025, β = 0.539). Of the HPV16-DNA-positive OSCC, 89% (n = 212) were downgraded on the basis of UICC 8 compared to UICC 7. In the overall collective, frequent alcohol and nicotine (≥ 10 pack years) consumption showed a significant negative influence on OS (p = 0.004 and p = 0.009, respectively). Frequent alcohol consumption was also prognostically relevant in the HPV16-DNA-negative group (p = 0.049). In the HPV16-DNA-positive group, the prognosis for OS according to UICC 8 showed no statistically significant difference between stages I and II (p = 0,481), or between III and IV (p = 0.439). CONCLUSIONS: The current UICC 8 improves the prognostic stratification of OSCC due to the separation of HPV-positive and HPV-negative tumors in comparison to UICC 7. However, the prognostic significance of UICC 8 for HPV-associated OSCC is still insufficient. In the future, alcohol and nicotine consumption could influence the UICC classification in order to further improve prognostic significance.