Upfront surgery versus definitive radiotherapy: competing risk analyses for cancer-specific and noncancer mortality in oropharyngeal cancer

Abstract

Purpose: The optimal treatment strategy for oropharyngeal cancer (OPC) is undetermined. We aim to compare the survival outcomes of OPC patients treated with upfront surgery versus definitive radiotherapy (RT).

Methods: A total of 8057 cases were retrieved from the Surveillance, Epidemiology, and End Results database. Primary endpoints were cancer-specific and noncancer mortalities, which were estimated using cumulative incidence function and compared by Gray's test. Univariate and multivariate Fine-Gray subdistribution hazard models were used to estimate the effects of treatment modality on mortality. Subgroup analyses were performed in propensity-score-matched cohorts. All the analyses were conducted separately in human papillomavirus (HPV)-negative and HPV-positive cohorts.

Results: In the HPV-negative cohort, definitive RT was independently associated with increased risk of cancer-specific mortality (adjusted subdistribution hazard ratio [SHR], 1.31; 95% confidence interval [CI], 1.05-1.64; P = 0.017) and noncancer mortality (adjusted SHR, 1.59; 95% CI 1.13-2.25; P = 0.008). In the HPV-positive cohort, definitive RT was independently associated with increased risk of cancer-specific mortality (adjusted SHR, 1.51; 95% CI 1.23-1.85; P < 0.001) and noncancer mortality (adjusted SHR, 1.53; 95% CI 1.11-2.12; P = 0.009).

Conclusion: Upfront surgery is a superior treatment modality compared with definitive RT in terms of lowering cancer-specific and noncancer mortality in OPC patients, regardless of HPV status. Further prospective clinical trials are needed to confirm our findings.

Keywords: Cancer-specific mortality; Competing risk; Non-cancer mortality; Oropharyngeal cancer; Radiotherapy; Surgery.