Temporal trends in oropharyngeal cancer treatment and survival: 1998-2009

Objectives/hypothesis: To describe temporal trends of surgical and nonsurgical treatment for advanced oropharyngeal cancer, and to report contemporary survival estimates and factors associated with survival.

Study design: Patients diagnosed between 1998 and 2009 with a first primary, invasive, advanced-stage squamous cell carcinoma of the oropharynx were selected from the National Cancer Database (N = 67,239). The outcomes of this study were first primary treatment and survival. Treatment was defined as chemotherapy with concurrent radiation (ChemoRT), radiation alone (RT), and surgery.

Methods: Two-tailed t tests were used to evaluate the statistical significance of treatment type by sociodemographic variables. Multivariate log binomial regression models were used to estimate risk ratio and 95% confidence interval of select treatments (ChemoRT vs. RT and ChemoRT vs. surgery). For survival analysis, all variables were entered into a single model to test for violations in the proportional hazards (PH) assumption. All PH analyses were stratified by stage and age at diagnosis, and insurance status.

Results: The total analytic cohort included 43,983 patients. Sociodemographic variables predicted type of treatment and survival. In addition, chemoradiation was increasingly used during this time period and was associated with improved survival. There was no decrease in mean or median age of patients during this time period to explain the improved survival.

Conclusions: These results confirmed previously reported trends of increasing use of nonsurgical therapy in the treatment of advanced oropharyngeal cancers. In addition, this analysis describes numerous factors that were predictive of overall survival including race, insurance, increasing use of chemoradiation, and socioeconomic status.