Abstract
357
Background: Optimal imaging utilization for staging of oropharynx cancer is not well defined.
Methods: The linked Surveillance, Epidemiology, and End Results-Medicare database was used to identify and compare patient and disease profiles, treatment, mortality, and overall cost for patients with oropharynx cancer who underwent initial imaging between 2006 and 2011. The primary outcome was 3-year cancer specific survival (CSS).
Results: One thousand seven hundred and sixty-five patients underwent diagnostic imaging (n = 1,765). Of those a select population received CT alone as their imaging modality (n=202), a smaller population underwent MRIs with or without CT, but without PET imaging (n=91), while many patients’ initial imaging included a PET exam (n=1,472). The difference in three-year CSS was nearly significant for patients who underwent a CT alone as compared to PET (hazard ratio [HR] 1.319; 95% CI 0.987-1.764; P=0.0617) and significant for MRI as compared PET (HR 1.810; 95% CI 1.234-2.665; P = 0.0024) in a Cox proportional hazards model. Three-year overall survival (OS) was not significant with the CT alone patients having a HR of 1.209 (95% CI 0.951-1.538; P = 0.1210) or the MRI imaged patients HR 1.334 (95% CI 0.951-1.872; P= 0.0947). Females were significantly more likely to get a MRI (OR 2.534; 95% CI 1.600-4.013; P = <0.001) or CT alone (OR 1.554; 95% CI 1.115-2.165; P = 0.0093), than PET based staging at diagnosis, and also had poorer CSS (HR, 1.572; 95% CI 1.261-1.958; P = <0.0001).
Conclusions: Patients who were initially staged with PET vs MRI had improved CSS. PET vs CT alone CSS was nearly significant. In addition, female patients were less likely to have PET imaging and also had a significantly lower survival.