Factors Associated With Receipt of Radiation Therapy for Rectal Cancer

Appropriate treatment for cancer is vital to increasing the likelihood of survival; however, for rectal cancer, there are demonstrated disparities in receipt of treatment by race/ethnicity and socioeconomic status. We evaluated factors associated with receipt of appropriate radiation therapy for rectal cancer using data from the Florida Cancer Data System that had been previously enriched with detailed treatment information collected from a Centers for Disease Control and Prevention Comparative Effectiveness Research study. This treatment information is not routinely available in cancer registry data and represents a unique data resource.

Using multivariable regression, we evaluated factors associated with receiving radiation therapy among rectal cancer cases stage II/III. Our sample (n=403) included cases diagnosed in Florida in 2011 who were 18 years and older. Cases clinically staged as 0/I/IV were excluded.

Older age (odds ratio=0.96; 95% confidence interval, 0.94-0.97), the presence of one or more comorbidities (0.61; 0.39-0.96), and receipt of surgical intervention (0.44; 0.22-0.90) were associated with lack of radiation.

In this cohort of patients, sociodemographic factors such as race/ethnicity, insurance status, and socioeconomic status, did not influence the receipt of radiation. Further research is needed, however, to understand why aging, greater comorbidity, and having surgery present a barrier to radiation therapy, particularly given that it is a well-tolerated treatment in most patients.