Factors associated with receipt of radiation therapy for rectal cancer.

Abstract

747 Background: Appropriate treatment for rectal cancer is vital to increasing the likelihood of survival. Disparities in receipt of appropriate radiation treatment have been observed with respect to race/ethnicity and socioeconomic status. We used enriched cancer registry data to identify alternative factors associated with receipt of appropriate radiation therapy for rectal cancer. Methods: Data were obtained from the Florida Cancer Data System and were enriched with detailed treatment information collected from a Centers for Disease Control and Prevention Comparative Effectiveness Research study. Using multivariable regression, we evaluated factors associated with receipt of radiation therapy among rectal cancer cases summary stage II/III. Our sample (n=403) included cases diagnosed in Florida in 2011 who were 18 years and older. Cases clinically staged as 0/1/4 were excluded. Though patients over age 80 years (n=67) and those with stage IIA disease (n=185) may not routinely be prescribed radiation, these cases were included in order to maximize the sample size. Results: Our sample was an average of 64 years-old, more often male (59%), NH White (56%), diagnosed with stage III disease (54%), insured (92%), had received surgical intervention (87%), chemotherapy (68%), or radiation (57%), were in the highest SES quartile (56%), and had one or more comorbid condition (57%). Older age (OR=0.96; 95%CI=0.94-0.97), the presence of more than one comorbidity (0.61; 0.39-0.96), and receipt of surgical intervention (0.44; 0.22-0.90) were predictors of not receiving radiation. Conclusions: Contrary to our hypothesis, socio-demographic 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 age, comorbidity, and surgery present a barrier to radiation, particularly given that radiotherapy is a well-tolerated modality.