Abstract
535
Background: Colon cancer is the third most frequent cancer diagnosis, and primary payer status has been shown to be associated with treatment modalities and survival in cancer patients. The goal of our study was to determine between-insurance differences in survival in patients with pathologic stage III colon cancer using data from the National Cancer Data Base (NCDB). Methods: We identified 130,998 patients with pathologic stage III colon cancer in the NCDB diagnosed between 2004 and 2012. Kaplan-Meier curves and multivariable Cox regression models were estimated to determine the association between insurance status and survival. Results: Private insurance patients were 41% less likely than Medicaid patients to die, 28% less likely to die than uninsured patients, and 14% less likely to die than those with Medicare (p<0.01). Medicare patients were 18% were less likely to die compared to uninsured patients (p<0.01) and 19% less likely to die compared to Medicaid patients (p<0.01). Medicaid and noninsured patients had comparable likelihoods of dying (p=0.76). Those with no comorbidities were 36% less likely to die than those with 2+ comorbidities (p<0.01). Each additional year in age added a 3% likelihood of dying (p<0.01). Patients with chemotherapy were 57% less likely to die compared to patients not receiving chemotherapy (p<0.01). Private insurance had the greatest percentage of patients receiving chemotherapy at 82%. Conclusions: Of all variables examined, chemotherapy provided the greatest increased chance of survival. Comorbidities were also a significant contributor to survival. Private and Medicare patients were likely to survive longer than uninsured and Medicaid patients. Furthermore, having Medicaid did not provide an advantage in survival over having no insurance. [Table: see text]