Comparison of survival among colon cancer patients in the u.s. military health system and patients in the surveillance, epidemiology, and end results (seer) program

Background: Access to health care is associated with cancer survival. The U.S. military health system (MHS) provides universal health care to beneficiaries, reducing barriers to medical care access. However, it is unknown whether the universal care has translated into improved survival among patients with colon cancer. We compared survival of patients with colon cancer in the MHS to that in the U.S. general population and assessed whether stage at diagnosis differed between the two populations and thus could contribute to survival difference. Methods: The data were from Department of Defense's (DoD) Automated Central Tumor Registry (ACTUR) and the NCI's Surveillance, Epidemiology, and End Results (SEER) program, respectively. The ACTUR (N 11,907) and SEER patients (N 23,814) were matched to demographics and diagnosis year with a matching ratio of 1:2. Multivariable Cox regression model was used to estimate all-cause mortality for ACTUR compared with SEER. Results: ACTUR patients exhibited better survival than their SEER counterparts (HR, 0.82; 95% confidence interval, 0.79-0.87) overall and in most subgroups by age, in both men and women, and in whites and blacks. The better survival remained when the comparison was stratified by tumor stage. Conclusions: Patients with colon cancer in a universal health care system had better survival than patients in the general population.