Survival Among Breast Cancer Patients: Comparison of the U.S. Military Health System with the Surveillance, Epidemiology and End Results Program

Introduction: Accessibility to health care is important to cancer survival. The U.S. military health system (MHS) provides universal health care access. However, whether the universal care has been translated into improved cancer survival is unknown. We compared survival of patients with breast cancer in the MHS with that in the U.S. general population and assessed the differences in cancer stage at diagnosis and treatment receipt between the two populations.

Methods: The MHS patients (n = 31,548) were identified from the Department of Defense's (DoD) Automated Central Tumor Registry (ACTUR). Patients in the U.S. general population (n = 63,096) were identified from the Surveillance, Epidemiology, and End Results (SEER) program. The two populations were matched on age, race, and diagnosis year. Multivariable Cox regression hazard modeling was used to estimate hazard ratios (HRs) comparing ACTUR with SEER. Multivariable logistic regression was used to estimate odds ratios (ORs) comparing stage and treatment receipt.

Results: ACTUR patients exhibited a 24% lower overall mortality than the SEER patients (HR = 0.76, 95% CI, 0.71-0.80). They were less likely to present with later stage compared to the SEER patients (OR = 0.61, 95% CI, 0.55-0.67 for stage IV tumors). The ACTUR patients with stages I-III tumors were more likely to receive surgery (OR = 1.35, 95% CI, 1.20-1.52) but less likely to receive radiation (OR = 0.91, 95% CI, 0.88-0.94). The survival advantage of ACTUR patients remained regardless of surgery or radiation receipt.

Conclusions: Breast cancer patients with universal health care access had improved survival compared to patients in the general population.