Age at Breast Cancer Diagnosis and Short-Term Postoperative Outcomes for Women Treated in a Universal Health System

Introduction: Surgery is an essential component of breast cancer treatment. Surgical complications may impact receipt of adjuvant therapy and long-term outcomes. Differences in insurance coverage and access to care by patient age in the general U.S. population may affect breast cancer diagnosis and surgery and thus age comparisons in research. We compared postoperative outcomes following breast cancer surgery between age groups in the U.S. Military Health System, which provides beneficiaries access to comprehensive care across the lifespan. Methods: We identified women aged ≥18 years with stage I–III breast cancer diagnosed from 2001 to 2014 undergoing surgery without reconstruction in the MilCanEpi database. Multivariable Poisson regression estimated the adjusted risk ratios (ARRs) with 95% confidence intervals (CIs) in association with age at diagnosis (18-39, 40-49, 50-64, and ≥65) for 30-day general and breast complications (surgical site infection, seroma, hematoma, or lymphedema), reoperation, and hospital readmission while controlling for potential confounders. Results: The study included 7835 women who were 18-39 (9.2%), 40-49 (23.6%), 50-64 (42.7%), and ≥65 (24.5%). The overall risk of general or breast complications did not differ significantly by age when controlled for demographic, tumor, and treatment variables. However, women aged 40-49 had a statistically increased adjusted risk of seroma (ARR = 1.50; 95% CI = 1.03-2.18) compared to women aged 50-64. No significant age-related differences were observed for reoperation or hospital readmission after adjustment. Conclusion: In the Military Health System, the overall risk of 30-day postoperative complications and hospital readmissions were not statistically different by age after adjustment for clinical and demographic factors. The findings support that surgical decision-making continue to prioritize tumor characteristics, comorbidity burden, and other clinical factors rather than age alone when assessing perioperative risk.