Abstract
BACKGROUND: Breast-conserving surgery combined with axillary lymph node dissection and radiotherapy or mastectomy are definitive treatments for women with early-stage breast cancer. Little is known about breast cancer treatment for women with disabilities. OBJECTIVE: To compare initial treatment for early-stage breast cancer between women with and without disabilities and to examine the association of treatment differences and survival. DESIGN: Retrospective cohort study. SETTING: 11 Surveillance, Epidemiology, and End Results (SEER) Program tumor registries. PARTICIPANTS: 100,311 women who received a diagnosis of stage I to IIIA breast cancer at 21 to 64 years of age from 1988 to 1999. Women who qualified for Social Security Disability Insurance (SSDI) and Medicare at breast cancer diagnosis were considered disabled. MEASUREMENTS: Receipt of breast-conserving surgery versus mastectomy. For women who had breast-conserving surgery (n = 49 166), the authors examined receipt of radiotherapy and axillary lymph node dissection. Survival was measured from diagnosis until death or until 31 December 2001. RESULTS: Women with SSDI and Medicare coverage had lower rates of breast-conserving surgery than other women (43.2% vs. 49.2%; adjusted relative risk, 0.80 [95% CI, 0.76 to 0.84]). Among women who had breast-conserving surgery, women with SSDI and Medicare coverage were less likely than other women to receive radiotherapy (adjusted relative risk, 0.83 [CI, 0.77 to 0.90]) and axillary lymph node dissection (adjusted relative risk, 0.81 [CI, 0.74 to 0.90]). Women with SSDI and Medicare coverage had lower survival rates than those of other women in all-cause mortality (adjusted hazard ratio, 2.02 [CI, 1.88 to 2.16]) and breast cancer-specific mortality (adjusted hazard ratio, 1.31 [CI, 1.18 to 1.45]). Results were similar after adjustment for treatment differences. LIMITATIONS: Findings are limited to women who qualified for SSDI and Medicare. No data on adjuvant chemotherapy and hormonal therapy were available, and details about the underlying disability were lacking. CONCLUSIONS: Women with disabilities had higher breast cancer mortality rates and were less likely to undergo standard therapy after breast-conserving surgery than other women. Differences in treatment did not explain the differences in breast cancer mortality rates.