Long-term community-based results of breast-conserving therapy in early-stage breast cancer

Background Multicenter clinical trials conducted primarily at academic centers have shown that breast-conserving therapy (BCT) and mastectomy lead to equivalent overall survival (OS) for women with early-stage breast cancer. Objective To determine rates of BCT and OS after conservation therapy in a large urban community practice, compare them with national rates, and identify risk factors for survival. Methods We identified 1,172 T1-2, N0 breast cancer patients diagnosed during 1997-2007 in our hospital tumor registry and compared the rates of BCT and adjuvant radiotherapy with a similar population in the SEER [Surveillance, Epidemiology, and End Results] database (N = 232,898) for the same treatment period. Cox proportional hazards models were used to assess the influence of age at diagnosis, tumor grade, biomarker status, margin status, and receipt of hormones, radiation, or chemotherapy on OS after BCT. Results The rate of breast-conserving surgery (BCS) was higher in our practice compared with the national average (90.9% and 66.4%, respectively). The rate of adjuvant radiation after BCS in our practice was 93.7%; survival estimates were higher for patients treated with adjuvant radiation across all age groups, compared with the national estimates (92.5% and 72.9%). Younger age and receipt of radiation were associated with improved survival. Limitations Retrospective study design; confounding factors such as comorbidities were not considered. Conclusions We had high rates of BCT and adjuvant radiation in early-stage breast cancer patients in our community practice, which resulted in excellent survival rates that compared favorably with those in large academic centers and emphasizes the role of appropriate use of adjuvant radiation.