Breast conservation after neoadjuvant chemotherapy: the MD Anderson cancer center experience.

PURPOSE: To determine patterns of local-regional recurrence (LRR) and ipsilateral breast tumor recurrence (IBTR) among patients treated with breast conservation therapy after neoadjuvant chemotherapy.

PATIENTS AND METHODS: Between 1987 and 2000, 340 cases of breast cancer were treated with neoadjuvant chemotherapy followed by conservative surgery and radiation therapy. Clinical stage at diagnosis (according to the 2003 American Joint Committee on Cancer system) was I in 4%, II in 58%, and III in 38% of patients. Only 4% had positive surgical margins.

RESULTS: At a median follow-up period of 60 months (range, 10 to 180 months), 29 patients had developed LRR, 16 of which were IBTRs. Five-year actuarial rates of IBTR-free and LRR-free survival were 95% and 91%, respectively. Variables that positively correlated with IBTR and LRR were clinical N2 or N3 disease, pathologic residual tumor larger than 2 cm, a multifocal pattern of residual disease, and lymphovascular space invasion in the specimen. The presence of any one of these factors was associated with 5-year actuarial IBTR-free and LRR-free survival rates of 87% to 91% and 77% to 84%, respectively. Initial T category (T1-2 v T3-4) correlated with LRR but did not correlate with IBTR (5-year IBTR-free rates of 96% v 92%, respectively, P =.19).

CONCLUSION: Breast conservation therapy after neoadjuvant chemotherapy results in acceptably low rates of LRR and IBTR in appropriately selected patients, even those with T3 or T4 disease. Advanced nodal involvement at diagnosis, residual tumor larger than 2 cm, multifocal residual disease, and lymphovascular space invasion predict higher rates of LRR and IBTR.