Objective: To determine the impact of tumor biology on rates of breastconserving surgery and pathologic complete response (pCR) after neoadjuvant chemotherapy.
Background: The impact of tumor biology on the rate of breastconserving surgery after neoadjuvant chemotherapy has not been well studied.
Methods: We used data from ACOSOG Z1071, a prospective, multicenter study assessing sentinel lymph node surgery after neoadjuvant chemotherapy in patients presenting with nodepositive breast cancer from 2009 through 2011, to determine rates of breastconserving surgery and pCR after chemotherapy by approximated biologic subtype.
Results: Of the 756 patients enrolled on Z1071, 694 had findings available from pathologic review of breast and axillary specimens from surgery after chemotherapy. Approximated subtype was triplenegative in 170 (24.5%), human epidermal growth factor receptor 2 (HER2)positive in 207 (29.8%), and hormonereceptorpositive, HER2negative in 317 (45.7%) patients. Patient age, clinical tumor and nodal stage at presentation did not differ across subtypes. Rates of breastconserving surgery were significantly higher in patients with triplenegative (46.8%) and HER2positive tumors (43.0%) than in those with hormonereceptorpositive, HER2negative tumors (34.5%) (P = 0.019). Rates of pCR in both the breast and axilla were 38.2% in triplenegative, 45.4% in HER2positive, and 11.4% in hormonereceptorpositive, HER2negative disease (P 0.0001). Rates of pCR in the breast only and the axilla only exhibited similar differences across tumor subtypes.
Conclusions: Patients with triplenegative and HER2positive breast cancers have the highest rates of breastconserving surgery and pCR after neoadjuvant chemotherapy. Patients with these subtypes are most likely to be candidates for less invasive surgical approaches after chemotherapy.
- Breast cancer
- Breast conservation
- Neoadjuvant chemotherapy
- Tumor subtype
ASJC Scopus subject areas