Residual cancer burden (RCB) was prognostic for survival among women with breast cancer who received neoadjuvant chemotherapy, according to a study published in the Journal of Clinical Oncology.1

Neoadjuvant chemotherapy is approved for the treatment of high-risk, early breast cancer based on pathologic complete response (pCR) rate. This study attempted to determine if RCB is a prognostic factor in this patient setting.

Data from 1981 patients in 5 cohorts underwent a pathologic review to determine the continuous RCB index. RCB was 0 for pCR, and categorized as RCB-I, RCB-II, and RCB-III for presence of residual disease.

One cohort received fluorouracil, doxorubicin, and cyclophosphamide (FAC), and 3 cohorts received paclitaxel followed by FAC (T/FAC). The fifth cohort received trastuzumab plus sequential paclitaxel and fluorouracil, epirubicin, and cyclophosphamide (H+T/FEC).

The breast cancer phenotypes included HR-positive/HER2-negative, HER2-positive, or triple receptor-negative.

The 10-year relapse-free survival (RFS) rates were associated with RCB category with median follow-up time ranging from 6.4 to 16.4 years.

RCB-0, RCB-I, RCB-II, and RCB-III resulted in RFS rates of 95%, 85%, 62%, and 42%, respectively, in the FAC cohort; 86%, 85%, 68%, and 46%, respectively, in the combined T/FAC cohorts; and 95%, 77%, 47%, and 21%, respectively, in the H+T/FEC cohort.

RELATED: Breast Cancer: Zoledronic Acid Every 12 Weeks Non-inferior to Every 4 Weeks

In the T/FAC cohorts, the RFS rates were 86%, 81%, 55%, and 23%, respectively, for triple receptor–negative disease and 83%, 97%, 74%, and 52%, respectively, for HR-positive/HER2-negative disease.

The authors suggest that pathologic response is prognostic among the different breast cancer phenotypes. They noted, however, that independent validation is needed.

Reference

  1. Symmans WF, Wei C, Gould R, et al. Long-term prognostic risk after neoadjuvant chemotherapy associated with residual cancer burden and breast cancer subtype. J Clin Oncol. 2017 Jan 30. doi: 10.1200/JCO.2015.63.1010 [Epub ahead of print]