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.
- 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]