Impact of Pathologic Complete Response on Breast Cancer Recurrence and Mortality
Posted: Thursday, January 31, 2019
Data presented at the 2018 San Antonio Breast Cancer Symposium (SABCS; Abstract GS2-03) indicate that pathologic complete response to neoadjuvant chemotherapy is associated with improved disease recurrence and survival in breast cancer, with or without additional adjuvant therapy. Laura Spring, MD, of Massachusetts General Hospital Cancer Center, and colleagues concluded that adjuvant chemotherapy may be halted in some cases where pathologic complete response has been achieved.
“The finding possibly reflects tumor biology, wherein tumors sensitive to neoadjuvant therapy in breast and lymph nodes are also typically sensitive to the therapy in micrometastatic sites,” Dr. Spring said in an SABCS press release. “Presence of complete response in breast and axilla is likely associated with complete response in micrometastatic sites, minimizing the added benefit from additional adjuvant therapy.”
The investigators collected data from 52 studies, totaling 27,895 patients. The achievement of pathologic complete response overall was associated with a reduction in disease recurrence when compared with the absence of pathologic complete response, with a hazard ratio of 0.31. In both patients with triple-negative breast cancer and HER2-positive breast cancer, disease recurrence dropped significantly when pathologic complete response was attained (hazard ratio = 0.18 and 0.32, respectively). A reduction in mortality was seen when pathologic complete response was achieved after neoadjuvant chemotherapy in all cancer subtypes. In addition, reduced recurrence of disease was seen in studies where patients achieved pathologic complete response with or without adjuvant chemotherapy.
“Overall, the study findings from our team support the concept of therapeutic escalation/de-escalation strategies in the adjuvant setting based on initial neoadjuvant response and highlight the need for additional research to personalize the ‘right’ amount of therapy for patients with breast cancer,” stated senior author Aditya Bardia, MD, MPH, also of Massachusetts General Hospital.
Disclosure: Study authors’ disclosures can be found at SABCS.org.