SABCS 2017: Extended Trastuzumab Treatment in Early-Stage HER2-Positive Breast Cancer
Data from the phase III SOLD trial, presented at the 2017 San Antonio Breast Cancer Symposium (SABCS; Abstract GS3-04), demonstrated continued support of the current practice of extended 12-month trastuzumab treatment in women with early-stage HER2-positive breast cancer, according to Heikki Joensuu, MD, at the time Professor in the Department of Oncology at the University of Helsinki, and colleagues. Disease-free survival after 9 weeks of adjuvant trastuzumab and standard chemotherapy was not comparable to disease-free survival after 12 months of adjuvant trastuzumab and standard chemotherapy
It should be noted that the researchers found no substantial difference in the secondary endpoints of distant disease–free survival and overall survival between the 12-month trastuzumab arm and the 9-week trastuzumab arm. Indeed, 5-year distant disease–free survival was 93.2% in the 9-week arm and 94.2% in the 12-month arm; 5-year overall survival was 94.7% in the 9-week arm and 95.9% in the 12-month arm.
Cardiac failure occurred in 3% and 2% of patients in the 12-month and 9-week arms, respectively. Patients in the 9-week arm had significantly higher cardiac left-ventricular ejection fractions than patients in the 12-month arm, but the absolute differences were small, and the ejection fractions mostly returned to the baseline level within 3 years after the date of randomization. “The shorter trastuzumab treatment was safer to the heart than the longer treatment,” noted Dr. Joensuu.