ASCO 2017: Duration of Adjuvant Trastuzumab for HER2-Positive Breast Cancer
Results from the phase III Italian Short-HER study indicate that a shorter course of trastuzumab may reduce the rate of severe cardiac toxicity—as well as the cost of therapy—without compromising overall survival in patients with HER2-positive breast cancer. These findings were presented by Pier F. Conte, MD, of the Istituto Oncologico Veneto IRCCS in Italy, at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 501).
One year of trastuzumab with chemotherapy is considered the standard adjuvant treatment for HER2-positive breast cancer. The efficacy of less extended trastuzumab therapy has been the topic of investigation.
A total of 1254 patients from 82 centers received either 1 year of trastuzumab plus chemotherapy (long treatment) or 9 weeks of trastuzumab plus chemotherapy (short treatment). The 5-year overall survival was nearly identical between the two treatment arms (95.1% in the long treatment groups vs 95.0% in the short treatment group).
In terms of cardiac toxicity, there was an ongoing decline in left ventricular ejection fraction in the long treatment group, but there was a much slower decline in the short treatment group over 18 months. In addition, there were fewer cardiac events with the short therapy compared with the long therapy (32 vs 90, P<.0001).