Summary

The 2005 results of large randomized trials, including the Trastuzumab in Treating Women with Primary Breast Cancer [HERA; NCT00045032] trial, demonstrated statistically significant disease-free survival benefit for 1 year of treatment with trastuzumab compared with observation in patients with human epidermal growth factor receptor 2-positive early breast cancer. After 2005, the HERA trial focused on the secondary objective of comparing 2 years of trastuzumab treatment with 1 year of treatment, and this article discusses the results of this analysis.