Autoimmunity and Benefit from Trastuzumab Treatment in Breast Cancer: Results from the HERA Trial.

Abstract

BACKGROUND/AIM:This study sought to determine whether an autoimmune background could identify patients with HER2-positive early breast cancer (EBC) who derive differential benefit from primary adjuvant trastuzumab-based therapy. PATIENTS AND METHODS:HERA is an international randomized trial of 5,102 women with HER2-positive EBC, who were enrolled to either receive adjuvant trastuzumab or not. In this exploratory analysis, the interaction between autoimmune history and the magnitude of trastuzumab benefit was evaluated. RESULTS:A total of 5,099 patients were included in the current analysis. Among them, 325 patients (6.4%) had autoimmune disease history, 295 of whom had active disease. Patients were randomly assigned to trastuzumab or no-trastuzumab groups. Similar reductions in the risk of events in patients with and without autoimmune history were observed (interaction p=0.95 for disease-free survival, and p=0.62 for overall survival). CONCLUSION:No evidence of a differential benefit from trastuzumab in patients with a medical history of autoimmune disease was found.