Cardiac Dysfunction in the Trastuzumab Clinical Trials Experience

Patients treated with trastuzumab were found to be at an increased risk for CD. The incidence was greatest in patients receiving concomitant trastuzumab and anthracycline plus cyclophosphamide (27%). The risk was substantially lower in patients receiving paclitaxel and trastuzumab (13%) or trastuzumab alone (3% to 7%); however, most of these patients had received prior anthracycline therapy. CD was noted in 8% of patients receiving anthracycline plus cyclophosphamide and 1% receiving paclitaxel alone. Most trastuzumab-treated patients developing CD were symptomatic (75%), and most improved with standard treatment for congestive heart failure (79%).

Trastuzumab is associated with an increased risk of CD, which is greatest in patients receiving concurrent anthracyclines. In most patients with metastatic breast cancer, the risk of CD can be justified given the improvement in overall survival previously reported with trastuzumab.