Independent Adjudication of Symptomatic Heart Failure With the Use of Doxorubicin and Cyclophosphamide Followed by Trastuzumab Adjuvant Therapy: A Combined Review of Cardiac Data From the National Surgical Adjuvant Breast and Bowel Project B-31 and the North Central Cancer Treatment Group N9831 Clinical Trials

Abstract

An independent Adjuvant Cardiac Review and Evaluation Committee (ACREC) systematically reviewed cases of symptomatic heart failure events to uniformly define the cardiac event rate across two large trials (National Surgical Adjuvant Breast and Bowel Project [NSABP] B-31 and North Central Cancer Treatment Group [NCCTG] N9831) that assessed the addition of trastuzumab to standard adjuvant chemotherapy. The committee was composed of six independent oncologists and cardiologists. A retrospective review of patients with a cardiac event was performed by the primary investigators of the trials. The ACREC prospectively established criteria for determining a symptomatic heart failure event. Recovery status was determined from documented resolution of signs and symptoms. Potential risk factors were also assessed. Medical records for a total of 173 patients were reviewed: 40 in the chemotherapy-alone arm and 133 in the trastuzumab arm. Trastuzumab-treated patients had a 2.0% incidence of symptomatic heart failure events compared with 0.45% in the chemotherapy-alone arm. Complete or partial recovery was observed in 86.1% of trastuzumab-treated patients with symptomatic heart failure events. Of five patients who died, only one patient had received trastuzumab. Independent predictors for cardiac events were age older than 50 years, a low ejection fraction at the start of paclitaxel treatment, and trastuzumab treatment. The incidence of symptomatic heart failure events is 2.0% in patients treated with adjuvant trastuzumab, and the majority of these patients recover with appropriate treatment.