For women with HER2-positive early breast cancer treated with an anthracycline-based regimen followed by trastuzumab (Herceptin), concurrent therapy with the angiotensin-converting enzyme (ACE) inhibitor lisinopril can help to prevent a decline in left-ventricular ejection fraction (LVEF) below 50%, investigators in a community-based study found.
Among 424 women with HER2-positive early-stage breast cancer, the rate of LVEF decline to below 50% was 21.4% among patients randomized to receive an anthracycline-based regimen, compared with 4.1% for patients who were treated with a non–anthracycline-based regimen.
Among patients in the anthracycline arm, treatment with lisinopril, but not carvedilol or placebo, was associated with significant protection against LVEF decline, reported Pamela N. Munster, MD, of the Helen Diller Family Comprehensive Cancer Center at the University of California, San Francisco.
“The findings of this study suggested that the drop in left ventricular ejection fraction to below 50% or to below normal was much larger than previously reported in the anthracycline group,” she said in a video presentation during a poster discussion session at the American Society of Clinical Oncology annual meeting. (Abstract 509).
Although HER2 inhibition is a highly effective treatment strategy for patients with HER2-positive tumors, trastuzumab-associated decline in LVEF and clinical heart failure can result in treatment interruption or discontinuation of therapy, the authors noted.
They conducted the prospective randomized trial to see whether trastuzumab-associated cardiotoxicity could be mitigated by concurrent use of either an ACE inhibitor or beta-blocker.
They enrolled women with early HER2-positive breast cancer from 127 community-based oncology centers.
The patients were randomly assigned to receive either an anthracycline- or non–anthracycline-containing regimen, followed by a year of trastuzumab, and were then randomized again to receive either lisinopril, carvedilol, or placebo concurrently with trastuzumab.
The patients were assessed for cardiotoxicity every 12 weeks with a multiple-gated acquisition (MUGA) scan and echocardiogram. Cardiotoxicity was defined as an absolute decrease in LVEF of 10% or more, or at least 5% decrease in LVEF below 50% at baseline.
Small LVEF declines in all
The investigators observed that all patients in the study experienced a small but not clinically relevant decrease in LVEF during trastuzumab therapy, and that this decline was not significantly ameliorated by any of the interventions.
However, as noted before, among patients assigned to anthracycline-based regimens the rate of decline to LVEF below 50% was 21.4%, compared with 4.1 for patients assigned to non–anthracycline regimens.
LVEF declines of at least 10% occurred in 5.5% of patients who received anthracyclines, and in 14.4% of those who received a non-anthracycline regimen.
Among patients who received anthracycline, only 10.8% randomized to receive lisinopril prophylaxis experienced a decline in LVEF, compared with 30.5% assigned to placebo (P = .045).
“In contrast, while carvedilol showed a numerical prevention of LVEF below 50% to 22.8%, this was not statistically significant,” Dr. Munster said.
Decreases in LVEF of 10% or greater within the normal LVEF range were similar in both chemotherapy arms and were not affected by either lisinopril or carvedilol.
“Lisinopril was well tolerated in this group, even in patients without hypertension,” she said.
“In women treated in a community-based environment who could benefit from anthracyclines or where anthracyclines are indicated, one should anticipate the decrease in left ventricular ejection fraction to below normal to be larger than is reported by other groups. However, this could be prevented by lisinopril,” she concluded.