ASCO 2018: Weighing Benefits/Risks of Exemestane Therapy in Premenopausal Women With Breast Cancer
Posted: Wednesday, June 20, 2018
An analysis of distant recurrence rates in almost 6,000 premenopausal women with early hormone receptor–positive breast cancer indicates that those at highest risk of recurrence may benefit most from 5 years of treatment with the aromatase inhibitor exemestane plus ovarian function suppression (OFS), versus tamoxifen plus OFS or tamoxifen alone. For those at lower risk of distant recurrence, the challenging decision for both patients and physicians may depend on patient preference and tolerance, the investigators noted.
This analysis of the results of the randomized TEXT and SOFT trials was presented at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago (Abstract 503) and also published in The New England Journal of Medicine.
The exemestane-treated women with hormone receptor–positive, HER2-negative breast cancer and a high recurrence risk, as defined by clinicopathologic characteristics had a “10% to 15% absolute improvement in 8-year distant recurrence-free interval,” noted Meredith Regan, ScD, of Boston’s Dana-Farber Cancer Center, and colleagues. “That’s a big increase, and women in that situation might decide it’s worth it,” Dr. Regan noted in a Dana-Farber press release.
Conversely, for low-risk women, the benefit of escalating endocrine therapy versus tamoxifen alone was minimal. Between 96% and 97% experienced no distant recurrence regardless of the endocrine therapy used. For intermediate-risk patients, the exemestane regimen conferred a 4% to 5% benefit. As for toxicity, grade 3 or higher adverse events were observed in 32.3% of those in the exemestane–ovarian suppression group, 31.0% of the tamoxifen–ovarian suppression group, and 24.6% of the tamoxifen-alone group.
