Dr. Hershman on the Use of Endocrine Therapy in Premenopausal HR+/HER2- Breast Cancer

Dawn Hershman, MD, MS, professor of medicine and epidemiology, leader of the Breast Cancer Program of the Herbert Irving Comprehensive Cancer Center at Columbia University, discusses the use of endocrine therapy in premenopausal women with early-stage hormone receptor (HR)—positive, HER2-negative breast cancer.

The phase III SOFT and TEXT trials demonstrated the benefit of ovarian function suppression (OFS) plus an aromatase inhibitor (AI) versus tamoxifen alone in premenopausal women with early-stage HR-positive, HER2-negative disease. However, the combination is very toxic, says Hershman.

Research shows that only about half of patients are taking their therapy 80% of the time after 5 years. Reasons for discontinuation often include depression, hot flashes, difficulty sleeping, severe bone pain, and mood problems. Additionally, AIs can increase the risk for osteoporosis and sometimes cardiovascular disease, adds Hershman.

Investigators have designed risk prediction models to predict which patients need more intensive treatment and spare those who do not. At Dana-Farber Cancer Institute, researchers led by Meredith M. Regan, ScD, created a risk prediction model based on age, tumor characteristics, grade, and lymph node involvement to determine a patient’s risk profile. If the patient is young and falls into the high-risk category, OFS plus an AI should be given; the same is true if the patient has HER2-positive disease, says Hershman. However, if the patient has a smaller, low-grade cancer with no lymph node involvement, tamoxifen alone may suffice, concludes Hershman.