CHICAGO—Aromatase inhibitors (AIs) have an unquestioned role to play in the treatment of postmenopausal women with breast cancer, but there is no single best approach for their use in all patients, Eric Winer, MD, said at the 8th Annual Lynn Sage Breast Cancer symposium. In a separate meeting presentation, Nancy Davidson, MD, cautioned physicians about the use of AIs in premenopausal women with hormone-receptor- positive breast cancer and chemotherapy-induced amenorrhea.
It’s not possible to provide a “simple answer” to the question of the best approach for use of AIs in women with heterogeneous breast tumors, said Dr. Winer, director of the Breast Oncology Center and associate professor of medicine, Harvard Medical School.
The optimal strategy for incorporating AIs into the adjuvant treatment of postmenopausal women with breast cancer has not been defined, Dr. Winer said. When given as initial therapy, AIs have improved disease-free survival but not overall survival. When given as part of a crossover clinical trial design, the drugs have increased both disease-free and overall survival. However, follow-up of patients treated with AIs has been limited. Although therapy in excess of 10 years may provide the most benefit, long-term safety and efficacy data are lacking, he commented.
Based on available data, Dr. Winer said he believes that AIs should be used in the treatment of postmenopausal women with breast cancer, but given the heterogeneous nature of breast tumors and the types of patients in this population, he suspects that there will not be a single overall governing strategy for administering the drugs.
Safety in Premenopausal Women
In her presentation on ovarian suppression/ ablation in premenopausal breast cancer patients, Dr. Davidson stressed that tamoxifen(Drug information on tamoxifen) is the standard of care for these women, that ovarian suppression/ ablation by surgery or LHRH agonists might be used in addition and is being studied, and that AIs are investigational in these women.
Dr. Davidson, professor of oncology and director of the Breast Cancer Research Program, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, pointed out that the amenorrhea caused by cytotoxic therapy is “not the same as menopause, and clinicians should think hard about the safety of AIs for such patients.”
She presented findings from a “sobering” case report involving the use of AIs in 45 women with chemotherapy-induced amenorrhea (J Clin Oncol 24:2444- 2447, 2006). The patients had a median age of 47 years and varied experience with AIs: 16 women received an AI as initial therapy, 20 were later switched to an AI, and 9 had extended AI therapy.