Hormone-blocking drug prevents ovarian failure, improves fertility in breast cancer patients

Women who received goserelin -- a synthetic version of a naturally occurring gonadotropin-releasing hormone (GnRH) -- during chemotherapy for breast cancer experienced an 8 percent ovarian failure rate compared to 22 percent for the control group two years after treatment. In addition, 21 percent of women who received goserelin became pregnant within the first 5 years post-treatment compared to only 11 percent of women who became pregnant in the control group during the same timeframe.

"POEMS is the first study to provide strong evidence that fertility prospects are improved following ovarian suppression during chemotherapy," said Halle C.F. Moore, M.D., a breast cancer oncologist at Cleveland Clinic and the study's lead investigator. "Preserving ovarian function is a vital survivorship issue for young breast cancer patients. In addition to improving prospects for fertility, this intervention should help avoid a variety of unwanted effects of early menopause."

Ovarian failure, or the development of early menopause, is a common long-term side effect of chemotherapy. Cancer patients with premature ovarian failure are at increased risk for unpleasant symptoms of menopause and for developing long-term health problems, such as osteoporosis, infertility and possibly cardiovascular disease.

"A cancer diagnosis is a life-changing event for anyone, but young women diagnosed with breast cancer often face a different array of challenges than the typical breast cancer patient who is in their 60s or 70s. Issues such as the long-term effects of treatment, impact on fertility, caring for young children, effect on career and relationships as well as concerns about genetic risk factors add to the heavy weight of a cancer diagnosis," Dr. Moore said. "We recently opened a Young Women's Breast Clinic because we recognize the particular needs of this patient group and want to provide these women with timely and appropriate treatment, consultations and support from the time of their initial diagnosis."

POEMS included 218 premenopausal women worldwide diagnosed with early stage hormone-receptor-negative breast cancer from 2004 to 2011; 135 participants were included in the ovarian failure analysis.Patients were randomized to receive standard chemotherapy with or without goserelin every four weeks for the duration of treatment, beginning at least one week prior to its start. Goserelin works by putting the ovaries in a "resting" state and preventing their normal cycle, making them less vulnerable to the toxic effects of chemotherapy.

In addition to preserving ovarian function, patients who were given goserelin experienced better disease-free survival and overall survival rates than the control group.