Doctors may have found a way to help young breast cancer patients avoid infertility caused by chemotherapy by giving them a drug to temporarily shut down their ovaries, researchers announced on Friday.
The study, presented at a meeting of the American Society of Clinical Oncology in Chicago, showed that women who received AstraZeneca's drug goserelin along with chemotherapy were 64 percent less likely to develop premature menopause than women who had chemotherapy alone. They were also more likely to have successful pregnancies, and the treatment appeared to improve survival.
Permanent menopause is a common side effect for younger women undergoing chemotherapy for breast cancer.
About a quarter of breast cancers occur in women under 50, affecting some 40,000 to 50,000 women each year. Unlike natural menopause, which occurs gradually, chemotherapy can suddenly throw a woman into full-blown menopause. In about half of these women, this condition is permanent, eliminating the chance for a future pregnancy.
"This is the first time anything has been shown to prevent this," Dr. Kathy Albain of Loyola University Medical Center, a senior author of the study, told Reuters. "I think these findings are going to change our clinical practice."
"They're really exciting findings" that could help thousands of women each year in the United States alone, the study's leader, Dr. Halle Moore of the Cleveland Clinic, told The Associated Press.
Goserelin closely resembles a hormone normally released by the hypothalamus. It is already approved for prostate and advanced breast cancers. In premenopausal women, the drug temporarily shuts down the ovaries, essentially putting them on hold during chemotherapy.
"It's basically a temporary menopause to prevent permanent menopause," Moore explained.
Doctors think that active ovaries are more susceptible to chemo damage and that making them dormant might help shield them from harm.
Out of 257 patients in the trial, half received chemotherapy alone and half got chemotherapy plus monthly injections of goserelin. Its main side effects are menopause symptoms – hot flashes and vaginal dryness.
After two years, 8 percent of women in the goserelin group had organ failure versus 22 percent in the standard chemotherapy arm. Among those getting goserelin, 22 women, or 21 percent, got pregnant compared with 12 women, or 11 percent, receiving chemotherapy alone.
The results also suggested women who received goserelin were 50 percent more likely to be alive four years after starting treatment compared with those receiving the standard therapy.
The goserelin approach worked for study participant Christy Wolford, who was treated at the University of Texas MD Anderson Cancer Center in Houston. She was only 28 when her breast cancer was found, and she wanted more children besides the 5-month-old daughter she had at the time. Her ovaries were suppressed during cancer treatment, and she has had three boys since it ended in 2006.
"I'm the poster child" for the study, she told AP.