Younger women with early-stage breast cancer who took a drug to suppress their ovaries were more likely to avert early menopause caused by chemotherapy, researchers found.
The treatment, triptorelin, helped patients avoid the permanent loss of their fertility that can be prompted by chemotherapy’s toxic doses, according to research published today in the Journal of the American Medical Association.
Two out of every five women under 40 who undergo chemotherapy for breast cancer lose the ability to conceive children, the researchers said. The use of triptorelin reduced the rate of early menopause by more than 17 percentage points, according to the results of a late-stage clinical trial called Promise-GIM6.
“Because the prevention of early menopause is the essential condition for fertility maintenance, women may more easily accept chemotherapy,” Lucia Del Mastro, an oncologist at the National Institute for Cancer Research in Genoa, Italy, and the study’s lead author, said by e-mail. “This strategy increases the probability of ovarian function maintenance but it doesn’t assure the fertility.”
Triptorelin may stave off menopause and increase the probability of staying fertile by reducing levels of the hormone that stimulates the ovaries. Because chemotherapy targets areas with “rapid cellular turnover,” ovaries that are rendered dormant with the drug may be protected, Del Mastro said.
Doctors diagnose almost 25,000 women younger than 45 with breast cancer every year, wrote Hope Rugo and Mitchell Rosen of the University of California, San Francisco, in an accompanying editorial. Each month of chemotherapy cuts reproductive life by more than a year, the researchers said. Concern that infertility may occur influences treatment decisions in more than a quarter of all cases, the researchers found.
“Young survivors of breast cancer consider premature menopause, sexual dysfunction, and infertility the most distressing aspects of their cancer experience,” they wrote.
The triptorelin strategy could be combined with procedures such as freezing an embryo to further increase the chances that a woman facing chemotherapy may have a child afterward, Del Mastro said.
The scientists evaluated 260 patients in the trial, which began in 2003. Almost 26 percent of the women who received only chemotherapy had early menopause, compared with 7.9 percent of the group receiving both chemotherapy and triptorelin, the researchers found.
About 25 percent of patients treated only with chemotherapy got back some function of their ovaries, compared with 29 percent in the triptorelin group. So far, one woman who was treated with only chemotherapy became pregnant, compared with three who took the drug.
The triptorelin used in the study was supplied by French drugmaker Ipsen SA. The Italian National Institute for Cancer Research funded the trial.