FRIDAY, May 18, 2007 (HealthDay News) -- A new form of hormone therapy could help younger women battling a specific type of breast cancer, British researchers report.
Drugs called luteinising-hormone-releasing hormone (LHRH) agonists, appear to be effective alone or combined with other treatments in fighting off hormone receptor-positive breast cancer, researchers suggest. This breast cancer subtype is spurred into growth by the presence of estrogen.
"This is an important finding for the subgroup of women who develop estrogen receptor-positive breast cancer before menopause," said Dr. Michael Thun, the head of epidemiological research at the American Cancer Society. He was not involved in the study.
Luteinising hormone is made in the pituitary gland and stimulates ovulation and the production of estrogen. LHRH agonists copy the action of luteinising hormone and block the signal for making estrogen, which can stimulate the growth of breast cancer, according to the report in the May 19 issue of The Lancet.
In the study, Jack Cuzick, a professor from the University of London, and colleagues collected data from 16 trials on almost 12,000 premenopausal women who had developed early-stage breast cancer. "About 25 percent of breast cancer cases occur in women under age 50," Thun noted.
The team found that LHRH agonists were just as effective as chemotherapy for women with hormone receptor-positive breast cancer.
When LHRH agonists were combined with chemotherapy or tamoxifen, the combined treatment reduced a woman's risk for breast cancer recurrence by almost 13 percent and her risk of death after recurrence by 15 percent.
However, the combined treatments only benefited women under 40, the researchers found. LHRH agonists were not effective among women with hormone receptor-negative tumors, according to the report.
"The results of our analysis show that LHRH agonists provide an effective additional class of agents for the treatment of premenopausal women with hormone-sensitive breast cancer," the team concluded.
Treating breast cancer is increasingly done by combining treatments, Thun said. Doctors may want to now consider adding LHRH to chemotherapy or tamoxifen, he said.
"This is definitely an approach that might be used," Thun said. "The challenge is to determine what the benefit of LHRH is, particularly in the presence of chemotherapy and tamoxifen."
More information
For more information on breast cancer, visit the U.S. National Cancer Institute.
