Drugs that affect the ovaries may help treat some women with hormone-sensitive breast cancer, researchers report in The Lancet.
They included Jack Cuzick, PhD, who works in London at Cancer Research U.K.
Cuzick and colleagues focused on a class of drugs called LHRH agonists, which can reduce the amount of estrogen produced by the ovaries. Examples of LHRH agonists include Zoladex and Lupron.
About two-thirds of women with breast cancer have estrogen-sensitive breast tumors, meaning that those tumors are fueled by estrogen. Curbing estrogen helps fight those cancers.
Breast cancer drugs that target estrogen include tamoxifen and aromatase inhibitors. Those drugs work differently from LHRH agonists.
Cuzick's team pooled data from 16 studies of about 11,900 premenopausal women with hormone-sensitive breast cancer.
Relatively few women only took LHRH agonists. Others just got chemotherapy and/or tamoxifen. Still others got LHRH agonists in addition to chemotherapy and/or tamoxifen.
Cuzick's team found that LHRH agonists, taken alone, were comparable to chemotherapy in reducing the odds of breast cancer recurrence or death from breast cancer recurrence.
Adding LHRH agonists to chemotherapy and/or tamoxifen lowered recurrence by nearly 13 percent and lowered death after recurrence by about 15 percent.
Those effects were strongest in women less than 40 years old.
However, it's too soon to recommend the addition of LHRH agonists for all premenopausal women with hormone-sensitive breast cancer, according to an editorial published in The Lancet.
"In women with higher-risk disease, chemotherapy followed by tamoxifen should still be the standard approach, with the addition of an LHRH analogue [agonist] a reasonable consideration for those who remain premenopausal," write the editorialists.
They included Nicholas Wilcken, MBBS, PhD, FRACP, who works in Sydney, Australia, in the medical oncology department of Westmead and Nepean Hospitals and the University of Sydney.
The Lancet notes that Cuzick is a statistical consultant for the drug company AstraZeneca, which makes Zoladex, but that work is unrelated to the drugs in this study.
This article was reviewed by Brunilda Nazario, MD.
SOURCES: Cuzick, J. The Lancet, May 19, 2007; vol 369: pp 1711-1723. WebMD Medical Reference: "Breast Cancer: Hormone Therapy." Wilcken, N. The Lancet, May 19, 2007; vol 369: pp 1668-1670. News release, The Lancet.