NIH Press Release
National Cancer Institute

Tuesday, Apr. 29, 1997
2:00 P.M. Eastern Time

Caroline McNeil
NCI Press Office
(301) 496-6641
ACOG Office of Public Information
(202) 484-3321
Memorial Sloan-Kettering Cancer Center
(212) 639-3573

Estrogen for Survivors of Uterine Cancer? A New Study Will Resolve Debate

The first large, national study of estrogen replacement therapy (ERT) for women who have had cancer of the uterus will start enrolling patients this summer, researchers announced today at the annual meeting of The American College of Obstetricians and Gynecologists (ACOG) in Las Vegas. The study is designed to resolve the current controversy over the safety of estrogen replacement for survivors of uterine, or endometrial, cancer.

The ERT Study is being sponsored by the National Cancer Institute (NCI) and organized by the Gynecologic Oncology Group (GOG), a program of ACOG. GOG is one of 11 cooperative trial groups -- networks of medical centers that conduct studies jointly to define effective cancer therapy -- sponsored by NCI.

Physicians commonly prescribe estrogen replacement after menopause to prevent osteoporosis and heart disease and to relieve menopausal symptoms, such as hot flashes. But for women with a history of uterine cancer, ERT has long been taboo.

"Many experts have assumed that estrogen could bring about a recurrence of the disease," said GOG Chairman Robert C. Park, M.D. "But right now we have no evidence that ERT causes a recurrence, and we have some evidence that it is safe."

The evidence suggesting that ERT is safe comes from two studies in the late 1980s involving several hundred women who had been diagnosed with cancer of the uterus at an early stage. In both studies, women taking estrogen replacement had no increased risk of recurrence. The findings challenged conventional wisdom and created the current debate.

For the ERT Study, researchers in communities around the country will recruit more than 2,000 women who have had surgery for early stage uterine cancer (stages I or II), said the study's principal investigator, Richard Barakat, M.D., of Memorial Sloan-Kettering Cancer Center in New York City. "We are asking all ACOG members and other physicians to help in completing this important study," Barakat said. ACOG is the national medical organization representing 95 percent of all board-certified obstetrician/gynecologists.

Women who enroll in the study will be divided randomly into two groups. One group will receive pills containing estrogen and the other will receive pills without estrogen (a placebo) for three years. Women in both groups will have check-ups every six months for three years and then annually for two more years.

For physicians who take part in this study, NCI has simplified and streamlined the data collection and reporting requirements, said Edward L. Trimble, M.D., head of the surgery section in NCI's Cancer Therapy Evaluation Program. "This is the first time we will be using simpler requirements," he said. "We hope the ERT Study will eventually serve as a model for other community-based trials that are exploring an important, clinical question such as this."

Cancer of the uterus is the fourth most common cancer in women. This year, an estimated 34,900 women will learn they have the disease. However, most uterine cancers are detected before the tumor has spread outside the uterus, and the five-year survival rate for these early stage patients is over 90 percent. The findings from the ERT Study will help these women and their physicians make informed decisions regarding the use of ERT.

Patients interested in learning more about the ERT Study may call the NCI's Cancer Information Service at 1-800-4-CANCER.

NOTE TO REPORTERS: A backgrounder on this study is available. Call the NCI Press Office at (301) 496-6641.

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