Office of Cancer Communications

Building 31,Room 10A24

Bethesda, MD 20892

National Institutes of Health

April 29, 1997

FOR RESPONSE TO INQURIES
NCI Press Office
(301) 496-6641

1. What is the ERT Study?

The ERT Study is a medical study designed to resolve the debate over whether women who have had early stage cancer of the uterus, or endometrial cancer, can safely take estrogen replacement therapy (ER). It is one of many clinical studies sponsored by the National Cancer Institute (NCI) and carried out in medical centers around the country.

2. What is a clinical study?

A clinical study is a study with people that is designed to answer a question relating to the diagnosis, treatment, prevention, or course of a disease. Many kinds of clinical studies are designed to show how a particular approach -- for instance, a promising treatment for a particular kind of cancer or a possible way to improve quality of life for cancer survivors -- affects those who receive it. The study design is specified in a document called a protocol. Clinical studies are also called clinical trials and sometimes simply protocols.

3. What is endometrial cancer?

Endometrial cancer is a form of cancer that originates in the inner lining, or endometrium, of the uterus. Because most cancers of the uterus develop in this inner lining, the terms 'cancer of the uterus,' and 'endometrial cancer' are often used interchangeably.

4. What is estrogen replacement therapy (ERT)?

Estrogen replacement therapy is treatment often prescribed to reduce the discomforts of menopause, such as hot flashes, and to reduce the risk of osteoporosis (fragile bones) and heart disease in women after menopause.

5. Why is ERT after endometrial cancer controversial?

It has been commonly assumed that ERT is not safe for women with a history of endometrial cancer. Many physicians fear that ERT will increase a woman's chances of having the cancer reappear. (Even though the uterus has been removed, the cancer can recur in nearby tissues or spread to other parts of the body.)

There are several reasons for this assumption. One is that estrogen makes cancer cells grow in the laboratory. In addition, there is a good deal of evidence that estrogen, taken without progestin (another female hormone), can contribute to the first development of endometrial cancer.

However, two studies of patients with a history of endometrial cancer have suggested that ERT does not increase the risk of recurrence in selected patients. These findings have created the current debate.

6. What is the evidence linking ERT with the first development of endometrial cancer?

Several large studies have found that women who take estrogen without a progestin have a higher risk of developing endometrial cancer than women who do not use ERT. The risk of estrogen users is estimated to be five to 10 times higher than that of nonusers.

7. What is the evidence that ERT does not cause a recurrence of endometrial cancer?

Two studies have looked at data from groups of endometrial cancer survivors who used ERT. In one study, scientists analyzed data for 221 patients with stage I endometrial cancer, 47 of whom received estrogen for about 26 months after the tumor was removed. This study found that the cancer recurred in 15 percent of the women who did not receive estrogen and in 2 percent of those who did take estrogen.

In the other study, scientists analyzed data from 144 women who had stage I endometrial cancer, including 45 who were at low risk of recurrence and who had taken ERT for about 64 months. None of the estrogen users in this study had the cancer recur.

8. How will the new study be carried out?

Researchers in communities around the country will recruit more than 2,000 women who have had recent surgery for early stage uterine cancer (stages I or II). Participants will be divided randomly (as in a flip of a coin) into two groups. One group will receive pills containing estrogen and the other will receive identical appearing pills that do not contain estrogen (a placebo) for three years. The study is double-blinded -- that is, neither physicians nor patients will know which women are taking the placebo and which are taking estrogen. Women in both groups will have check-ups every six months for three years and then annually for two more years.

9. Who is eligible for this study?

Women with endometrial cancer who have had a total hysterectomy and salpingo-oophorectomy (removal of uterus, ovaries, and fallopian tubes) and found to be at surgical stage IA, IB, IC, IIA or IIB may be eligible. These women must have at least one indication for estrogen replacement therapy, including hot flashes, vaginal atrophy (dryness), increased risk of cardiovascular disease, or increased risk of osteoporosis. Women must have recovered from the effects of the recent surgery and be entered on study within 12 weeks of surgery.

Women not eligible for this study include those with known or suspected breast cancer; those with a history of breast cancer, acute liver disease, or thromboembolic disease (blood clots); or those receiving other forms of hormonal therapy.

10. How can patients enroll in this study?

As in all NCI-sponsored clinical studies, patients are referred by a physician. Any health care provider can enroll patients in this study by contacting physicians who are members of NCI's Community Clinical Oncology Program (CCOP) or Cancer Therapy Evaluation Program (CTEP). For more information, health care providers may contact their nearest participating Gynecologic Oncology Group (GOG) or CCOP institution or call the GOG administrative office at 1-800-225-3053.

Patients may learn more about this study by calling the NCI's Cancer Information Service at 1-800-4-CANCER.

11. How can you learn more about endometrial cancer?

The NCI's PDQ database has information for patients and physicians on diagnosing and treating endometrial cancer. In addition, a booklet for patients, called "What You Need to Know About Cancer of the Uterus," is available from the NCI. Call 1-800-4-CANCER to ask for both the PDQ information and the booklet. PDQ is also accessible through the World Wide Web (go to NCI homepage and click on "Information for Physicians and Health Professionals").

Single, free copies of the pamphlets "Cancer of the Uterus" (APO97) or "Hormone Replacement Therapy" (APO66) are available from The American College of Obstetricians and Gynecologists (ACOG). For each pamphlet, send a stamped, self-addressed, business-size envelope along with the name of the pamphlet to ACOG, Resource Center, 409 12th St., S.W., PO Box 96920, Washington, DC, 20090-6920.

For more information see the Press Release "Estrogen for Survivors of Uterine Cancer? A New Study Will Resolve Debate."