IRB Number:

1911-03

Trial Status:

Open for Enrollment

Phase: III

Why is this study being done?

This research study is being done to:

• see if ovarian function suppression [OFS] plus giving tamoxifen or exemestane is better at stopping the return of breast cancer than just giving tamoxifen in pre-menopausal women. Ovarian function suppression [OFS] shuts down the ovaries and stops them from making hormones such as estrogen.


• see if a newer hormone drug called exemestane plus OFS is better than tamoxifen plus OFS.


• see what are the good and bad side effects of the treatment.


• see how the treatment affects how well the patient feels.
• see if there are any effects (good and bad) that happen after treatment has stopped.

Who is Eligible to Participate in the Study?

Premenopausal women who have been diagnosed with breast cancer may be eligible to participate in this research study.

What is Involved With this Study?

The International Breast Cancer Study Group (IBCSG) is coordinating this study. Patients will enter into this study as part of the Cancer Trials Support Unit (CTSU), a project sponsored by the National Cancer Institute (NCI) to provide doctors and patients with greater access to NCI-sponsored phase III clinical trials.

Treatment with hormones has been shown to help prevent breast cancers from coming back after they have been taken out by surgery, if the breast cancer has hormone receptors. The hormone generally used is tamoxifen, and it is usually given for five years. It has also been shown that shutting down the ovaries helps stop breast cancers from coming back in women who are premenopausal.

No one knows which treatment is best for the patient. The treatment the patient will get will be decided by chance (like the flip of a coin). This procedure is called randomization. Which group the patient is put in is done by a computer. Chances of getting tamoxifen, tamoxifen plus OFS, or exemestane plus OFS are equal (1/3 chance of getting any one of the treatments). Neither the patient nor the study doctor will choose which group a patient will be in. If the study doctor recommends that a patient get chemotherapy first, patients will be randomized to one of the groups within six months after having stopped getting chemotherapy.

How long will the Study run?

Patients will get the hormone treatment for 5 years unless the cancer comes back. However, patients will be followed for rest of life to see if the cancer ever comes back.

Who can I Contact for Additional Information on this Trial?

Complete Request Form for Cancer Clinical Trial Information at Mayo Clinic or
For more information about this study or other clinical trial options, please contact our Mayo Clinic Cancer Center Clinical Trials Referral Office.

• Patients living within the United States, call 507-538-7623, or e-mail cancerclinicaltrials@mayo.edu


• Patients living outside the United States may call our International Office at 507-284-8884, or e-mail intl.mcr@mayo.edu.

What is/are the Locations of this Clinical Trial?

• Rochester, MN

Last updated: 05/07/2008