Double-Blind Randomized Trial of Tamoxifen Versus Placebo in Patients With Node Positive or High Risk Node Negative Breast Cancer Who Have Completed CMF, CEF, or AC Adjuvant Chemotherapy

OBJECTIVES: I. Compare the duration of overall survival and disease-free survival in premenopausal women with operable, high risk node negative or axillary node-positive breast cancer who have undergone complete surgical resection of all known disease by means of total or partial mastectomy, and have received standard adjuvant chemotherapy with cyclophosphamide, methotrexate, and fluorouracil (CMF), cyclophosphamide, epirubicin, and fluorouracil (CEF), or doxorubicin and cyclophosphamide (AC) followed by either daily tamoxifen for 5 years or placebo. II. Compare the short- and long-term toxicity in patients receiving tamoxifen versus placebo. III. Monitor follicle-stimulating hormone, luteinizing hormone, and estradiol levels, and determine whether overall survival and disease-free survival are affected by hormonal or menopausal status during or at completion of adjuvant chemotherapy or during or after tamoxifen or placebo treatment in these patients.

OUTLINE: This is a randomized, double blind study. Patients are stratified by adjuvant chemotherapy regimen (cyclophosphamide, epirubicin, and fluorouracil vs cyclophosphamide, methotrexate, and fluorouracil vs cyclophosphamide and doxorubicin), hormone receptor status (ER and/or PR positive vs ER and PR negative), number of positive nodes (1-3 vs 4-9 vs 10 or more), and participating institution. Patients receive one of three regimens of adjuvant chemotherapy at the discretion of the investigator. Regimen A: Patients receive oral cyclophosphamide on days 1-14 and epirubicin IV and fluorouracil IV on days 1 and 8. Courses repeat every 28 days for a total of 6 courses. Following chemotherapy, lumpectomy patients receive local radiotherapy daily for 5 weeks. Regimen B: Patients receive oral cyclophosphamide on days 1-14 or cyclophosphamide IV on day 1 and 8, methotrexate on days 1 and 8, and fluorouracil IV on days 1 and 8. Courses repeat every 28 days for a total of 6 courses. Concurrent with or following chemotherapy, lumpectomy patients receive local radiotherapy daily for 5 weeks. Regimen C: Patients receive doxorubicin IV and cyclophosphamide IV every 21 days for a total of 4 courses. Following chemotherapy, lumpectomy patients receive local radiotherapy daily for 5 weeks. Patients are then randomized to receive either oral tamoxifen or a placebo once daily for 5 years, beginning within 6 weeks of completion of chemotherapy. Treatment continues in the absence of disease progression or unacceptable toxicity. Patients are followed for survival.

PROJECTED ACCRUAL: A total of 800 patients will be accrued for this study over 4 years.