RATIONALE: Tamoxifen may be able to increase bone density and decrease cholesterol in women who are undergoing chemotherapy for breast cancer.

PURPOSE: Clinical trial to study the effectiveness of tamoxifen in preventing bone loss and heart disease caused by chemotherapy treatment in premenopausal women who have stage I or stage II breast cancer.

OBJECTIVES:

• Compare the bone density in the femoral neck and lumbar spine and cholesterol levels in premenopausal women with stage I or II breast cancer treated with adjuvant chemotherapy with or without tamoxifen.
• Collect information regarding breast cancer risk factors, treatment, pathology, diet, activity levels, weight, and smoking in these patients.

OUTLINE: Patients are stratified according to type of treatment (adjuvant chemotherapy plus tamoxifen vs adjuvant chemotherapy alone).

Patients receive adjuvant chemotherapy with or without oral tamoxifen at the discretion of the treating physician.

Prior to starting chemotherapy, patients undergo blood draw to measure baseline levels of follicle-stimulating hormone, estradiol, total cholesterol, high-density lipoproteins, and low-density lipoproteins. Patients undergo baseline bone densitometry of the femoral neck and lumbar spine to assess bone density prior to starting chemotherapy or within 30 days of the first drug treatment. Laboratory studies and bone densitometry are repeated at years 1 and 2. A comparison is made between the study findings at baseline and at years 1 and 2.

PROJECTED ACCRUAL: A total of 80 patients (40 per stratum) will be accrued for this study.

DISEASE CHARACTERISTICS:

• Histologically proven stage I or II breast cancer

• Must be scheduled to receive adjuvant chemotherapy with or without tamoxifen

• Hormone receptor status:

  • Not specified

PATIENT CHARACTERISTICS:

Age:

• 35 to 50

Sex:

• Female

Menopausal status:

• Premenopausal by follicle-stimulating hormone and estradiol levels

Performance status:

• Not specified

Life expectancy:

• Not specified

Hematopoietic:

• Not specified

Hepatic:

• Not specified

Renal:

• Not specified

Other:

• Not pregnant

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• See Disease Characteristics

Endocrine therapy:

• See Disease characteristics

Radiotherapy:

• Not specified

Surgery:

• Not specified

Patients with stage I or II breast cancer currently undergoing treatment with either chemotherapy or tamoxifen.