Indole-3-Carbinol in Preventing Breast Cancer in Nonsmoking Women Who Are at High Risk For Breast Cancer

DISEASE CHARACTERISTICS:

* Women at high risk for breast cancer, defined by at least 1 of the following criteria:

  * Projected 5-year probability of invasive breast cancer at least 1.66%, as determined by the Breast Cancer Risk Assessment Tool
  * Prior node-negative breast cancer
  * Prior biopsy indicating atypical lobular or ductal hyperplasia or carcinoma in situ
  * Age 60 and over
* Non-smoker confirmed by urine cotinine test
* No concurrent breast cancer
* Hormone receptor status:

  * Not specified

PATIENT CHARACTERISTICS:

Age:

* 18 to 70

Sex:

* Female

Menopausal status:

* Premenopausal (regular menstrual cycles of 24-36 days within the past 6 months) OR
* Postmenopausal (no menstrual cycle for at least 6 months)

Performance status:

* Not specified

Life expectancy:

* At least 1 year

Hematopoietic:

* Absolute granulocyte count greater than 1,500/mm\^3
* Hemoglobin greater than 10 g/dL

Hepatic:

* Bilirubin less than 1.8 mg/dL
* Aspartate aminotransferase (AST) and Alanine transaminase (ALT) less than 110 U/L
* Alkaline phosphatase less than 300 U/L
* Albumin greater than 3 g/dL

Renal:

* Creatinine less than 2.0 mg/dL

Cardiovascular:

* No acute or unstable cardiovascular condition based on electrocardiogram

Other:

* Mild seasonal allergies allowed
* No serious or life-threatening drug allergies
* No other serious intolerances or allergies
* No more than 20% above or below ideal body weight
* No acute or unstable medical condition by physical examination or laboratory tests
* No chronic headaches, dysphoria, fatigue, dizziness, blurred vision, insomnia, rhinorrhea, nausea, vomiting, abdominal pain, diarrhea, constipation, or similar conditions
* No serious illness requiring chronic drug therapy
* No active malignancy
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective barrier contraception 1 month before, during, and for 1 month after study

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* Not specified

Chemotherapy:

* No prior chemotherapy

Endocrine therapy:

* At least 2 months since prior hormonal therapy as contraception or hormone replacement therapy (HRT)
* No concurrent sex hormones as contraception for premenopausal women
* No concurrent HRT for postmenopausal women

Radiotherapy:

* Not specified

Surgery:

* Not specified

Other:

* At least 6 months since prior investigational drugs
* At least 1 month since prior weekly consumption of more than 3 medium servings (half cup each) of cruciferous vegetables
* No concurrent vegetarian diet or weekly consumption of more than 3 medium servings (half cup each) of cruciferous vegetables
* No continuous supplement intake
* No recent change in medications or dosage of medications