Letrozole in Preventing Breast Cancer in Postmenopausal Women Who Are at Increased Risk for Breast Cancer Due to High Breast Density

You may be eligible if

• DISEASE CHARACTERISTICS:
• At increased risk for the development or recurrence of breast cancer, as defined by 1 of the following:
• * Baseline mammogram indicating mammographic density occupying ≥ 25% (grade 4/6, 5/6, or 6/6) of the breast tissue
• * No suspicion of breast cancer, unless subsequently ruled out
• * Prior ductal carcinoma in situ (DCIS)
• * Untreated disease OR \> 6 months since completion of adjuvant endocrine therapy
• * Receptor status of lesion is not required
• * Prior invasive breast cancer
• * Breast cancer must have been surgically removed at time of original diagnosis with no evidence of metastases
• No clinical evidence of breast cancer
• Acceptable quality dual-energy x-ray absorptiometry (DEXA) of the L2-L4 postero-anterior (PA) spine and hip performed within past 6 months
• * Bone mass density T-score of either PA spine or hip must be ≥ 2.0 SD below the mean peak bone mass in young normal woman
• Stable chronic leukemia allowed
• Hormone receptor status:
• * Hormone receptor-negative, -positive, or -equivocal tumor
• PATIENT CHARACTERISTICS:
• Age
• Postmenopausal
• Sex
• Female
• Menopausal status
• Postmenopausal, as defined by 1 of the following:
• * Over 55 years of age with spontaneous cessation of menses for ≥ 1 year
• * 55 years of age and under with spontaneous cessation of menses for ≤ 1 year, but amenorrheic (e.g., spontaneous or secondary to hysterectomy) AND follicle-stimulating hormone level \> 34.4 IU/L
• * Bilateral oophorectomy
• Performance status
• Not specified
• Life expectancy
• Not specified
• Hematopoietic
• Not specified
• Hepatic
• Not specified
• Renal
• Not specified
• Cardiovascular
• No recent unstable myocardial infarction
• No prior stroke
• No high blood pressure
• No other uncontrolled cardiovascular disease
• Other
• Other prior malignancies without metastatic disease allowed
• Willing and able to complete quality of life questionnaires in either English or French
• No uncontrolled metabolic or endocrine disease
• No malabsorption syndrome
• PRIOR CONCURRENT THERAPY:
• Biologic therapy
• No concurrent immunotherapy
• Chemotherapy
• No concurrent chemotherapy
• Endocrine therapy
• See Disease Characteristics
• At least 3 months since prior and no concurrent hormone replacement therapy or raloxifene
• At least 6 months since prior tamoxifen
• No concurrent steroid therapy
• No concurrent selective estrogen-receptor modulators
• No other concurrent endocrine or hormonal therapy
• Radiotherapy
• Not specified
• Surgery
• See Disease Characteristics