Fingernails in Evaluating Bone Health in Postmenopausal Women With Breast Cancer Undergoing Hormone Therapy on Clinical Trial IBCSG-1-98

You may be eligible if

• DISEASE CHARACTERISTICS:
• Enrolled on protocol IBCSG-1-98
• * Currently receiving (i.e., have not yet completed) 5 years of treatment with tamoxifen or letrozole and expected to receive ≥ 6 months of additional treatment on protocol IBCSG-1-98
• No recurrent breast cancer or second primary cancer
• No known bone disease (including osteomalacia or osteogenesis imperfecta)
• Hormone receptor status
• * Estrogen and/or progesterone receptor positive tumor
• PATIENT CHARACTERISTICS:
• Female
• Postmenopausal
• No uncontrolled thyroid or parathyroid disease, Cushing's disease, or other pituitary diseases
• No malabsorption syndrome or clinically relevant vitamin D deficiency
• PRIOR CONCURRENT THERAPY:
• See Disease Characteristics
• More than 1 year since prior and no concurrent anticonvulsants
• More than 6 months since prior and no concurrent corticosteroids at doses \> the equivalent of 5 mg/day of prednisone for \> 2 weeks total
• No prior or concurrent sodium fluoride at daily doses ≥ 5 mg/day for \> 1 month
• More than 12 months since prior and no concurrent anabolic steroids
• More than 6 months since any prior drug for the prevention of osteoporosis (excluding calcium or cholecalciferol \[vitamin D\])
• Concurrent warfarin allowed provided duration of treatment is no more than 4 weeks