Long-Term Bone Quality in Women With Breast Cancer (A Companion Study to S0307)

OBJECTIVES:

• To assess if long-term high-dose bisphosphonates alter bone quality as measured by change in the histomorphometry of bone biopsies after tetracycline hydrochloride labeling to calculate eroded and osteoid surfaces, mineralization surface, bone formation rate, wall width, and activation frequency.
• To assess if long-term high-dose bisphosphonates alter bone quality as measured by change in the backscattered electron imaging of bone to measure average mineralization density as well as distribution of density values.
• To assess if long-term high-dose bisphosphonates alter bone quality as measured by change in the micro-computed tomography of bone biopsy specimens to measure bone structure, including bone volume, connectivity, trabecular width, and cortical width.
• To assess if long-term high-dose bisphosphonates alter bone quality as measured by change in the biomechanical testing of bone biopsy samples loaded in compression to measure stress-strain relationships, including Young's modulus, yield point, ultimate strain, and work to failure (toughness).
• To characterize bone using classical, non-invasive techniques (i.e., measurement of bone mineral density of spine and hip using dual energy x-ray absorptiometry and analysis of serum biochemical markers of bone formation [i.e., bone specific alkaline phosphatase] and resorption [i.e., N-telopeptide]) after long-term, high-dose bisphosphonates.

OUTLINE: This is a multicenter study.

At baseline (prior to initiating bisphosphonate therapy on SWOG-S0307), patients receive oral tetracycline hydrochloride twice daily on days 1 and 2 and oral demeclocycline hydrochloride twice daily on days 11 and 12. Patients undergo a tetracycline hydrochloride-labeled bone biopsy from the anterior ilium on day 14. At 36 months (for patients who have completed bisphosphonate therapy) or after 30 months of concurrent bisphosphonate therapy, patients receive oral demeclocycline twice daily on days 1 and 2 and oral tetracycline hydrochloride twice daily on days 11 and 12. Patients undergo a demeclocycline hydrochloride-labeled bone biopsy from the anterior ilium on day 14.

Patients undergo dual energy x-ray absorptiometry measurements of the hip and spine at the time of biopsy or within the next 10 weeks. Blood samples are collected for analysis of bone specific alkaline phosphatase and N-telopeptide before and after treatment on the clinical trial.