Study of Adults With Low Growth Hormone Who Survived Childhood Cancer Where Treatment Caused Low Bone Density

Treatment of Childhood Cancer Therapy-induced Osteopenia in Growth Hormone Deficient Adult Survivors: Does Bisphosphonate Treatment Improve Bone Mineral Density?

The purpose of this project is to evaluate the hypothesis that bisphosphonate treatment given to growth hormone deficient patients (regardless of current growth hormone replacement therapy status and without changing that status) significantly increases total body bone mineral density during an eighteen month period of treatment combined with calcium and Vitamin D when compared to calcium and Vitamin D treatment alone.

Adult patients with Dexa scan (bone scan) z-scores < -1.0 (meaning low bone density) in at least one site will be selected for randomization. All patients who qualify for randomization will undergo baseline bloodwork for serum bone specific alkaline phosphatase (BSAP) and n-terminal telopeptides of collagen (NTX) levels. Recent bloodwork obtained as part of their ongoing long-term Pediatric Oncology and/or Endocrine clinic follow-up evaluation will be reviewed to exclude any baseline correctable confounding causes of osteopenia (low bone density). All women of childbearing potential will have a pregnancy test.

For those patients already on growth hormone replacement therapy, growth hormone will be administered as per standard of care, with standard dose ranges adjusted based upon IGF-1(Insulin like growth factor) monitoring. Those patients not currently receiving growth hormone replacement therapy will not be placed on therapy as a part of this study. Patients on and off growth hormone replacement therapy will be randomized in a block design to the two treatment arms to assure equal numbers in each treatment arm. The bisphosphonate to be utilized will be provided to the Arm II patients at no charge. All Arm II patients will receive the same bisphosphonate regimen, Risedronate 35 mg per oral once weekly for 18 months. All patients on arms I and II will also receive Vitamin D (400 IU p.o. daily) and calcium carbonate (500 mg p.o. twice daily) free of charge for eighteen months.

Inclusion Criteria:

• Growth hormone deficiency as a complication of treatment for pediatric malignancy
• Dexa (bone densitometry)with z-scores of < -1.0 in at least one site

Exclusion Criteria:

• Dexa (bone densitometry)with z-scores < -1.0 in at least one site
• Subjects <18 years old
• Pregnant or lactating patients
• Any contraindication for or unwillingness to consider bisphosphonate treatment
• Inability or unwillingness to undergo bone density evaluation
• Other correctable causes of decreased bone mineral density