Bone mineral density deficits in pediatric patients treated for sarcoma.

Background: Children treated for sarcoma are at risk of treatment-associated deficits in bone mineral density (BMD). We investigated the severity of risk factors for BMD deficits in this patient population.

Procedure: Using signed-rank test and logistic regression analysis, we retrospectively analyzed the relation of treatment variables and other potential risk factors to BMD (using quantitative computed tomography (QCT)) of 99 patients treated for pediatric sarcoma who had completed therapy at least 1 year previously.

Results: The study group (38% rhabdomyosarcoma (RMS), 25% osteosarcoma (OS), 24% Ewing-family tumors, and 12% non-rhabdomyosarcoma soft-tissue sarcoma (NRSTS)) represented 22% of the sarcoma survivors treated between 1982 and 2003 who remained in follow-up at St. Jude. These patients underwent QCT between July 1, 1997 and February 5, 2003. Their median age was 8.7 years (range, 0.2-21.3 years) at diagnosis and 17.4 years (range, 3.3-30.2 years) at the time of BMD measurement; 58% were male and 82% Caucasian. Median BMD Z-score was -0.75 (range, -3.33-3.02), and median BMD was 168.0 mg/cc (range, 89.2-264.8 mg/cc). Risk of BMD deficit increased significantly with younger age at diagnosis (P = 0.044) and higher cumulative cyclophosphamide dose (P = 0.007). Patients with lower extremity primary disease had a significantly lower risk of BMD deficits than others. We found no association between BMD and body habitus, primary disease, lifestyle factors, or endocrinopathy.

Conclusion: A significant subset of sarcoma survivors are at risk of BMD deficits warranting prospective study of BMD to verify our results and refine risk factors contributing to BMD deficits.