Beyond Bone Mineral Density: The Impact of Childhood Cancer and Its Treatment on Bone Structure and Strength.

Abstract

The spectrum of bone morbidity in childhood cancer survivors (CCS) is broad and extends beyond "low bone mineral density" to structural damage including fracture-induced vertebral deformity, and joint collapse due to osteonecrosis or slipped capital femoral epiphysis. In addition, short stature, scoliosis, leg length discrepancy, and vertebral deformity can arise from critical interference with growth plate activity. In some cases, insufficient residual growth potential or irreversible growth plate damage can lead to permanent structural deformity, leaving the patient with chronic functional limitations. In this chapter, we describe the clinical manifestations, natural history, and risk factors for cancer-related bone morbidity, approaches to monitoring and diagnosis, and the (paucity of) data available on prevention and treatment measures. In so doing, we unveil important biological principles about the potential for the pediatric skeleton to recover from bone morbidity, obviating the need for treatment, versus permanent structural damage that can negatively impact quality of life over the long-term. These observations, in turn, illuminate the unmet needs that drive future research to improve musculoskeletal strength and mobility in this setting.