Osteonecrosis in children and adolescents with cancer - an adverse effect of systemic therapy.

Osteonecrosis (ON) is recognised increasingly as a complication of the treatment of cancer in children and adolescents. It is especially prevalent among survivors of acute lymphoblastic leukaemia and non-Hodgkin lymphoma, in whom as many as 1/3 may be affected, likely reflecting the cumulative exposure to glucocorticosteroid therapy. The pathogenesis is complex and includes suppression of bone formation, expansion of the intra-medullary lipocyte compartment and a direct effect on nutrient arteries. Children > or =10 years of age are at particular risk and the disorder is substantially more common in Whites than in Blacks. Genetic predispositions have been identified. ON is often multi-articular and bilateral, affecting weight-bearing joints predominantly. Surgical management options are of concern in young growing subjects, although injection of autologous marrow into affected sites offers promising results. Other novel approaches include the use of anti-resorptive drugs and strategies for prevention, such as with lipid-lowering agents, are being explored.