07/15/08 - Osteonecrosis uncommon in childhood cancer survivors

NEW YORK (Reuters Health) - Although osteonecrosis is rare in adult survivors of childhood cancer, they appear to be at significantly increased risk compared to their siblings, according to North American researchers.

In the June 20th issue of the Journal of Clinical Oncology, Dr. Nina S. Kadan-Lottick of Yale University School of Medicine, New Haven, Connecticut and colleagues observe that osteonecrosis is exceedingly rare in the general population but can be a serious complication of childhood cancer therapy.

To gain further information on the matter, the researchers examined data on 9261 5-year survivors of childhood cancer diagnosed between 1970 and 1986. Their self-reported rate of osteonecrosis was compared with that in 2872 of their randomly chosen siblings.

Overall, 52 survivors reported osteonecrosis in 78 joints giving a 20-year cumulative incidence of 0.43%. Compared to their siblings, after adjustment for age and sex, this yielded a rate ratio of 6.2.

The rate ratio was greatest among survivors of stem-cell transplantation for chronic myelogenous leukemia (93.1), acute myelogenous leukemia (66.5) and acute lymphoblastic leukemia (26.9).

Factors independently associated with osteonecrosis included being older at diagnosis, having had treatment in an earlier era, and being exposed to dexamethasone and to radiation, both gonadal and nongonadal.

Given these findings, the researchers conclude that "medical providers caring for cancer survivors should question their patients about pain and mobility problems in joints and monitor for progression and disability."