Bone Abstracts

Objectives: To determine the national prevalence, management and long term outcomes of patients who develop osteonecrosis after initiation of treatment for acute lymphoblastic leukaemia (ALL).

Methods: The central trials unit for the leukaemia trial UKALL2003 identified patients with reported bone toxicity out of the 3126 patients recruited into the study. Questionnaires were sent to each relevant treatment centre requesting information about each patient, covering demographics, diagnosis, scan results, management and outcomes. Details regarding previously unidentified patients was also requested.

Results: There was a 90% response rate for the 292 patients identified by the central trials unit. Of these 263 patients, 170 patients had radiographically confirmed osteonecrosis, giving a prevalence of 5.4% of patients. Median duration of follow up was 70.5 months, and median time for development of symptoms of osteonecrosis after diagnosis of ALL was 16 months. Age was the most significant risk factor for development of osteonecrosis, with relative risk 17.72 (95% CI 11.28–27.82) and 19.97 (95% CI 12.19–32.71) for those aged 10–15 years and 16–25 years respectively at diagnosis of ALL, compared to those age < 10 years. 85% of patients had multifocal osteonecrosis, with hips and knees most commonly affected. There was significant variation in patient management with regards to cessation of steroids. Bisphosphonate therapy was given to 43 patients (25%), and use was centre specific. Surgery was required in 38% of all patients with osteonecrosis, with 99 surgical procedures reported in 65 patients. 33 patients with osteonecrosis required at least one hip replacement, and 16 patients required more than one joint to be replaced as a result of osteonecrosis. 3.6% of all patients over the age of 10 years at diagnosis of ALL required at least one joint replacement.

Conclusion: This is the largest study of symptomatic osteonecrosis with long term follow up data of childhood ALL in the UK. The considerable morbidity from this condition is clear, with important implications for quality of life. The greatest impact is on those over 10 years of age at diagnosis of ALL, with a surgical intervention required in a large percentage of patients.

Source of funding: Candlelighters charity.

Disclosure: The authors declared no competing interests.