Osteonecrosis in patients with acute lymphoblastic leukaemia: a national questionnaire study

Objectives: To establish prevalence, management and long-term outcomes of osteonecrosis (ON) in young people diagnosed with acute lymphoblastic leukaemia (ALL) between 2003 and 2011. Design, setting, participants: This study assessed ON in 3113 patients aged 1–24 years who participated in the UK national leukaemia study UKALL 2003. UKALL 2003 recruited patients in 40 UK hospitals between 2003 and 2011 and included patients between ages 1 and 25 diagnosed with ALL. Results: 170 patients were diagnosed with ON, giving a prevalence of 5.5%. The multivariable analysis showed that the risk of ON was highest for children aged between 10 and 20 years (ages 10–15 years, OR 23.7, 95% CI 14.8 to 38.0; ages 16–20 years, OR 22.5, 95% CI 12.7 to 39.8, compared with age <10 years). Among ethnic groups, Asian patients had the highest risk of ON (OR 1.92, 95% CI 1.1 to 3.6, compared with White patients). Eighty-five per cent of patients with ON had multifocal ON. Thirty-eight per cent of patients with ON required surgery and 19% of patients with ON required a hip replacement. Fifteen per cent of patients who had surgery still describe significant disability or use of a wheelchair. Conclusions: ON has considerable morbidity for patients being treated for ALL, with a high burden of surgery. Age and ethnicity were found to be the most significant risk factors for development of ON, with Asian patients and patients aged 10–20 years at diagnosis of ALL at greatest risk. These results will help risk stratify patients at diagnosis of ALL, and help tailor future prospective studies in this area.