Overall survival of children and adolescents with mature B cell non‐Hodgkin lymphoma who had refractory or relapsed disease during or after treatment with FAB / LMB 96: A report from the FAB / LMB 96 study group

Summary We determined the risk factors associated with poor survival in children and adolescents with de novo mature B cell non‐Hodgkin lymphoma (B‐ NHL ) who had refractory or relapsed disease during or after the French‐American‐British mature lymphoma B ( FAB / LMB ) 96 multi‐agent chemotherapy. Among the 1 111 registered on study, 104 patients (9·4%) had refractory disease or disease relapse after first complete remission. Among these 104 patients, 28 (27%) patients had refractory disease and 76 (73%) had relapsed disease. The estimated 1‐ and 2‐year overall survival ( OS ) (95% confidence interval) was 31·5% (23·3–41·0%) and 22·3% (15·3–31·4%), respectively. Prognostic analysis of OS using a Cox multivariate model showed that factors independently associated with OS included lactate dehydrogenase ≥2 upper normal limit [hazard ratio ( HR ) = 2·86 (1·57–5·2), P  = 0·0006]; time to failure (>6 months) [ HR  = 0·59 (0·36–0·97), P  = 0·038]; and failure in bone marrow [ HR  = 2·78 (1·65–4·68), P  = 0·0001]. New therapeutic strategies are required to significantly reduce refractory disease and disease relapse in patients with newly diagnosed mature B‐ NHL and, more importantly, there is a critical need to develop novel retrieval approaches in patients with chemotherapy‐resistant disease.