Increased post-induction intensification improves outcome in children and adolescents with a markedly elevated white blood cell count (>= 200 x 10(9)/l) with T cell acute lymphoblastic leukaemia but not B cell disease: a report from the Children's Oncology Group

摘要

Children and adolescents presenting with a markedly elevated white blood cell (ME WBC) count (WBC 200x10(9)/l) comprise a unique subset of high-risk patients with acute lymphoblastic leukaemia (ALL). We evaluated the outcomes of the 251 patients (12% of the study population) with ME WBC treated on the Children's Cancer Group-1961 protocol. Patients were evaluated for early response to treatment by bone marrow morphology; those with a rapid early response were randomized to treatment regimens testing longer and stronger post-induction therapy. We found that ME WBC patients have a poorer outcome compared to those patients presenting with a WBC <200x10(9)/l (5-year event-free survival 62% vs. 73%, P=00005). Longer duration of therapy worsened outcome for T cell ME WBC with a trend to poorer outcome in B-ALL ME WBC patients. Augmented therapy benefits T cell ME WBC patients, similar to the entire study cohort, however, there appeared to be no impact on survival for B-ALL ME WBC patients. ME WBC was not a prognostic factor for T cell patients. In patients with high risk features, B lineage disease in association with ME WBC has a negative impact on survival.