Prognostic factors and outcome for children after second central nervous system relapse of acute lymphoblastic leukaemia

The Medical Research Council acute lymphoblastic leukaemia trials (UKALL X and XI) recruited 3702 children with ALL between January 1985 and March 1997. Seventy‐nine children had central nervous system (CNS) involvement in their first two relapses. Fourteen children survived at a median follow‐up of 22 months from second relapse; seven (9%) in third remission, two in later remissions and five with disease. Factors predictive of survival from second relapse were site (isolated CNS was better than combined CNS, P = 0·02) and time from diagnosis to second CNS relapse (longer time was better, P = 0·004). Prognosis after second CNS relapse is extremely poor, and palliative therapy is appropriate.