Kaplan-Meier curves demonstrating the effect of blast glutathione on survival in childhood ALL.

Event-free survival is shown in panel A and overall survival in panel B. The patients were stratified according to lymphoblast glutathione levels. A high level (solid line) is defined as being above the median blast glutathione concentration for this cohort of patients (6.54 nmol/mg cytosolic protein) and a low level (dashed line) as being below the median value. In both cases, the difference between the curves is statistically significant (P = .018 for event-free survival, P = .04 for overall survival by log-rank analysis).