Predicting relapse in acute lymphoblastic leukemia

Outcomes in adult and pediatric patients with acute lymphoblastic leukemia (ALL) have improved over successive generations due to rigorously conducted clinical trials and incorporation of novel therapeutic agents. Despite these advances, approximately 20% of high-risk pediatric patients and 50% of adults with ALL will fail to achieve long-term remission with frontline chemotherapy protocols, mostly due to relapse. The ability to predict which patients with ALL are more likely to relapse allows for early intensification of therapy and/or incorporation of novel immunotherapies with the goal of relapse prevention. In this review, we outline the most robust clinical predictors of relapse in ALL with a focus on measurable residual disease (MRD) and genomics. We also discuss application of these prognostic tools in different clinical settings including frontline treatment, pre-/post-allogeneic stem cell transplant, and pre-/post-Chimeric Antigen Receptor T-cell therapy.