AbstractThere are limited data pertaining to the prognostic features and optimal therapeutic approach for the 20%–25% of children with lymphoblastic lymphoma (LLy) who have the B‐lymphoblastic subtype. Outcomes are favorable following treatment modeled after acute lymphoblastic leukemia (ALL) regimens, but prognosis is dismal after relapse, and there are no established features for predicting therapy response. Ongoing US and international trials will include the largest cohort of uniformly treated patients with B‐LLy to date, providing an opportunity to define clinical and molecular predictors of relapse and to establish a standard of care for treatment to improve outcomes for this rare pediatric cancer.