The safety and efficacy of CAR T-cell therapy are unknown in pediatric and adolescent patients with relapsed or refractory primary mediastinal large B-cell lymphoma (R/R PMBCL) which is associated with dismal prognosis. Here, we present a case report of a 16-year-old patient with R/R PMBCL treated with lisocabtagene maraleucel including correlative studies. Patient achieved complete response at 6 months without cytokine release syndrome and immune effector cell-associated neurotoxicity …