Introduction The introduction of CAR-T cell treatment for relapsed/refractory (r/r) mantle cell lymphoma improved survival rates of these patients. Along with its introduction in clinical routine, long-term events after CAR-T cell treatment are increasingly emerging.Case Presentation We report the case of a patient developing acute erythroid leukemia with biallelic TP53 inactivation occurring 26 months after CAR-T therapy with brexucabtagene autoleucel (brexu-cel) for r/r mantle cell lymphoma. The patient presented with a healthy bone marrow prior to lymphoma treatments.Discussion Secondary malignancies seem more frequent after CAR-T therapies. More studies are needed to assess potential long-term toxicities of CAR-T cell therapies including the frequency of secondary myeloid malignancies.
