Abstract
In the modern era, classification of neoplasms not only depends on immunomorphological features but also on specific disease-defining genetic events. Translocations/rearrangements of MYC/8q24 locus combined with BCL-2 or BCL6 translocations (double/triple hit) are considered hallmarks of high-grade B-cell lymphoma (HGBL), a type of aggressive mature B-cell lymphoma. When cases with immature immunophenotypes present these rearrangements, diagnosis becomes very difficult. We herein report an unusual case of an aggressive B-cell lymphoma/leukemia that presented with immature morphology and immunophenotype with triple hit gene rearrangements. This case highlights the difficulty in classifying and appropriately treating these patients. The novel aspect is the treatment and outcome with chimeric antigen receptor or CAR T-cell therapy.