End of induction MRD assessment based early treatment intensification with novel agents in ETP-ALL- may be the way forward.

TO THE EDITOR: Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) arises from early thymic progenitor cells that migrate from the bone marrow to the thymus and have the potential to differentiate into myeloid/dendritic or T cells. Gene expression profiling has revealed that ETP cells share similarities with hematopoietic stem cells and myeloid progenitor cells. ETP leukemic cells do not express CD1a, CD8, and CD5 (negative to dim). Instead, these cells express ≥1 stem cell/myeloid markers. However, in addition to other ETP-ALL diagnostic criteria, near-ETP-ALL usually shows brighter CD5 [1]. In the literature, the data on ETP-ALL varies markedly, ranging from outcomes poorer than those of other T-ALL to comparable outcomes, with complete remission (CR) rates ranging from 70% to more than 90% [2-5]. Combination chemotherapy is the mainstay treatment. ETP-ALL represents a high-risk subtype of ALL. These outcomes highlight the need for alternative therapeutic approaches that are prognosis-based, and ideally, aiming for minimal residual disease (MRD)negative remission, which may help in preventing relapse. Here, we present the results of a retrospective study on ETP/near-ETP-ALL in the Department of Hemato-Oncology of a dedicated cancer hospital in North India.