Acute Lymphoblastic Leukemia with t(4;11)(q21;q23)/KMT2A-AFF1 Translocation: The Results of Allogeneic Hematopoietic Stem Cells Transplantation in Children and Adults

Aim. The aim was to evaluate the results of the allogeneic hematopoietic stem cells transplantation (allo-HSCT) in children and adults with the most prognostically unfavorable acute lymphoblastic leukemia (ALL) with t(4;11)(q21;q23)/KMT2A-AFF1 translocation. Methods. We examined 21 patients (12 females, 9 males) aged from 3 months to 48 years (median 18.9 years). The analysis of prognostic factors of overall (OS) and event-free survival (EFS) after allo-HSCT in patients of different age groups with various clinical, transplantation and cytogenetic characteristics was performed. Allo-HSCT from HLA-compatible related and unrelated donors, as well as haploidentical allo-HSCT were performed in 4, 9 and 8 patients of age groups 18 years, respectively. In 10 (48 %) patients, allo-HSCT was performed in the first remission, in 2 (10 %) patients in the second remission, and in 9 (43 %) patients during the disease relapse. Results. In 8 (38 %) patients, the only chromosomal disorder was the translocation t(4;11)(q21;q23). Additional changes in chromosomes were found in 11 (52 %) patients. In 8 (38 %) of them, 3 or more chromosomal abnormalities in the karyotype were found. According to the results of a univariant analysis, the OS and EFS were significantly different in patients with allo-HSCT performed in the first remission and at other stages of ALL (in the second remission and in relapse: p