First experience of allogeneic haematopoietic stem cell transplantation in patients with mantle cell lymphoma with a mutation in the TP53 gene

Introduction . Mutations in the TP53 gene in patients with mantle cell lymphoma (MCL TP53+) are associated with a low response to intensive chemotherapy (CT) and adverse outcomes. Allogeneic haematopoietic stem cells transplantation (allo-HSCT) is a curative approach in MCL-TP53+ patients. Aim . Efficacy and safety assessment of allo-HSCT in MCL-TP53+ patients. Main findings . During 2016–2020, allo-HSCT in MCL TP53+ was performed in three patients. Two of them were grafted from HLA-identical unrelated donors, and one — from a haploidentical donor. Pre-transplant conditioning was “fludarabine + treosulfan + melphalan” in one case, and “fludarabine + busulfan” — in the other two. In three patients, leukocyte and platelet counts were recovered at days +18 and +20, +17 and +21, +19 and +16 after allo-HSCT, respectively. Acute graft-versushost disease (aGVHD) was observed in all patients (grade I — in 2 patients, grade IV — in 1 patient). One patient developed chronic GVHD (cGVHD) of moderate grade. All three patients exhibited complete remission and 100% donor chimerism in allo-HSCT follow-up of 6, 15 and 40 months, respectively.