LP-04. Allogeneic hematopoietic stem cell transplantation for mature T/NK-cell lymphomas in children
Maria A. Klimentova, Margarita E. Perminova, Larisa N. Shelikhova, Sergey L. Blagov, Olga O. Molostova, Yulia G. Abugova, Natalia V. Myakova, Michael A. Maschan
Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
Contact: Dr. Maria A. Klimentova, phone: +7 (968) 808-16-48, e-mail: email@example.com
Mature T/NK cell lymphomas are often a highly aggressive disease, but their rare occurrence, especially in children, results in limited research data on treatment outcomes, including the results of allogeneic hematopoietic stem cell transplantation (HSCT). Our purpose was to evaluate the main outcomes of HSCT on the platform of selective depletion in children with mature T/NK-cell lymphomas.
Patients and methods
Nineteen pediatric patients with various types of mature T/NK-cell lymphomas (cutaneous T-cell lymphoma, ALK-positive anaplastic large cell lymphoma, hepatolienal γδT-cell lymphoma, nasal type T/NK-cell lymphoma) underwent allogeneic HSCT on the TCRαβ depletion platform from unrelated (n=6), or haploidentical donors (n=13). Nine patients (45%) had residual tumor at the time of HSCT, ten children were in complete remission. Myeloablative schedules based on total body irradiation (TBI) in 9 cases and treosulfan in 10 cases were used as a preparatory regimen.
Engraftment was recorded in 19 patients (100%). One patient died in the early period from infectious complications; the cumulative incidence of transplant-related mortality was 5%. The cumulative incidence of grade II-IV acute graft-versus-host disease (GvHD) was 32%, grade III-IV GvHD was 6%; chronic GvHD developed in 7% of cases. Disease progression or relapse was observed in 5 patients at a median of 101 days. The 5-year cumulative relapse incidence was 27% with event-free survival of 67%, and overall survival of 78%.
Allogeneic αβ T-cell-depleted HSCT may provide long-term overall survival in 78% of children with high-risk mature T-cell lymphomas, even if they received HSCT beyond the remission.
Mature T-cell lymphoma, children, allogeneic HSCT, αβ T-cell-depletion.