Reduced 8-Gray Compared to Standard 12-Gray Total Body Irradiation for Allogeneic Transplantation in First Remission Acute Lymphoblastic Leukemia: A Study of the Acute Leukemia Working Party of the EBMT.

Abstract

In this registry-based study, we compared outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) in adult patients with acute lymphoblastic leukemia (ALL) transplanted in first complete remission (CR-1), following conditioning with total body irradiation (TBI) at a standard 12-Gray or at a lower 8-Gray total dose. Patients received fludarabine (flu) as the sole chemotherapy complementing TBI. Eight-Gray TBI/flu was used in 494 patients and 12-Gray TBI/flu in 145 patients. Eighty-eight (23.1%) and 36 (29%) of the patients had Ph-negative B-ALL, 222 (58.3%) and 53 (42.7%) had Ph-positive B-ALL, 71 (18.6%) and 35 (28.2%) T-ALL, respectively (P = 0.008). Patients treated with 8-Gray were older than ones received 12-Gray (median 55.7 versus 40.3 years, P < 0.0001) and were more frequently administered in vivo T-cell depletion (71% versus 40%, P <0.0001). In a multivariate model adjusted for age, type of ALL, and other prognostic factors, leukemia-free survival (primary endpoint) as well as relapse, nonrelapse mortality, overall survival, and GVHD-free, relapse-free survival were not influenced by the TBI dose. These results were confirmed when we focused on patients <55 years of age (median 47 years). Patients with Ph-positive ALL or T-ALL had significantly better survival outcomes than ones with Ph-negative B-ALL, mainly due to significantly fewer relapses. We conclude that 8-Gray TBI is sufficient for adult patients with ALL transplanted in CR-1 with no additional benefit of augmenting the conditioning intensity to 12-Gray.

• Authors: Alexandros Spyridonidis, Myriam Labopin, Bipin Savani, Sebastian Giebel, Gesine Bug, Stefan Schönland, Nicolaus Kröger, Matthias Stelljes, Thomas Schroeder, Andrew McDonald, Igor-Wolfgang Blau, Martin Bornhäuser, Montse Rovira, Wolfgang Bethge, Andreas Neubauer, Arnold Ganser, Jean Henri Bourhis, Matthias Edinger, Bruno Lioure, Gerald Wulf, Kerstin Schäfer-Eckart, Mutlu Arat, Zinaida Peric, Christoph Schmid, Ali Bazarbachi, Fabio Ciceri, Arnon Nagler, Mohamad Mohty
• Journal: HemaSphere (Hemasphere) Vol. 7 Issue 1 Pg. e812 (Jan 2023) ISSN: 2572-9241 [Electronic] United States
• PMID: 36698616 (Publication Type: Journal Article)
• Copyright: Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the European Hematology Association.