Splenic irradiation for myelofibrosis prior to hematopoietic cell transplantation: A global collaborative analysis

  • Nico Gagelmann
  • Gabriela S Hobbs
  • Edoardo Campodonico
  • Grzegorz Helbig
  • Polona Novak
  • Thomas Schroeder
  • Artur Schneider
  • Christina Rautenberg
  • Hans Christian Reinhardt
  • Linette Bosques
  • Michael Heuser
  • Victoria Panagiota
  • Felicitas Thol
  • Carmelo Gurnari
  • Jaroslaw P Maciejewski
  • Fabio Ciceri
  • Kristin Rathje
  • Marie Robin
  • Simona Pagliuca
  • Marie-Thérèse Rubio
  • Vanderson Rocha
  • Vaneuza Funke
  • Nelson Hamerschlak
  • Rachel Salit
  • Bart L Scott
  • Fernando Duarte
  • Iwona Mitrus
  • Tomasz Czerw
  • Raffaella Greco
  • Nicolaus Kröger

Abstract

Splenomegaly is the clinical hallmark of myelofibrosis. Splenomegaly at the time of allogeneic hematopoietic cell transplantation (HCT) is associated with graft failure and poor graft function. Strategies to reduce spleen size before HCT especially after failure to Janus kinase (JAK) inhibition represent unmet clinical needs in the field. Here, we leveraged a global collaboration to investigate the safety and efficacy of splenic irradiation as part of the HCT platform for patients with myelofibrosis. We included 59 patients, receiving irradiation within a median of 2 weeks (range, 0.9-12 weeks) before HCT. Overall, the median spleen size prior to irradiation was 23 cm (range, 14-35). Splenic irradiation resulted in a significant and rapid spleen size reduction in 97% of patients (57/59), with a median decrease of 5.0 cm (95% confidence interval, 4.1-6.3 cm). The most frequent adverse event was thrombocytopenia, with no correlation between irradiation dose and hematological toxicities. The 3-year overall survival was 62% (95% CI, 48%-76%) and 1-year non-relapse mortality was 26% (95% CI, 14%-38%). Independent predictors for survival were severe thrombocytopenia and anemia before irradiation, transplant-specific risk score, higher-intensity conditioning, and present portal vein thrombosis. When using a propensity score matching adjusted for common confounders, splenic irradiation was associated with significantly reduced relapse (p = .01), showing a 3-year incidence of 12% for splenic irradiation versus 29% for patients with immediate HCT and 38% for patients receiving splenectomy. In conclusion, splenic irradiation immediately before HCT is a reasonable approach in patients experiencing JAK inhibition failure and is associated with a low incidence of relapse.

Bibliographical data

Original languageEnglish
ISSN0361-8609
DOIs
Publication statusPublished - 05.2024

Comment Deanary

© 2024 The Authors. American Journal of Hematology published by Wiley Periodicals LLC.

PubMed 38357714