Baseline Characteristics Predicting Very Good Outcome of Allogeneic Hematopoietic Cell Transplantation in Young Patients With High Cytogenetic Risk Chronic Lymphocytic Leukemia - A Retrospective Analysis From the Chronic Malignancies Working Party of the EBMT
Abstract
Patients with chronic lymphocytic leukemia with del(17p) or del(11q) have poor long-term prognosis with targeted therapies. Conversely, this retrospective European Society for Blood and Marrow Transplantation registry study shows that young high cytogenetic risk responsive patients with human leukocyte antigen-matched donors have a high 8-year progression-free survival and low 2-year non-relapse mortality after allogeneic stem cell transplantation.
This treatment then may compare favorably with targeted therapies for younger high cytogenetic risk patients. Background: Patients with genetically high-risk relapsed/refractory chronic lymphocytic leukemia have shorter median progression-free survival (PFS) with kinase-and BCL2-inhibitors (KI, BCL2i).
Allogeneic hematopoietic stem cell transplantation (alloHCT) may result in sustained PFS, especially in younger patients because of its age-dependent non-relapse mortality (NRM) risk, but outcome data are lacking for this population. Patients and Methods: Risk factors for 2-year NRM and 8-year PFS were identified in patients < 50 years in an updated European Society for Blood and Marrow Transplantation registry cohort (n = 197; median follow-up, 90.4 months) by Cox regression modeling, and predicted probabilities of NRM and PFS of 2 reference patients with favorable or unfavorable characteristics were plotted.
Conclusion: Low predicted NRM and high 8-year PFS in favorable transplant high cytogenetic risk patients compares favorably with outcomes with KI or BCL2i. Taking into account the amount of uncertainty for predicting survival after alloHCT and after sequential administration of KI and BCL2i, alloHCT remains a valid option for younger patients with high cytogenetic risk chronic lymphocytic leukemia with a well-HLA-matched donor.