Clinical significance of total nucleated cell count in bone marrow of patients with acute lymphoblastic leukemia who underwent allogeneic hematopoietic stem cell transplantation.

The clinical implications of recipient bone marrow nucleated cell count (NCC) prior to allogeneic hematopoietic stem cell transplantation (allo-HSCT) remain unknown. We conducted a multicenter retrospective study to evaluate the clinical significance of bone marrow NCC prior to allo-HSCT in patients with acute lymphoblastic leukemia. Patients who were in remission and underwent the initial allo-HSCT were included and stratified into high- and low-NCC groups using an NCC of 10 × 10/µL as the cut-off. The 3-year overall survival (OS), non-relapse mortality (NRM), and relapse rates for the high- and low-NCC groups were 51.2 vs. 84.5% (p < 0.001), 27.5 vs. 6.5% (p < 0.001), and 31.1 vs. 24.4% (p = 0.322), respectively. The high-NCC group had significantly poorer OS and higher NRM when compared with the low-NCC group. In summary, high recipient bone marrow NCC is associated with higher NRM and lower OS following allo-HSCT.