A prospective non-interventional study on the impact of transfusion burden and related iron toxicity on outcome in myelodysplastic syndromes undergoing allogeneic hematopoietic cell transplantation.

Most myelodysplastic syndromes (MDS)-patients receive multiple red blood cell transfusions (RBCT). Transfusions may cause iron-related toxicity and mortality, influencing outcome after allogeneic HSCT. This prospective non-interventional study evaluated 222 MDS and CMML patients undergoing HSCT. Overall survival (OS), relapse-free survival (RFS), non-relapse mortality (NRM), and relapse incidence (RI) at 36 months were 52%, 44%, 25%, and 31%, respectively. Age, percentage of marrow blasts and severe comorbidities impacted OS. RFS was significantly associated with RBCT burden prior to HSCT (HR: 1.7; p = .02). High ferritin levels had a significant negative impact on OS and RI, but no impact on NRM. Administration of iron chelation therapy prior to HSCT did not influence the outcome, but early iron reduction after HSCT (started before 6 months) improved RFS significantly after transplantation (56% in the control group vs. 90% in the treated group, respectively; p = .04). This study illustrates the impact of RBCT and related parameters on HSCT-outcome. Patients with an expected prolonged survival after transplantation may benefit from early iron reduction therapy after transplantation.

Factors affecting stem cell mobilization for autologous hematopoietic stem cell transplantation.

High-dose chemotherapy with autologous stem cell transplantation (ASCT) is curative treatment in various hematologic malignancies. Mobilization and collection of peripheral blood stem cell is the essential part of ASCT. The aim of this study was to evaluate the effectiveness of various mobilization regimens, determine the risk factors associated with mobilization failure (MF). We also investigated whether iron overload, which has an adverse impact on various aspects of HSCT including overall survival had any impact on mobilization kinetics. A total of 118 consecutive patients were included in this study. The rate of MF was 11.8 % with the first mobilization regimen. Frequency of MF was higher in lymphoma (P < 0.001) patients and in those receiving G-CSF alone (P= 0.01). Peripheral CD34+ cell count (P < 0.001), bone marrow cellularity (P < 0.001), reticulin fibrosis (P < 0.05) were significantly lower whereas serum ferritin levels (P = 0.06) tended to be higher in patients with MF. CD34+ cell count of the first apheresis product was positively correlated with the white blood cell count (P < 0.05; r = 0.232), platelet count (P = 0.01; r = 0.233), peripheral CD34+ cell count (P < 0.001; r = 0.704) and the grade of bone marrow reticulin fibrosis (P < 0.001; r = 0.366). Serum ferritin levels were negatively correlated with maximum peripheral CD34+ cell count (P = 0.02; r = -0.216) and the CD34+ cell count in the first product (P = 0.05; r = -0.183). Platelet count (P = 0.03; ß = 0.262), peripheral CD34+ cell count (P = 0.02; ß=0.279) were the two variables which remained to be significant in multivariate analysis. Predicting the poor mobilizers with the platelet count for instance may reduce the risk of MF by using more effective regimens in advance.