The Comparison of Results of Autologous Transplantation Using Non-Cryopreserved and Cryopreserved Hematopoietic Stem Cells (HSC)

Background: Bone marrow (peripheral blood stem cells (PBSCs)) autologous transplantation is the standard care for transplant-eligible patients with multiple myeloma. This treatment option is somewhat limited due to the high consumption of economic resources and the access to Cryobank. We performed a retrospective analysis of multiple myeloma patients who underwent autologous transplantation using non-cryopreserved and сryopreserved grafts at our institution from March 2016 to April 2020. Aim: Compare the results of autologous transplantation using non-cryopreserved and cryopreserved hematopoietic stem cells (HSC). Methods: 78 patients with MM were included in the study (male/female ratio 1.3:1). All patients got the standard immunochemotherapy programs. They had remission (≥partial response) till the auto-HSCT. Patients were divided in two groups depending on the technique of HSC storage: non-CRYO (n=35) and CRYO (n=43). Cryopreservation is a standard method of storage of HSC suspension. In our work we used the native HSC suspension which was saved from +4 °C to +6 °C during 72 - 120 hours. An effectivity and safety were evaluated in such parameters as the number of CD34+ and 7AAD- cells, colony-forming ability (CFA). All of these were made after apheresis and before reinfusion of HSC. Also, we compared the duration of hematopoiesis's recovery, the number of platelet transfusions, the length of hospitalization after auto-HSCT. Additionally, the effectiveness of therapy was assessed according to the IMWG response criteria and the level of residual tumor load before SCT and on day +100. Results: There were no differences in the total number of CD34 + cells x 106/kg, or in the level of 7AAD- cells, or in the total CFA. However, there was a significant difference in the percentage of loss of CD34+ cells from the moment of apheresis to the moment of reinfusion. We suppose it was caused adverse effects by temperature changes in CRYO group. In both groups, there were no severe infusion reactions on day 0. The adverse events (nausea, vomiting, tachycardia, increased total bilirubin and indicator liver enzymes) were absent in the non-CRYO group. But 29/43 (67.4%) patients had such symptoms in the CRYO group on day 0. The results are presented in the comparison table (image 1) of the evaluated parameters. All patients had full recovery of hematopoiesis till discharge from the hospital. Neutrophil recovery was achieved at 11th day (range 9-14) and platelets at 12th d