OBJECTIVETo investigate the efficacy of hematopoietic stem cells cryopreserved by ladder-style freezing from low temperature refrigerator to liquid nitrogen in treatment of hematological malignancies, and to analyze the survival condition of patients after hematopoietic stem cell transplantation.

METHODSThe coyoprotectant formed by 3% hydroxyethyl starch, 4% albumin and 5% dimethyl sulfoxide (DMSO) was need for cryopreservation of hematopoietic stem cells,which were first placed in -80C low temperature refrigerator and then were stored in -196C liquid nitrogen tank. 98 cases of hemafologic malignancies (io cases of ALL, 24 cases of AML, L-cases of MM and 53 case of malignant lymphoma) were selected from January 2002 to December 2016, and recived transplantatin auto-hematopoiehc stem cells cryopresorved by above-mentined method. The overall survival rate (OS), progression-free survival (PFS) were analyzed statistically.

RESULTSOne case failed in implantation due to intracranial hemorrhage and the other 97 cases all succeeded in hematopoietic reconstitution. The average time needed for neutrophil count ≥0.5×10/L was 9.24±1.89 d, and the average time needed for blood platelet ≥20×10/L without platelet transfusion for 3 days was 11.04±1.84 d. The median survival time was 47.6 months (1-80 months). The 3 and 5 year OS rates were (97.2±1.9) %, (84.2±4.6) % and (77.8±5.6) %, respectively. 3- and 5-year PFS of patients were (74.4±5.1)% and (61.2±6.2)%.

CONCLUSIONladder-style freezing from low temperature refrigerator to liquid nitrogen can reach the same clinical transplantation effect with traditional programmed cooling freezing method in autologous hematopoietic stem cells transplantation. moreover the incidence of complications after transpeantatim does not show increase.