Noncryopreserved and cryopreserved peripheral blood stem cells (PBSC) lead to similar patient outcomes after transplant, according to a recent study.
Andrei Garifullin, MD, of the Russian Scientific Research Institute of Hematology and Transfusiology of Federal Medical Biological Agency and St Petersburg University in Russia, and colleagues conducted the research and presented their findings at the Tenth Annual Meeting of the Society of Hematologic Oncology.
Dr. Garifullin and colleagues conducted the research because autologous PBSC transplantation is the standard of care for transplant-eligible patients with multiple myeloma and cryopreservation is the standard cell storage method, but the “treatment option is somewhat limited due to the high consumption of economic resources and the access to cryobank,” they wrote.
The single-center retrospective study compared the results of patients with multiple myeloma who received autologous transplantation with cryopreserved cells (n=43) or noncryopreserved cells (n=35). All patients received standard immunochemotherapy programs and went into remission.
The 2-year progression-free survival rate was 96% in the group of patients receiving noncryopreserved cells and 82% in patients receiving cryopreserved cells.
“The identified trend requires further observation in subsequent survival assessments,” the researchers wrote.
Of the patients who received noncryopreserved cells, 37% had a partial response rate before transplant, 40% had a very good partial response, and 23% had a complete response. Of the patients who received cryopreserved cells, 72% had a partial response before transplant, 14% had a very good partial response, and 14% had a complete response. The minimal residual disease negativity rate was 37.5% before transplant in patients who received noncryopreserved cells and 16% in patients who received cryopreserved cells.
The posttransplant complete response rate was slightly higher in patients who received noncryopreserved cells (37%) than in patients who received cryopreserved cells (32%). A posttransplant very good partial response occurred in more patients who received noncryopreserved cells (40%) than patients who received cryopreserved cells (21%). The posttransplant partial response rate was 23% in patients who received noncryopreserved cells and 47% in patients who received cryopreserved cells.
The minimal residual disease negativity rate was higher after transplant in patients who received noncryopreserved cells (54.5%) than in patients who received cryopreserved cells (33%).
The researchers assessed the number of CD34-positive and 7AAD-negative cells and colony-forming ability after apheresis and before transplantation. There were no significant differences in the total number of CD34-positive cells, 7AAD-negative cells, or colonies between groups.
However, cryopreserved cells had a significantly higher percentage of lost CD34-positive cells (66.6%) from the moment of apheresis to the moment of reinfusion than the noncryopreserved cells (34.8%; P=.002). The absolute CD34-positive cell count was also significantly higher in cryopreserved cells at the time of reinfusion (1.44) than in noncryopreserved cells (0.65; P=.00005).
“We suppose it was caused by adverse effects of temperature changes in the cryro[preserved] group,” Dr. Garifullin and colleagues wrote.
Patients who received noncryopreserved cells achieved neutrophil recovery at the 11th day (range, 9th-14th day), while patients who received cryopreserved cells achieved neutrophil recovery at the 10th day (range, 8th-14th day). Platelet recovery occurred at the 12th day (range, 8th-19th day) in patients who received noncryopreserved cells and in those who received cryopreserved cells (range, 8th-20th day).
“The method of storage of PBSCs without cryopreservation is equal to traditional method controlled freezing and can be used in hospitals which have no cryobank,” the researchers concluded.
Garifullin A, Voloshin S, Linnikov S, et al. The use of non-cryopreserved and cryopreserved hematopoietic stem cells for autotransplantation in multiple myeloma. Poster MM-414. Presented at the Tenth Annual Meeting of the Society of Hematologic Oncology; September 28-October 1, 2022; Houston, TX.