Advantages of non-cryopreserved autologous hematopoietic stem cell transplantation against a cryopreserved strategy.

Autologous stem cell transplantation (auto-HSCT) is an effective treatment strategy for hematological malignancies. The standard mode of handling hematopoietic progenitors for the autologous procedure (CRYO) consists on its collection and freezing with dimethyl sulfoxide (DMSO) and its subsequent thawing and re-infusion. This process is toxic and expensive. Non-cryopreserved (non-CRYO) is a less expensive mode of auto-HSCT. We designed a comparative study between both strategies performed in two different centers to analyze the short-term complications. In total 111 auto-HSCT were performed from January/2015 to October/2016 (42 non-CRYO and 74 CRYO). There were 74 males and 69 (62%) patients had the underlying diagnosis of multiple myeloma. No differences were seen on the characteristics of the apheresis products and their viability. Engraftment was significantly faster in the non-CRYO group (p = 0.001). Febrile neutropenia and severe mucositis were lower in the non-CRYO group (40% vs 92% p = 0.0001 and 11% vs 64%, p = 0.001, respectively). In addition, length of hospitalization was 5 days shorter in the non-CRYO group (p = 0.0001). Overall responses and transplantation outcomes were similar. Our data demonstrate a clear advantage of the non-CRYO over CRYO auto-HSCT with faster engraftment, lower incidence of febrile neutropenia and shorter hospital stay after the transplantation procedure. These data are especially relevant for centers with high transplant activity or with limited resources.