Quality assessment of cord blood units selected for unrelated transplantation: a transplant center perspective

Cord blood units (CBUs) are increasingly being used for unrelated allogeneic stem cell transplantation and their selection is mainly done according to pre-freezing cell dose and HLA donor/recipient compatibility. The main practical advantage of cord blood transplant (CBT) is represented by an easy and quick CBU procurement, due to the possibility of long-term storage of fully HLA typed CBUs assessed for cell dose and infectious contamination. The main disadvantage consists in a limited cell dose, with the consequent risk of graft failure or engraftment delay. In order to warrant the safety and the efficiency of CBUs selected for clinical use, transplant physicians may check CBU characteristics by requiring quality assessments (QAs) to the cord blood bank (CBB), to be performed on segments attached to and cryopreserved with the bags. However, there is a wide variability concerning CBU-QA with regard to the pre-transplant "release tests", mainly due to limited availability of segments attached to the CBU and of maternal samples and to difficult communication between Transplant Centres (TCs) and CBBs. The aim of this article is to describe a TC perspective during CBU selection for unrelated transplant, in order to identify an appropriate QA scheme and define the timing when the results need to be acquired. By analyzing the available data, this article describes a model of TC-QA policy able to guide the clinician from CBU selection through the infusion, with the ultimate aim of improving the transplant clinical outcome.