On the estimation of the necessary inventory for hellenic public cord blood banks using simulation

Allogeneic hematopoietic stem cell transplantation is a relative new treatment method for a wide range of diseases including hematopoietic malignancies, immunodeficiency disorders, metabolic diseases and genetic disorders. Umbilical Cord Blood (UCB) is a modern and effective source of hematopoietic stem cells with increasing usage throughout the world. Thus, the establishment and operation of public UCB banks has emerged as a common practice all over the world. In Greece, the development of such a UCB bank network is still in its infancy. This paper presents the development of a methodology for estimating the required inventory level of UCB units in Greece (bank size), in order to ensure an adequate probability that a Greek patient finds a Human Leukocyte Antigen (HLA)‐compatible unit/donor (with a match at least for 4 out of 6 HLA histocompatibility antigens). To this end, we have adopted a Monte Carlo simulation approach. The available histocompatibility data include detailed genotypes of 8,500 Greeks. These data were fed into the system simulation model to emulate a UCB bank operation. The results of the simulation process reveal that an inventory of 10,000 cryopreserved UCB units could ensure a 4 out of 6 HLA matching for a Greek patient with a probability exceeding 95%. The determination of the bank size is a strategic, pivotal decision; thus, the proposed methodology provides the input for the National Healthcare System to decide on developing or not an UCB Bank (along with its designing parameters).