Development and operation of a program to obtain volunteer bone marrow donors unrelated to the patient.

Because of recent increases in bone marrow transplantation, the lack of available matched sibling donors has become a problem. This study investigated the feasibility of obtaining volunteer bone marrow donors unrelated to the patient. A program was developed to inform potential donors and obtain their consent for listing in a bone marrow donor registry. Sixty-six percent of whole blood or apheresis donors agreed to participate in the program. There were no demographic differences between those who accepted or declined to participate. Religion, experiences with medical practices, and the attitude of the potential donor's spouse were important factors in the decision to participate. A search for donors was initiated for 127 patients. Thirty searches were not completed, primarily because of patient-related problems. A total of 713 HLA-A and -B antigen-identical donors was located for 63 of the 97 (65%) patients. A total of 40 HLA-A, -B, and -DR antigen-identical donors was located for 18 of these 63 patients. Six of these 18 patients then had one or more donors (total, 9) whose lymphocytes did not react in mixed lymphocyte culture. Thus, using the file of 2147 donors, an HLA-identical donor was located for 6 percent of the 97 patients. None of these patients has yet received a transplant; in four cases this was due to patient-related and in two cases donor-related reasons. The cost to establish the donor program averaged $33.46 (1984) per donor for donors already typed for HLA-A and -B antigens. This experience indicated that, given thorough information about bone marrow donation and transplantation, a majority of blood and apheresis donors will volunteer to donate bone marrow, without feeling pressure to do so. A relatively small donor file provided donors for 6 percent of patients. The long-term value of bone marrow transplantation using unrelated donors and the optimum size of the donor file remain to be established.