A survey of use of unrelated volunteer donor bone marrow transplantation at 46 centres worldwide, 1989-93. International Marrow Unrelated Search and Transplant (IMUST) Study.

Unrelated donor bone marrow transplantation is increasingly used to treat haemopoietic disorders where no HLA-identical sibling is available. The International Marrow Unrelated Search and Transplant Study has collected core data on consecutive unrelated donor BMT (UD-BMT) and HLA-identical sibling donor BMT (ID-BMT) performed in 46 participating centres world-wide between March 1989 and February 1993. Eighteen UD-BMT were performed in the first 6-month period in 14 participating centres, while in the last period there were 103 UD-BMT in 46 centres. The percentage of BMT recipients with the following diagnoses were: bone marrow failure UD-BMT 15% and ID-BMT 11%; AML 13% and 27%; ALL 18% and 17%; CML 48% and 31%; and other diseases 7% and 14%. Thirty-eight per cent of UD-BMT recipients had advanced disease compared with only 23% of ID-BMT recipients. Thirty six per cent of UD-BMT compared with 21% of ID-BMT recipients were under 16 years old. More extreme differences in pre-transplant clinical characteristics between UD and ID-BMT recipients were found when diagnosis and stage of disease were considered together. This survey indicates how UD and ID-BMT are currently used in the treatment of haematological disease; however, longer follow-up is required to assess the value of UD-BMT in the management of patients with bone marrow disorders.