Hematopoietic stem cell transplantation in the Eastern Mediterranean Region (EMRO) 2011-2012: A comprehensive report on behalf of the Eastern Mediterranean Blood and Marrow Transplantation group (EMBMT)

Objective/background: The Eastern Mediterranean Blood and Marrow Transplantation (EMBMT) group has accumulated over 31 years of data and experience in hematopoietic stem cell transplantation (HSCT), particularly in hemoglobinopathies, severe aplastic anemia, inherited metabolic and immune disorders, in addition to a wide array of hematologic malignancies unique to this region. A regional update in current HSCT trends is highly warranted. We studied the trends of HSCT activities in World Health Organization-Eastern Mediterranean (EMRO) region, surveyed by the EMBMT, between 2011 and 2012.

Methods: Retrospective analysis of the survey data mainly of cumulative number of transplants, types of transplants (autologous vs. allogeneic), types of conditioning such as myeloablative versus reduced intensity was conducted. Also, trends in leukemias, hemoglobinopathies, severe aplastic anemia, inherited bone marrow failure syndromes, amongst others were analyzed.

Results: Twenty-one teams from nine EMRO countries reported their data (100% return rate) to the EMBMT for the years 2011-2012, with a total of 3,546 first HSCT (1,670 in 2011; 1,876 in 2012). Allogeneic HSCT (allo-HSCT) represented the majority (62%) in both years. The main indications for allo-HSCT were acute leukemias (988; 46%), bone marrow failure syndromes (421, 20%), hemoglobinopathies (242; 11%), and immune deficiencies (157; 7%). There was a progressive increase in the proportions of chronic myeloid leukemia cases transplanted beyond first chronic phase (37 [7%] of all chronic myeloid leukemia cases in 2011 vs. 39 [29%] in 2012). The main indications for autologous transplants were multiple myeloma/plasma cell disorders (510; 39%), Hodgkin lymphoma (311; 24%), non-Hodgkin lymphoma (259; 20%), and solid tumors (163; 12%). Reduced intensity conditioning continued to show a progressive decrease over years (9.5% in 2011 vs. 7.9% in 2012), yet remained relatively low compared with contemporary practices in Europe published by EBMT. The vast majority (91%) of allo-HSCT source was from sibling donors with continued dominance of peripheral blood (64%) followed by bone marrow (33%).While umbilical cord blood transplants increased to 4% of allo-HSCT, matched unrelated donor remained underutilized and there was no haplo-identical transplant reported. Large centers with >50 HSCT/year, showed a continued increase in the total number of allo-HSCT over the past 2years that may be related to capacity building issues and require further studies.

Conclusion: There is a discernable increase of HSCT rate in the EMRO region with a significant expansion in utilization of cord blood transplants and allogeneic peripheral blood-HSCT as a valuable source. However, further research of outcome data and the development of regional donor banks (cord blood and matched unrelated donors) may help to facilitate future planning to satisfy the escalating regional needs and augment collaboration within the EMBMT and globally.