Hematopoietic Stem Cell Transplant Activity in Latin America: Predominant Increase in Autologous and Modest Increase in Allogeneic HCT with High Use of Unrelated Cord Blood Grafts
Authors: Rolon Juliana Martinez , Baldomero Helen , Jaimovich Gregorio , Rivas Maria , Bouzas Luis Fernando , Bonfim Carmem Maria Sales , Palma Julia , Karduss-Urueta Amado , Ubidia Diana , Bujan-Boza Willem , Gonzalez-Ramella Oscar , Ruiz-Arguelles Guillermo J. , Gomez-Almaguer David , Espino German A. , Fanilla Ernesto , Gonzalez Derlis , Carrasco Antonio , Galeano Sebastian , Borelli Walter Gabriel , Gimenez Marcos Hernandez , Pasquini Marcelo C. , Kodera Yoshihisa , Niederwieser Dietger , Seber Adriana 
Published: November 2019

Abstract
More than a million HCT have been performed worldwide to date, but transplant rates and indications vary widely across regions. The Latin American Bone Marrow Transplantation Group (LABMT) was created under the auspices of the Worldwide Network for Blood and Marrow Transplantation (WBMT) in 2011 to assist in diffusing the practice, to integrate centers from multiple countries and to improve access to transplantation in the region. To evaluate the actual HCT activity, trends and contemporary practices in Latin America (LA), the LABMT surveyed centers for the annual activity from 2009 to 2012. Methods: The WBMT Global Activity Survey was used as a template and sent to all Hematology and HCT Societies in the region. This survey includes information of annual HCT numbers by center, indications, stem cell source and donor type. Results: A total of 11,116 HCT were performed between 2009 and 2012 with an increase in annual numbers from 2,517 in 2009 to 3,072 in 2012 (22%). The majority of the HCT were autologous (62%) with a 32% increase in activity over the period analyzed. In contrast, the increase in allogeneic HCT (6%) was relatively small. The majority of allogeneic HCT used related donors (n=3210), mostly HLA-identical peripheral blood (n=1812), bone marrow (n=1128) and non-identical related peripheral blood (n=156). Unrelated donor HCT (n=982) were performed mostly using cord blood (n=427), followed by bone marrow (n=332) and peripheral blood (n=223). In 2012, 91 teams from 12 countries reported 3,072 patients. Transplant rates (TR; HCT/10 million population) were 21 for allogeneic (ranging from 6 in Venezuela to 85 in Uruguay) and 60 for autologous HCT (ranging from 8 in Mexico to 215 in Uruguay). Unrelated donor TR was 5, ranging from 0 (Costa Rica, Panama, Peru, Paraguay and Venezuela) to 18 (Chile). Transplant center team density (team/10 million inhabitants) was 1.8 in 2012, with the highest in Uruguay (15), followed by Panama (8), Costa Rica (4), and Argentina (4). In comparison to other regions, transplant center density in LA was identical to the Asian Pacific region and lower than in Europe (7) or US/Canada (6). TR in LA compared to Asia/Pacific were higher for autologous (39 vs. 14) and lower for allogeneic (21 vs. 24, respectively, Table 1). Most transplant indications for autologous HCT (65% of all HCT) were plasma cell disorders (48%) and lymphomas (41%). Most allogeneic transplants (35% of all HCT) were performed for acute leukemias (58%, equally myeloid and lymphoid leukemias) and 18% for non-malignant disorders. Conclusion: While transplant indications are comparable to HCT performed in Europe and North America, transplant rates, transplant center and transplant team densities in LA are markedly lower. More autologous than allogeneic HCT are performed and autologous HCT increased considerably between 2009 and 2012. Unrelated donor TR is lower than in other regions. Initiatives are currently being taken to increase transplant activity, especially using alternative donor transplants within the region.
Table 1. Transplant Rates and Team Density Worldwide Transplant rates (HCT/10 million population) Team density Region POP TOTAL AUTO ALLO FAMILY SIBLING UNRELATED LA 511.7 60.0 39.2 20.9 16.0 14.3 4.9 1.8 SEAR/WPR 3078.0 38.6 14.2 24.4 12.5 8.2 11.9 1.8 EUROPE 846.4 379.3 222.5 156.8 68.2 57.0 88.6 7.6 USA/Canada 348.0 482.5 264.9 217.5 91.2 75.8 126.3 6.2 EMR/AFR 690.9 29.8 12.7 17.2 15.7 15.0 1.4 0.4 HCT, hematopoietic cell transplantation; POP, population; AUTO, autologous; ALLO, allogeneic; SEAR/WPR, South East Asia/Western Pacific Region; LA, Latin America; EMR/AFR; Eastern Mediterranean/African Region

Disclosures
No relevant conflicts of interest to declare.