title: The increase of the global donor inventory is of limited benefit to patients of non-Northwestern European descent.
abstract: Between 2001 and 2012, the number of unrelated donors registered worldwide increased from 7 to 21 million, and the number of public cord blood units increased to over 500,000. We addressed the question of whether this expansion resulted in higher percentages of patients reaching transplantation. Unrelated donor searches were evaluated for 3,124 eligible patients in the Netherlands in two cohorts (2001-2006, n=995; 2007-2012, n=2129), comparing results for patients of Northwestern European and non-Northwestern European origin. Endpoints were 'donor found' and 'transplantation reached'. The substantial growth of the donor inventory over the period studied did not increase the median number of potential unrelated donors (n=7) for non-Northwestern European patients, but almost doubled the number for Northwestern European patients from 42 to 71. Before and after 2007, an unrelated donor or cord blood was identified for 91% and 95%, respectively, of Northwestern European patients and for 65% and 82% of non-Northwestern European patients (P<0.0001). Non-Northwestern European patients more often needed a cord blood transplant. The degree of HLA matching was significantly lower for non-Northwestern European patients (P<0.0006). The time needed to identify a donor decreased for both populations. The percentage of Northwestern European patients reaching transplantation increased from 77% to 83% and for non-Northwestern European patients from 57% to 72% (P=0.0003). The increase of the global inventory resulted in more transplants for patients lacking a family donor, although the quality and quantity of (potential) haematopoietic cell grafts for patients of a non-Northwestern European descent remained inferior, indicating the need for adaptation of recruitment.
authors: Europdonor Foundation, Leiden, the Netherlands a.vanwalraven@sanquin.nl.|Sanquin, Amsterdam, the Netherlands.
authors: Suzanna M
authors: SM
authors: van Walraven
authors: Sanquin, Amsterdam, the Netherlands.|Leiden University Medical Center, Immunohematology and Blood Transfusion, Leiden.
authors: Anneke
authors: A
authors: Brand
authors: Europdonor Foundation, Leiden, the Netherlands.
authors: Jack N A
authors: JN
authors: Bakker
authors: Dutch Transplant Foundation, Leiden, the Netherlands.
authors: Martin B A
authors: MB
authors: Heemskerk
authors: Stem Cell Donor Bank Europdonor Nijmegen, University Medical Center Nijmegen St. Radboud, the Netherlands.
authors: Suzan
authors: S
authors: Nillesen
authors: University Medical Center Utrecht / Wilhelmina Kinderziekenhuis, Pediatric Stem Cell Transplantation Team, Leiden, the Netherlands.
authors: Marc B
authors: MB
authors: Bierings
authors: University Medical Center Groningen, Laboratory for Transplant Immunology, Leiden, the Netherlands.
authors: Laura B
authors: LB
authors: Bungener
authors: University Medical Center Groningen, Laboratory for Transplant Immunology, Leiden, the Netherlands.
authors: Bouke G
authors: BG
authors: Hepkema
authors: Leiden University Medical Center, Willem Alexander Kinderziekenhuis, Department for Pediatric Stem Cell Transplantation, Leiden, the Netherlands.
authors: Arjan
authors: A
authors: Lankester
authors: Stem Cell Donor Bank Europdonor Nijmegen, University Medical Center Nijmegen St. Radboud, the Netherlands.|Radboud University Medical Center, Laboratory Medical Immunology, Nijmegen, the Netherlands.
authors: Arnold
authors: A
authors: van der Meer
authors: Sanquin, Department of Transfusion Medicine, Rotterdam, the Netherlands.
authors: Kees
authors: K
authors: Sintnicolaas
authors: Sanquin, Department of Transfusion Medicine, Rotterdam, the Netherlands.
authors: Judith A E
authors: JA
authors: Somers
authors: University Medical Center Utrecht, Department of Immunology, HLA laboratory, Maastricht, the Netherlands.
authors: Eric
authors: E
authors: Spierings
authors: University Hospital Maastricht, Transplantation Immunology, Tissue Typing Laboratory, Maastricht, the Netherlands.
authors: Marcel G J
authors: MG
authors: Tilanus
authors: University Hospital Maastricht, Transplantation Immunology, Tissue Typing Laboratory, Maastricht, the Netherlands.
authors: Christien E M
authors: CE
authors: Voorter
authors: Erasmus University Medical Center, Department of Hematology, Rotterdam, the Netherlands.
authors: Jan J
authors: JJ
authors: Cornelissen
authors: Europdonor Foundation, Leiden, the Netherlands.|Leiden University Medical Center, Immunohematology and Blood Transfusion, Leiden.
authors: Machteld
authors: M
authors: Oudshoorn
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000706:statistics & numerical data; D006650:Histocompatibility Testing; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy; D009426:Netherlands; D044382:Population Groups; D012042:Registries; D014019:Tissue Donors; D055815:Young Adult