Page 39 - Haematologica May 2022

HCT worldwide access
Methods
Study design
In this retrospective observational survey we analyzed the worldwide HCT activity from the first published series of bone marrow transplants collected from the scientific literature and from member societies for very early transplants.11 After 2006, activities were obtained annually through the WBMT network using a unified center-based reporting system. Information from 2016 onwards is given as prediction based on currently available incomplete and non-validated data.
Main outcome measures were the spread of HCT over time and transplant by donor type, country of origin, and WHO region. Secondary outcome measures were to document any trends in the number of HCT by donor type or region, to classify these trends, and quantify differences in the use of autologous or allogeneic HCT across indications and regions.
No individual patient data were used and no ethics committee approval was mandated. Outcome information is not available from our center-specific registry and we opted against the report of fragmented outcome information of just two developed regions (EBMT and CIBMTR).
Data collection and validation
Global transplant numbers by country of origin, year of trans- plant, disease and donor type (autologous vs. allogeneic) have been collected since 2006 (foundation year of the WBMT) in 194 WHO member states through the registries of the reporting mem- ber organizations, or national registries or transplant centers directly either in paper form or electronically using the standard- ized WBMT form. Detailed and validated information about main indication including stage of the disease, stem cell source, and allo- geneic (family matched, family mismatched and unrelated) donor type were obtained for the years 2006 to 2016. Data were validat- ed by a range of different independent systems; through confirma- tion by the reporting teams, following receipt of a computer print- out of the entered data, by selective comparison with MED- A/TED datasets in the EBMT or CIBMTR data system or by cross- checking for double reporting with national registries. Data were validated by onsite visits to selected teams to verify reported data as part of the quality control program within the European, North American, Latin American and Asia-Pacific organizations. On-site visits to selected teams were part of the quality-control accredita- tion program of JACIE (www.ebmt.org/jacie-accreditation) or FACT (www.factweb.org). Based on quality controls and contacts with reg- ulatory agencies or national offices, the response rate for allogene- ic HCT was estimated to be >95% and for autologous HCT 80– 90%. The number of potential missing transplant numbers is esti- mated to be less than 5% for allogeneic HCT and less than 15% for autologous HCT. This number is much lower for Australia, Canada, Europe, Japan, and the USA. The survey focuses on the numbers of patients treated for the first time with HCT.
Participating hematopoietic cell transplantation (HCT) teams, groups, countries and continents
In 2016, 1,662 HCT teams in 86 countries over six WHO conti- nental regions delivered HCT services globally [(www.who.int/about/regions/en/). These regions included the Americas (AMR/PAHO; WHO regions North-, Middle and South America and Canada); Asia (SEAR/WPR; WHO regions South East Asia and Western Pacific Region, which includes Australia and New Zealand); Europe (EUR; which includes Turkey and Israel) and AFR/EMR (WHO regions Africa and Eastern Mediterranean). For specific analyses AMR/PAHO activities were divided in North America and Latin-America and AFR/EMR in Africa and EMR. A
detailed list of organizations providing activity data and defini- tions used in the manuscript are reported in the Online Supplementary Appendix.
Statistical analysis
The data analysis was comprised of ordinary least squares regressions for trends, c2 tests for independent proportions of indi- cations, and binomial tests for donor type. Calculations were done in Eviews8 and Excel 2010 (Microsoft).
Results
Total hematopoietic cell transplantations and overall trends
From 1957-2016, a total of 1,298,897 HCT (57.1% autol- ogous) procedures were recorded. The cumulative num- bers increased continuously from 10,000 in 1985, to 500,000 in 2005 and doubled to 1 million HCT by 2012. Projecting a frequency of at least 86,844 HCT for 2017 and 89,510 HCT for 2018 (incomplete and not validated data), a total of 1.5 million HCT worldwide was expected to be reached by 2019 (Online Supplementary Figure S1). The annual activity increased continuously from 46,563 in 2006 to 82,718 in 2016, amounting to a global increase of 77.6% since 2006, which was somewhat higher in allo- geneic (89.0%) than in autologous HCT (68.9%, Table 1). The yearly increase was by a median of 5.9% for all HCT (allogeneic 6.8% and autologous 5.9%) to a total of 697,934 procedures (54% autologous) since 2006. The most frequent indications were lymphoproliferative disor- ders (LPD; n=370,884 HCT of which 88.4% were autolo- gous) and leukemia (n=248,860 total of which 94.9% were allogeneic; see the Online Supplementary Figure S2). Global HCT team numbers plateaued in the last 4 years with a slight increase in 2016 (Online Supplementary Figure S3), while annual HCT numbers increased continuously. The increase was not a consequence of more reporting HCT teams, but of increased activity per HCT team. While the overall number of HCT per team was 35.1 in 2006, this reached 49.8 in 2016 (Online Supplementary Figure S3). Absolute numbers of all HCT per countries ranged from 0 to 19,505.
Hematopoietic cell transplantation teams activity in 2016
In 2016, the rates of HCT exceeded 80,000 HCT per year for the first time with 82,718 HCT (53.5% autolo- gous) reported in the global HCT activity survey (Table 1). The majority of HCT were performed in Europe (45.2%) and in North America (24.4%), while SEAR/WPR con- tributed with 22.7%, Latin-America with 5.1% and AFR/EMR with 2.7%. The trends for TR were somewhat different, with rates highest in North America (561 TR), followed by Europe (439 TR), Latin America (77 TR), SEAR/WPR (54 TR), EMR (36 TR) and Africa (9 TR) (Figure 1). TR were higher for autologous than for allo- geneic HCT in all regions except for SEAR/WPR, EMR and AFR. TR for allogeneic HCT ranged from 0.3 in Morocco to 414.0 in Israel (median 47.6); and for autologous HCT from 0.1 in Egypt to 705.9 in Iceland (median 99.1).
The number of HCT teams varied considerably across regions, with the highest numbers being in SEAR/WPR and Europe (Figure 2). In contrast, TD ranged from 0.05- 29.4/country and was highest in Europe (7.7 TD) followed
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