(187) Prevalence of rare blood cancers in Europe: a population-based network cohort study part of DARWIN EU®

Publication Number: 1180

Background: There is a scarcity of data on the estimated prevalence of rare blood cancers. This is important as prevalence is one criterion that may influence the type of regulatory pathway available for treatments of rare conditions in Europe.

Objectives: To estimate the prevalence of follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL), multiple myeloma (MM), chronic lymphocytic leukaemia (CLL), acute myeloid leukaemia (AML), and acute lymphocytic leukaemia (ALL) from 2010 until most recently available data, in European databases onboarded in Phase I of DARWIN EU®.

Methods: Study design: Population-based cohort. EU PAS register number: EUPAS50800.
Setting: Data was included from primary care record databases mapped to the OMOP common data model: 1) Integrated Primary Care Information (IPCI), The Netherlands, 2) Sistema d’Informació per al Desenvolupament de la Investigació en Atenció Primària (SIDIAP), Spain, and 3) Clinical Practice Research Datalink (CPRD) GOLD database, 4) IQVIA DA Germany, and 5) IQVIA LPD Belgium. SIDIAP was further linked with hospital discharge data (CMBD).
Source population: One year of data visibility was required.
Outcomes: Primary outcome was 5-year partial prevalence where individuals were considered as a prevalent case for the five years following their initial diagnosis.
Statistical analysis: Point prevalence was estimated for the primary analysis, as of the 1st January for each year 2010-2020.

Results: A total of 35,109,377 individuals were included (CPRD GOLD: 9,192,128, IPCI: 2,157,533, IQVIA Belgium LPD: 677,667, IQVIA Germany DA: 15,542,676, and SIDIAP CMBD: 7,539,373) across all study years.
As of the 1st January 2020, 5-year partial prevalence estimates for ALL ranged between 0.44 (95% CI: 0.44 to 0.44) and 0.65 (0.65 to 0.65) per 10,000. Estimates for AML ranged between 0.72 (0.72 to 0.72) and 1.03 (1.03 to 1.03). Estimates for CLL ranged between 2.83 (2.83 to 2.83) and 4.13 (4.13 to 4.13). Estimates for DLBCL ranged between 0.47 (0.47 to 0.47) and 1.73 (1.73 to 1.73). Estimates for FL ranged between 0.90 (0.90 to 0.90) and 2.83 (2.83 to 2.83). Lastly, estimates for MM ranged between 2.15 (2.15 to 2.15) and 4.27 (4.27 to 4.27). All outcomes except ALL increased with age, with more obvious trends for CLL and MM. Prevalence generally increased during the study period, most markedly for MM.

Conclusions: ALL and AML were the least common blood cancers, followed by DLBCL and FL. Although MM and CLL were relatively more common, their estimated 5-year partial prevalence was below 5 per 10,000 using selected databases onboarded during Phase I of DARWIN EU®. Estimates for prevalence varied markedly by age and, for most outcomes, increased during the study period.