Disease Burden of Chronic Lymphocytic Leukemia within the European Union.

Introduction: While Chronic Lymphocytic Leukemia (CLL) is considered a rare disease, to our knowledge the current prevalence of the condition within the European Union (EU) member states is not published. Understanding the number of individuals with CLL is vital to assess disease burden within the wider population.

Methods: Using 2002 data from the International Agency for Research on Cancer (IARC), we estimated the number of individuals with CLL (ICD-10 C91.1) from those reported for all leukemias (C91–95) and extrapolated the figures by the population increase within the EU between 2002 and 2006, the last year with fully updated Community population estimates. One-year and 5-year partial prevalence estimates are reported (i.e. the number of individuals still living 1 and 5 years post diagnosis). We then applied proportional estimates from the literature to assess those requiring immediate treatment, those under observation and their likely progression rates.

Results: We found that within the 27 EU states plus Iceland, Norway and Lichtenstein, 1-year and 5-year CLL partial prevalence estimates totalled approximately 13,952 and 46,633 individuals respectively in 2006. If we apply Rai or Binet staging to the 1-year estimate, up to 45% of patients will be Stage III/IV or B/C and require immediate treatment. Thus 6,278 individuals may be treated within the first year of diagnosis. Of 55% (7673) under observation, by five years up to 33% (2,532) may have more advanced disease with increased risk of mortality.

Conclusion: While CLL is a rare disease, the number of individuals burdened by the disease within the EU is considerable and thousands of patients require treatment and physician care, which has cost implications for member states.