Despite Improvements, Survival Disparities Persist for Childhood Leukemia
Leukemia remains the most common cancer type for children aged 14 years or younger, worldwide, representing a third of cases for children younger than 10 years.
Researchers confirmed marked disparities in childhood leukemia survival around the world, with 5-year survival rates for acute lymphoblastic leukemia (ALL) ranging from 52% in Columbia to 92% in Germany, according to an article published in The Lancet Haematology.1
The study included data for nearly 90,000 children from 53 countries who were diagnosed with cancer between 1995 and 2009.
Leukemia remained the most common cancer type for children aged 14 years or younger, worldwide, representing a third of cases for children younger than 10 years. Lymphoid leukemias together represented 81% of all childhood leukemias worldwide, the team reported; acute myeloid leukemia (AML) represented 16% of cases; unspecified and other specified types of leukemia made up 3% of cases overall.
“There was no systematic difference in survival between boys and girls,” the researchers noted. Internationally, survival for both ALL and AML was worst among infants (patients diagnosed before age 1 year).
Survival rates for AML improved more steeply than for ALL survival rates between 2000 to 2004 and 2005 to 2009, but remained lower than ALL survival rates. The age-standardized 5-year survival rate for AML between 1995 and 1999 ranged from 4.2% in China to 59% in the United Kingdom and 78% in Germany. AML survival improved “quite remarkably” in most countries, including a jump from 4.2% to 41.1% in Chinese registries.
In the United States, pediatric lymphoid leukemia 5-year survival rates varied between 77% (for mature B cell ALL during 1995 to 1999) and 88.7% (for the same diagnosis during 2005 to 2009). US AML survival rates were 51.5% and 63.3% during 1995 to 1999 and 2005 to 2009, respectively.
Diagnostic precision varied by country; unspecified or other leukemia types represented only 2% and 3% of cases in North America and Europe, respectively, but 8% in Asia and 6% in Africa. In China, Latvia, and Jakarta, Indonesia, more than a quarter of diagnoses were coded as “unspecified or other” leukemias, the authors noted.
- Bonaventure A, Harewood R, Stiller CA, et al. Worldwide comparison of survival from childhood leukaemia for 1995-2009, by subtype, age, and sex (CONCORD-2): a population-based study of individual data for 89 828 children from 198 registries in 53 countries. Lancet Haematol. 2017 Apr 11. doi: 10.1016/S2352-3026(17)30052-2 [Epub ahead of print]