Bonaventure A, Harewood R, Stiller CA, Gatta G, Clavel J, Stefan DC, Carreira H, Spika D, Marcos-Gragera R, Peris-Bonet R, Pieros M, Sant M, Kuehni CE, Murphy MFG, Coleman MP, Allemani C; CONCORD Working Group.

Lancet Haematol. 2017 Apr 11.

Abstract

Bonaventure A, et al. – Survival inequalities globally for several subtypes of childhood leukaemia have been investigated by this work. This population–based study demonstrated that global inequalities in survival from childhood leukaemia have narrowed with time but remain very wide for both acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML). Useful information for health policy makers on the effectiveness of health–care systems and for cancer policy makers to reduce inequalities in childhood cancer survival are provided.

METHODS
This study asked to submit tumour registrations to cancer registries participating in CONCORD for all children aged 0–14 years who were diagnosed with leukaemia between Jan 1, 1995, and Dec 31, 2009, and followed up until Dec 31, 2009.
The clinicians categorized haematological malignancies by morphology codes in the International Classification of Diseases for Oncology, third revision.
Data from registries were excluded from which the data were judged to be less reliable, or included only lymphomas, and data from countries in which data for fewer than ten children were available for analysis.
Records were excluded because of a missing date of birth, diagnosis, or last known vital status.
5-year net survival (ie, the probability of surviving at least 5 years after diagnosis, after controlling for deaths from other causes [background mortality]) was measured for children by calendar period of diagnosis (1995–99, 2000–04, and 2005–09), sex, and age at diagnosis (<1, 1–4, 5–9, and 10–14 years, inclusive) using appropriate life tables.
Age-standardised net survival for international comparison of survival trends for precursor-cell acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML), was appraised.

RESULTS
Data from 89828 children from 198 registries in 53 countries, was examined.
5-year age-standardised net survival for all lymphoid leukaemias combined ranged from 10·6% (95% CI 3·1–18·2) in the Chinese registries to 86·8% (81·6–92·0) in Austria, during 1995–99.
It was observed that international differences in 5-year survival for childhood leukaemia were still large as recently as 2005–09, when age-standardised survival for lymphoid leukaemias ranged from 52·4% (95% CI 42·8–61·9) in Cali, Colombia, to 91·6% (89·5–93·6) in the German registries, and for AML ranged from 33·3% (18·9–47·7) in Bulgaria to 78·2% (72·0–84·3) in German registries.
With similar variation, survival from precursor-cell ALL was very close to that of all lymphoid leukaemias combined.
They observed that in most countries, survival from AML improved more than survival from ALL between 2000–04 and 2005–09.
Moreover, survival for each type of leukaemia varied markedly with age: survival was highest for children aged 1–4 and 5–9 years, and lowest for infants (younger than 1 year).
No systematic difference in survival between boys and girls, was noted.

The Lancet: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(17)33326-3/abstract