Direct association of socio-economic status with T-cell acute lymphoblastic leukaemia in children

Abstract 

Lymphoblasts from 186 consecutive untreated children <18 years were analysed by flow cytometry in Brazil. Socio-economic status was defined by family income; undernourishment by height and weight for age standardised z scores below −1.28. The observed frequencies were precursor-B (pre-B) CD10 positive acute lymphoblastic leukaemia (ALL) (CD10⁺) 65%, pre-B CD10 negative (CD10⁻) 13%, and T-ALL 18%. The typical incidence peak at age 2–5 years was observed among the CD10 positive cases. Nutritional variables were not associated with immunophenotypes. Low monthly per capita income was associated with T-immunophenotype (P=0.024). In conclusion, a direct association between unfavourable socio-economic status and the T-phenotype indicates a potential role of socio-economic factors on the genesis of ALL in children, thus confirming indirect data of the international literature.

Abbreviations: ALL, acute lymphoblastic leukaemia, d.f., degrees of freedom, GCMTLA, Co-operative Group for Treatment of Acute Leukaemia in Minas Gerais, Brazil, WBC, peripheral white blood cell count, ZHEIGHT, height for age and sex standardised z score, ZWEIGHT, weight for age and sex standardised z score

Keywords: Acute lymphoblastic leukaemia, Immunophenotyping, Socio-economic status, Nutrition