Persistently high incidence rates of childhood acute leukemias from 2010 to 2017 in Mexico City: A population study from the MIGICCL

Abstract

IntroductionOver the years, the Hispanic population living in the United States has consistently shown high incidence rates of childhood acute leukemias (AL). Similarly, high AL incidence was previously observed in Mexico City (MC). Here, we estimated the AL incidence rates among children under 15 years of age in MC during the period 2010–2017.MethodsThe Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia conducted a study gathering clinical and epidemiological information regarding children newly diagnosed with AL at public health institutions of MC. Crude age incidence rates (cAIR) were obtained. Age-standardized incidence rates worldwide (ASIRw) and by municipalities (ASIRm) were calculated by the direct and indirect methods, respectively. These were reported per million population <15 years of age; stratified by age group, sex, AL subtypes, immunophenotype and gene rearrangements.ResultsA total of 903 AL cases were registered. The ASIRw was 63.3 (cases per million) for AL, 53.1 for acute lymphoblastic leukemia (ALL), and 9.4 for acute myeloblastic leukemia. The highest cAIR for AL was observed in the age group between 1 and 4 years (male: 102.34 and female: 82.73). By immunophenotype, the ASIRw was 47.3 for B-cell and 3.7 for T-cell. The incidence did not show any significant trends during the study period. The ASIRm for ALL were 68.6, 66.6 and 62.8 at Iztacalco, Venustiano Carranza and Benito Juárez, respectively, whereas, other municipalities exhibited null values mainly for AML.ConclusionThe ASIRw for childhood AL in MC is among the highest reported worldwide. We observed spatial heterogeneity of rates by municipalities. The elevated AL incidence observed in Mexican children may be explained by a combination of genetic background and exposure to environmental risk factors.

Epidemiology of childhood acute leukemias in marginalized populations of the central-south region of Mexico: results from a population-based registry

“…However, these rates are intermediate in comparison to those reported for the European regions (42.1-57.1) ( 33 – 41 ) and Oceania (50.0-53.5) ( 42 – 44 ). They are lower than the rates reported for the North American regions (31.3-65.4) ( 1 , 9 , 45 – 53 ).…”

“…To date, few risk factors have been found to be associated with childhood leukemia and explain less than 10% of the causes of the disease ( 8 ). One of the regions of Mexico which has been explored further in previous studies is Greater Mexico City (GMC) where it has been reported that the incidence of AL is among the highest in the world ( 9 ). Moreover, the relapses and deaths in the early phases of treatment (first year after diagnosis) are at least three times more frequent than in high-income countries despite the use of the same chemotherapy regimens ( 10 , 11 ).…”

Implementation of a roadmap for the comprehensive diagnosis, follow-up, and research of childhood leukemias in vulnerable regions of Mexico: results from the PRONAII Strategy

“…In Mexico, the frequency of childhood leukemias, particularly, the incidence of ALL is among the highest reported in the world ( 8 ). Moreover, its mortality rate is 1.8 times higher than the global average ( 1 ).…”

“…This high percentage of genetic alterations in AML is of particular concern and significantly different from that in B-ALL ( 10 ). A recent study conducted in Mexico City reported that the incidence of AL is 63.3 (cases per million), 53.1 for ALL, and 9.4 for AML, placing them among the highest recorded globally ( 8 ). Mexico’s incidence rate of AL surpasses that of many other countries, and Hispanics living in the United States have a particularly challenging prognosis ( 11 – 13 ).…”

IKZF1plus is a frequent biomarker of adverse prognosis in Mexican pediatric patients with B-acute lymphoblastic leukemia

“…A better understanding of genomic alterations occurring in B-ALL pediatric leukemia and their clinical impact is crucial for Hispanic populations such as Mexicans. High incidence rates of childhood acute leukemia have been consistently observed in the Mexican population (55.0 cases per million children under 15 years of age) ( 25 – 27 ). Additionally, mortality and morbidity rates are higher than those in high-income countries, particularly as a consequence of deaths related to refractory disease and treatment-related toxicity ( 28 , 29 ).…”