Sociodemographic and Birth Characteristics in Infant Acute Leukemia: A Review

Abstract

Acute leukemias are cancers of the hematopoietic system that involve, in the majority of cases, a malignant transformation of myeloid and lymphoid progenitor cells [1]. Acute leukemias represent the most common type of childhood cancer [2,3]. Acute lymphoblastic leukemia (ALL) has a frequency of five times greater than that of acute myeloblastic leukemia (AML) and is the most common cancer in children, representing 25% to 35% of all childhood cancers [3,4]. The incidence of ALL varies significantly among developed and developing countries. With a reported annual incidence of 20-45 cases per million children, the highest incidence rates are recorded in the Hispanic population in California, Texas and Florida and in Costa Rica and the City of Mexico [4-7]. Despite advances in therapy and improvements in survival, acute leukemia represents one of the main causes of morbidity and mortality in children. The etiology of this disease remains unknown. Only Down syndrome and ionizing radiation have been recognized as risk factors for the development of childhood acute leukemia [8]. However, the risk attributable to these factors is very small. Epidemiological studies exploring different environmental exposures along with advances in cytogenetics and immunophenotyping have identified different subgroups of the disease that must be considered separately. Such is the case of infantile leukemia. Although it is a rare disease in this group, the molecular character‐ istics and survival are different in infants than in older children, suggesting that the etiology is distinct and most likely involves prenatal factors. The purpose of this chapter is to introduce the reader to a systematic review of the current literature on reported risk factors for childhood acute leukemia (AL). This review reports what is currently known about acute leukemia in infants and future directions.