[Diagnosis and treatment of pediatric acute lymphoblastic leukemia: Historical review]

Acute lymphoblastic leukemia (ALL) is the most common malignant neoplasm in childhood, with the highest incidence occurring between 10 and 14 years of age in the Mexican population. ALL results from the abnormal proliferation of a malignant clone of leukocytes. The Mexican pediatric population exhibits idiosyncratic characteristics that are associated with a less favorable prognosis compared to the Caucasian population. In 1847, Rudolph Virchow first coined the term leukemia. In 1976, the French-American-British classification was introduced, which described the morphological characteristics of leukemic cells as L1, L2, and L3, providing greater diagnostic accuracy and distinguishing between myeloid and lymphoid leukemia. At that time, the disease-free survival rate was 20%. In 2008, the World Health Organization (WHO) introduced an immunological classification based on the immunophenotype of leukemias, marking a new era in the prognosis and clinical management of the disease. This classification reduced interobserver morphological diagnostic errors by identifying antigens that classify the cell lineage and maturation stage. The expression and combination of cellular antigens, as well as molecular rearrangements, are directly associated with the prognosis of ALL. Treatment has evolved alongside diagnostic advances in recent years, with strategies aimed at limiting treatment-related toxicity through safer chemotherapy regimens.