Pediatric Acute Lymphoblastic Leukemia: From Diagnosis to Prognosis

Pediatric acute lymphoblastic leukemia is the most common childhood cancer. Although the appearance of the disease is often quite dramatic, there are many patients who present much more indolently, creating a diagnostic dilemma for the primary care pediatrician. The appropriate diagnostic work-up assesses the initial extent of disease and stability of a patient, and provides information that is important for risk stratification. Such information includes patient age and white blood cell count at diagnosis, leukemia immunophenotype, presence or absence of extramedullary disease, and blast cytogenetic abnormalities. After therapy is initiated, the response of the disease to treatment is key for predicting outcomes. Altogether, this information is used to guide overall treatment intensity. Chemotherapy is administered in sequential blocks or phases, and lasts for several years. In general, outcomes are excellent and the majority of patients survive, but there are still subsets of patients who do not fare as well, either due to resistant or recurrent disease, or due to long-term and late effects of therapy.