All issues > Volume 50(7); 2007

Review Article

Korean J Pediatr. 2007;50(7):601-605. Published online July 15, 2007.

Acute lymphoblastic leukemia in children: past, present and future

Hyoung Jin HJ Kang¹, Hee Young HY Shin¹, Hyo Seop HS Ahn¹

¹Department of Pediatrics, Cancer Research Institute Seoul National University College of Medicine, Seoul, Republic of Korea

Correspondence Hyo Seop HS Ahn ,Email: hsahn@snu.ac.kr

Abstract

The cure rate of acute lymphoblastic leukemia (ALL) in children dramatically improved over past 5 decades from zero to about 80%. The main cause of improvement is owing to the development of chemotherapy by multicenter clinical trial of large study groups with the understanding of leukemia biology. Recently, pediatric ALL protocols were applied to the treatment of adolescent and even adult ALL patients. For nearly 30 years, clinical factors have been used to risk-stratify therapy for children with ALL, so that the most intensive therapies are reserved for those patients at the highest risk of relapse. The risk groups of ALL are divided as standard- (low- plus intermediate-), high- and very high-risk group according to the prognostic factors, and treatment results improved by this risk based treatment. The factors used to risk-stratify therapy include age, gender, presenting leukocyte count, immunophenotype, cytogenetic aberrations including ploidy and translocations, and initial response after 1 to 2 weeks of therapy. But treatment efficacy is the most important determinant and can abolish the clinical significance of most, if at all, prognostic factors. Today, in the era of intensive, multiagent regimens, there is increasing evidence that we have reached the limits of prognostic significance of currently applied clinical risk factors in childhood ALL. As the cure rate of ALL is about 80%, introducing new prognostic factors such as new molecular prognostic markers, new methods of assessment about minimal residual disease, and pharmacogenetic study, with the development of stem cell transplantation and molecular targeted therapy are needed to cure residual 20% of childhood ALL patients without short and long term complications.

Keywords :Acute lymphoblastic leukemia, Children, Adolescent, Multicenter clinical trial