Inherited genetic polymorphisms
Genome-wide association studies show that some germline (inherited) genetic polymorphisms are associated with the development of childhood ALL. For example, the risk alleles of ARID5B are strongly associated with the development of hyperdiploid B-precursor ALL. ARID5B is a gene that encodes a transcriptional factor important in embryonic development, cell type–specific gene expression, and cell growth regulation.[26,27]
Some cases of ALL have a prenatal origin. Evidence in support of this comes from the observation that the immunoglobulin or T-cell receptor antigen rearrangements that are unique to each patient's leukemia cells can be detected in blood samples obtained at birth.[28,29] Similarly, in ALL characterized by specific chromosomal abnormalities, data exist to support that patients had blood cells carrying the abnormalities at the time of birth with additional cooperative genetic changes acquired postnatally.[28,29,30]
In one study, 1% of neonatal blood spots (Guthrie cards) tested positive for the TEL-AML1 translocation, far exceeding the number of cases of TEL-AML ALL in children. Other reports confirm  or do not confirm  this finding; nonetheless, this may support the hypothesis that additional genetic changes are needed for the development of this type of ALL. Genetic studies of identical twins with concordant leukemia further support the prenatal origin of some leukemias.
Overall Outcome for ALL
Among children with ALL, more than 95% attain remission, and approximately 80% of patients aged 1 to 18 years with newly diagnosed ALL treated on current regimens are expected to be long-term event-free survivors.[35,36,37,38,39,40]
Despite the treatment advances noted in childhood ALL, numerous important biologic and therapeutic questions remain to be answered before the goal of curing every child with ALL with the least associated toxicity can be achieved. The systematic investigation of these issues requires large clinical trials, and the opportunity to participate in these trials is offered to most patients/families.
Clinical trials for children and adolescents with ALL are generally designed to compare therapy that is currently accepted as standard with investigational regimens that seek to improve cure rates and/or decrease toxicity. In certain trials in which the cure rate for the patient group is very high, therapy reduction questions may be asked. Much of the progress made in identifying curative therapies for childhood ALL and other childhood cancers has been achieved through investigator-driven discovery and tested in carefully randomized, controlled clinical trials. Information about ongoing clinical trials is available from the NCI Web site.
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with childhood acute lymphoblastic leukemia. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.