Characteristics and Outcome of Adolescents with Acute Lymphoblastic Leukemia (ALL) Differ from Young Children in the B-Cell Lineage but Not in the T-Cell Lineage: Experience of the ALL Israeli National Studies (INS)

The outcome of adolescents (≥ 15 years old) with ALL treated on contemporary pediatric ALL protocols has improved and compares favorably with the results of adolescents treated on adult protocols. However, the overall outcome of adolescents is still inferior to that of young children. In order to analyze this difference we compared early response to treatment and biological characteristics of various ALL subtypes (T-cell and non-T-cell), in these age groups. Between January 1989 and June 2008, a total of 942 patients, i.e.,83 (9%) aged ≥ 15 years, 162 (17%) aged 1050 chromosomes), higher incidence of Philadelphia chromosome, and normal karyotype compared to younger patients (1 Figure Figure