A B S T R A C T PurposeThis report provides an overview of current childhood cancer statistics to facilitate analysis of the impact of past research discoveries on outcome and provide essential information for prioritizing future research directions. MethodsIncidence and survival data for childhood cancers came from the Surveillance, Epidemiology, and End Results 9 (SEER 9) registries, and mortality data were based on deaths in the United States that were reported by states to the Centers for Disease Control and Prevention by underlying cause. ResultsChildhood cancer incidence rates increased significantly from 1975 through 2006, with increasing rates for acute lymphoblastic leukemia being most notable. Childhood cancer mortality rates declined by more than 50% between 1975 and 2006. For leukemias and lymphomas, significantly decreasing mortality rates were observed throughout the 32-year period, though the rate of decline slowed somewhat after 1998. For remaining childhood cancers, significantly decreasing mortality rates were observed from 1975 to 1996, with stable rates from 1996 through 2006. Increased survival rates were observed for all categories of childhood cancers studied, with the extent and temporal pace of the increases varying by diagnosis. ConclusionWhen 1975 age-specific death rates for children are used as a baseline, approximately 38,000 childhood malignant cancer deaths were averted in the United States from 1975 through 2006 as a result of more effective treatments identified and applied during this period. Continued success in reducing childhood cancer mortality will require new treatment paradigms building on an increased understanding of the molecular processes that promote growth and survival of specific childhood cancers.

A B S T R A C T PurposeTo improve survival rates in children with acute myeloid leukemia (AML), we evaluated gemtuzumab-ozogamicin (GO), a humanized immunoconjugate targeted against CD33, as an alternative to further chemotherapy dose escalation. Our primary objective was to determine whether adding GO to standard chemotherapy improved event-free survival (EFS) and overall survival (OS) in children with newly diagnosed AML. Our secondary objectives examined outcomes by risk group and method of intensification. Patients and MethodsChildren, adolescents, and young adults ages 0 to 29 years with newly diagnosed AML were enrolled onto Children's Oncology Group trial AAML0531 and then were randomly assigned to either standard five-course chemotherapy alone or to the same chemotherapy with two doses of GO (3 mg/m 2 /dose) administered once in induction course 1 and once in intensification course 2 (two of three). ResultsThere were 1,022 evaluable patients enrolled. GO significantly improved EFS (3 years: 53.1% v 46.9%; hazard ratio [HzR], 0.83; 95% CI, 0.70 to 0.99; P ϭ .04) but not OS (3 years: 69.4% v 65.4%; HzR, 0.91; 95% CI, 0.74 to 1.13; P ϭ .39). Although remission was not improved (88% v 85%; P ϭ .15), posthoc analyses found relapse risk (RR) was significantly reduced among GO recipients overall (3 years: 32.8% v 41.3%; HzR, 0.73; 95% CI, 0.58 to 0.91; P ϭ .006). Despite an increased postremission toxic mortality (3 years: 6.6% v 4.1%; HzR, 1.69; 95% CI, 0.93 to 3.08; P ϭ .09), disease-free survival was better among GO recipients (3 years: 60.6% v 54.7%; HzR, 0.82; 95% CI, 0.67 to 1.02; P ϭ .07). ConclusionGO added to chemotherapy improved EFS through a reduction in RR for children and adolescents with AML. J Clin Oncol 32:3021-3032. © 2014 by American Society of Clinical Oncology INTRODUCTIONAcute myeloid leukemia (AML) is among the most difficult to treat of the childhood cancers because of its disease heterogeneity, high relapse, and toxic mortality.1,2 Therapeutic advances have included chemotherapy intensification and adding allogeneic stem-cell transplantation (SCT). Children's Oncology Group (COG) legacy AML trials evaluated time-intensive induction and observed improvement in event-free survival rates (EFS) from 27% to 42%. 3,4 Matched family-donor (MFD) transplantation improved disease-free survival rates (DFS) by between 8% and 10% and postremission overall survival (OS) by between 5% and 13% in two previous phase III trials. 4,5 However, treatmentrelated mortality (TRM) increased substantially with therapy intensification. Supportive care improvements reduced TRM (from 19% to 12%). 4 However, it is increasingly evident that the limits of treatment intensification have been reached, 4,6,7 necessitating alternative approaches. JOURNAL OF CLINICAL ONCOLOGY O R I G I N A L R E P O R TVOLUME 3021The cell-surface antigen, CD33, is present in more than 80% of patients with AML but is absent from pluripotent hematopoietic stem cells and is a well established immunoconjugate target. 8,9 Early studies ...

Translocations involving chromosome 11q23 frequently occur in pediatric acute myeloid leukemia (AML) and are associated with poor prognosis. In most cases, the MLL gene is involved, and more than 50 translocation partners have been described. Clinical outcome data of the 11q23-rearranged subgroups are scarce because most 11q23 series are too small for meaningful analysis of subgroups, although some studies suggest that patients with t(9;11)(p22;q23) have a more favorable prognosis. We retrospectively collected outcome data of 756 children with 11q23-or MLL-rearranged AML from 11 collaborative groups to identify differences in outcome based on translocation partners. All karyotypes were centrally reviewed before assigning patients to subgroups. The event-free survival of 11q23/ MLL-rearranged pediatric AML at 5 years from diagnosis was 44% (؎ 5%), with large differences across subgroups (11% ؎ 5% to 92% ؎ 5%). Multivariate analysis identified the following subgroups as independent prognostic predictors: t(1;11)(q21;q23) (hazard ratio [HR] ‫؍‬ 0.1, P ‫؍‬ .004); t(6; 11)(q27;q23) (HR ‫؍‬ 2.2, P < .001); t(10; 11)(p12;q23) (HR ‫؍‬ 1.5, P ‫؍‬ .005); and t(10;11)(p11.2;q23) (HR ‫؍‬ 2.5, P ‫؍‬ .005). We could not confirm the favorable prognosis of the t(9;11)(p22;q23) subgroup. We identified large differences in outcome within 11q23/MLL-rearranged pediatric AML and novel subgroups based on translocation partners that independently predict clinical outcome. Screening for these translocation partners is needed for accurate treatment stratification at diagnosis. (Blood. 2009;114:2489-2496)