To examine population-based improvements in survival and the impact of clinical covariates on outcome among children and adolescents with acute lymphoblastic leukemia (ALL) enrolled onto Children's ...Oncology Group (COG) clinical trials between 1990 and 2005.
In total, 21,626 persons age 0 to 22 years were enrolled onto COG ALL clinical trials from 1990 to 2005, representing 55.8% of ALL cases estimated to occur among US persons younger than age 20 years during this period. This period was divided into three eras (1990-1994, 1995-1999, and 2000-2005) that included similar patient numbers to examine changes in 5- and 10-year survival over time and the relationship of those changes in survival to clinical covariates, with additional analyses of cause of death.
Five-year survival rates increased from 83.7% in 1990-1994 to 90.4% in 2000-2005 (P < .001). Survival improved significantly in all subgroups (except for infants age ≤ 1 year), including males and females; those age 1 to 9 years, 10+ years, or 15+ years; in whites, blacks, and other races; in Hispanics, non-Hispanics, and patients of unknown ethnicity; in those with B-cell or T-cell immunophenotype; and in those with National Cancer Institute (NCI) standard- or high-risk clinical features. Survival rates for infants changed little, but death following relapse/disease progression decreased and death related to toxicity increased.
This study documents ongoing survival improvements for children and adolescents with ALL. Thirty-six percent of deaths occurred among children with NCI standard-risk features emphasizing that efforts to further improve survival must be directed at both high-risk subsets and at those children predicted to have an excellent chance for cure.
BACKGROUND
To evaluate whether progress continues in identifying more effective treatments for children and adolescents with cancer, the authors examined both overall and disease‐specific childhood ...cancer mortality rates for the United States, focusing on data from 2000 to 2010.
METHODS
Age‐adjusted US mortality trends from 1975 to 2010 were estimated using joinpoint regression analysis. Analyses of annual percentage change (APC) were performed on the same diagnostic groupings for the period restricted to 2000 through 2010 for groupings ages <20 years, <15 years, and 15 to 19 years.
RESULTS
After a plateau in mortality rates during 1998 to 2002 (APC, 0.3%), the annual decline in childhood cancer mortality from 2002 to 2010 (APC, −2.4%) was similar to that observed from 1975 to 1998 (APC, −2.7%). Statistically significant declines in mortality rates from 2000 to 2010 were noted for acute lymphoblastic leukemia, acute myeloid leukemia, non‐Hodgkin lymphoma, Hodgkin lymphoma, neuroblastoma, central nervous system cancers, and gonadal cancers. From 2000 to 2010, the rates of decline in mortality for the group ages 15 to 19 years generally were equal to or greater than the rates of decline for the group ages birth to 14 years. Improvements in treatment since 1975 resulted >45,000 cancer deaths averted through 2010.
CONCLUSIONS
Cancer mortality for both children and adolescents declined from 2000 to 2010, with significant declines observed for multiple cancer types. However, greater than 1900 cancer deaths still occur each year among children and adolescents in the United States, and many survivors experience long‐term effects that limit their quality of life. Continued research directed toward identifying more effective treatments that produce fewer long‐term sequelae is critical to address these remaining challenges. Cancer 2014;120:2497–2506. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Cancer mortality for both children and adolescents declined between 2000 and 2010, with significant declines observed for multiple cancer types. However, more than 1900 cancer deaths still occur each year among children and adolescents in the United States, and many survivors experience long‐term effects that limit their quality of life, emphasizing the need for continued research to address these remaining challenges.
Summary Cancer in children and adolescents is rare and biologically very different from cancer in adults. It accounts for 1·4% of all cancers worldwide, although this proportion ranges from 0·5% in ...Europe to 4·8% in Africa, largely because of differences in age composition and life expectancy. In high-income countries, survival from childhood cancer has reached 80% through a continuous focus on the integration of clinical research into front-line care for nearly all children affected by malignant disease. However, further improvement must entail new biology-driven approaches, since optimisation of conventional treatments has in many cases reached its limits. In many instances, such approaches can only be achieved through international collaborative research, since rare cancers are being subdivided into increasingly smaller subgroups on the basis of their molecular characteristics. The long-term effect of anticancer treatment on quality of life must also be taken into account because more than one in 1000 adults in high-income countries are thought to be survivors of cancer in childhood or adolescence. The introduction of drugs that are less toxic and more targeted than those currently used necessitates a partnership between clinical and translational researchers, the pharmaceutical industry, drug regulators, and patients and their families. This therapeutic alliance will ensure that efforts are focused on the unmet clinical needs of young people with cancer. Most children with cancer live in low-income and middle-income countries, and these countries account for 94% of all deaths from cancer in people aged 0–14 years. The immediate priority for these children is to improve access to an affordable, best standard of care in each country. Every country should have a national cancer plan that recognises the unique demographic characteristics and care needs of young people with cancer. Centralisation of the complex components of treatment of these rare diseases is essential to improve survival, accelerate research, and train the future specialist workforce. Referral routes and care pathways must take account of the large geographical distances between many patients' homes and treatment centres, and the economic, cultural, and linguistic diversity of the populations served.
This 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.
Incidence 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.
Childhood 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.
When 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.
The Research to Accelerate Cures and Equity (RACE) for Children Act requires an assessment of molecular targets relevant to pediatric cancer. Due to the biological complexity, candidate molecular ...targets have been primarily evaluated based on single features such as the presence of mutations or deregulated expression. As the understanding of tumor biology evolves, the relevance of certain molecular targets may need to be assessed at isoform and/or mutation variant level to optimize tailored therapeutic interventions.
The discovery and development of anticancer drugs for pediatric patients have historically languished when compared to both past and recent activity in drug development for adult patients, notably ...the dramatic spike of targeted and immune-oncology therapies. The reasons for this difference are multifactorial. Recent changes in the regulatory landscape surrounding pediatric cancer drug development and the understanding that some pediatric cancers are driven by genetic perturbations that also drive disparate adult cancers afford new opportunities. The unique cancer-initiating events and dependencies of many pediatric cancers, however, require additional pediatric-specific strategies. Research efforts to unravel the underlying biology of pediatric cancers, innovative clinical trial designs, model-informed drug development, extrapolation from adult data, addressing the unique considerations in pediatric patients, and use of pediatric appropriate formulations, should all be considered for efficient development and dosage optimization of anticancer drugs for pediatric patients.
Minimal residual disease (MRD) refers to the presence of disease in cases deemed to be in complete remission by conventional pathologic analysis. Assessing the association of MRD status following ...induction therapy in patients with acute lymphoblastic leukemia (ALL) with relapse and mortality may improve the efficiency of clinical trials and accelerate drug development.
To quantify the relationships between event-free survival (EFS) and overall survival (OS) with MRD status in pediatric and adult ALL using publications of clinical trials and other databases.
Clinical studies in ALL identified via searches of PubMed, MEDLINE, and clinicaltrials.gov.
Our search and study screening process adhered to the PRISMA Guidelines. Studies that addressed EFS or OS by MRD status in patients with ALL were included; reviews, abstracts, and studies with fewer than 30 patients or insufficient MRD description were excluded.
Study sample size, patient age, follow-up time, timing of MRD assessment (postinduction or consolidation), MRD detection method, phenotype/genotype (B cell, T cell, Philadelphia chromosome), and EFS and OS. Searches of PubMed and MEDLINE identified 566 articles. A parallel search on clinicaltrials.gov found 67 closed trials and 62 open trials as of 2014. Merging results of 2 independent searches and applying exclusions gave 39 publications in 3 arms of patient populations (adult, pediatric, and mixed). We performed separate meta-analyses for each of these 3 subpopulations.
The 39 publications comprised 13 637 patients: 16 adult studies (2076 patients), 20 pediatric (11 249 patients), and 3 mixed (312 patients). The EFS hazard ratio (HR) for achieving MRD negativity is 0.23 (95% Bayesian credible interval BCI 0.18-0.28) for pediatric patients and 0.28 (95% BCI, 0.24-0.33) for adults. The respective HRs in OS are 0.28 (95% BCI, 0.19-0.41) and 0.28 (95% BCI, 0.20-0.39). The effect was similar across all subgroups and covariates.
The value of having achieved MRD negativity is substantial in both pediatric and adult patients with ALL. These results are consistent across therapies, methods of and times of MRD assessment, cutoff levels, and disease subtypes. Minimal residual disease status warrants consideration as an early measure of disease response for evaluating new therapies, improving the efficiency of clinical trials, accelerating drug development, and for regulatory approval. A caveat is that an accelerated approval of a particular new drug using an intermediate end point, such as MRD, would require confirmation using traditional efficacy end points.
Pediatric acute lymphoblastic leukemia (ALL) is a heterogeneous disease consisting of distinct clinical and biological subtypes that are characterized by specific chromosomal abnormalities or gene ...mutations. Mutation of genes encoding tyrosine kinases is uncommon in ALL, with the exception of Philadelphia chromosome-positive ALL, where the t(9,22)(q34;q11) translocation encodes the constitutively active BCR-ABL1 tyrosine kinase. We recently identified a poor prognostic subgroup of pediatric BCR-ABL1-negative ALL patients characterized by deletion of IKZF1 (encoding the lymphoid transcription factor IKAROS) and a gene expression signature similar to BCR-ABL1-positive ALL, raising the possibility of activated tyrosine kinase signaling within this leukemia subtype. Here, we report activating mutations in the Janus kinases JAK1 (n = 3), JAK2 (n = 16), and JAK3 (n = 1) in 20 (10.7%) of 187 BCR-ABL1-negative, high-risk pediatric ALL cases. The JAK1 and JAK2 mutations involved highly conserved residues in the kinase and pseudokinase domains and resulted in constitutive JAK-STAT activation and growth factor independence of Ba/F3-EpoR cells. The presence of JAK mutations was significantly associated with alteration of IKZF1 (70% of all JAK-mutated cases and 87.5% of cases with JAK2 mutations; P = 0.001) and deletion of CDKN2A/B (70% of all JAK-mutated cases and 68.9% of JAK2-mutated cases). The JAK-mutated cases had a gene expression signature similar to BCR-ABL1 pediatric ALL, and they had a poor outcome. These results suggest that inhibition of JAK signaling is a logical target for therapeutic intervention in JAK mutated ALL.
Background
Pediatric anticancer drug development has numerous challenges. The Pediatric Research Equity Act (PREA) and the Best Pharmaceuticals for Children Act (BPCA) were passed to address ...pediatric drug development deficiencies in general. Until recently, the requirements for pediatric evaluation of most oncology products developed for adult cancers have been waived. Because children typically do not have the same type of cancers, which occur commonly in adults, or the indication or drug had been granted an orphan designation, PREA therefore has had no impact. Pediatric studies for labeling updates are largely done through BPCA by a written request (WR) issued by the Food and Drug Administration (FDA). Because the cancers that occur in pediatric and adult populations do not share the same etiology or natural history, there are limited opportunities to extrapolate adult efficacy and safety to the pediatric population. The characteristics of individual pediatric studies included in WRs have varied greatly over time.
Procedure
In this study, we searched WRs that were issued by the FDA since 2001. We found 40 such requests issued for oncology drugs and biologics, which had been accepted by sponsors.
Results
Clinical trials included in 23 of the WRs have been concluded, 19 have resulted in exclusivity, and three drugs that were studied have been approved for use in pediatric populations. Herein, we present the spectrum of WRs from a regulatory, study design, dosing, formulation, analysis plan, evidentiary standard of efficacy, and safety perspective.
Conclusions
This provides information on requests issued in the past nearly 20 years and studies that are completed. As WRs have provided the only regulatory mechanism to assure pediatric cancer drug development, this can potentially provide insight on how pediatric cancer drug development may change in the future.