SERVICES. USA \\MENT OF HEALTH & HUMAN
Published in final edited form as: Pediatr Blood Cancer. 2026 February ; 73(2): e32164. doi:10.1002/pbc.32164.
Factors associated with rare pediatric cancer trial enrollment: a report from the Children’s Oncology Group Rare Tumors Committee
Brian R. Englum1, Jin Piao2, Lindsay Younis2, Reto M. Baertschiger3, Kenneth S. Chen4, Emily Christison-Lagay5, Hetal Dholaria6, Robyn Gartrell7, M. John Hicks8, Junne Kamihara9, Sarah G. Mitchell10, Manuela Orjuela-Grimm11, Farzana Pashankar5, Samara L. Potter12, Jennifer H. Aldrink 13, Jeremy Rosenblum14, Michael R. Sargen15, Kris Ann P. Schultz16, Brittani K.N. Seynnaeve 17, Mary Wedekind15, Theodore W. Laetsch 18
1.Division of Pediatric Surgery, University of Maryland School of Medicine, Surgery, Baltimore, MD, USA
2.Children’s Oncology Group, Los Angeles, CA, USA
3.Division of Pediatric Surgery, Dartmouth Health Children’s Hospital, Department of Surgery, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
4.Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
5. Yale University School of Medicine, New Haven, CT, USA
6.Perth Children’s Hospital, WA Kids Cancer Centre, The Kids Research Institute, and the University of Western Australia, Perth, Australia
7. Johns Hopkins University School of Medicine, Baltimore, MD, USA
8. Texas Children’s Hospital and Baylor College of Medicine, Houston, TX, USA
9.Department of Pediatric Oncology, Dana-Farber/Boston Children’s Cancer and Blood Disorders Center, Harvard Medical School, Boston, MD, USA
10. Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Department of Pediatric Hematology/Oncology, Emory University School of Medicine, Atlanta, GA, USA
11.Departments of Epidemiology and Pediatrics, Columbia University Medical Center, New York City, NY, USA
12. The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, OH, USA
Corresponding author: Dr. Brian Englum, Department of Surgery, University of Maryland School of Medicine, 29 South Greene Street, Suite 110, Baltimore, MD 21201, USA, benglum@som.umaryland.edu.
*Presented at SIOP Oct. 17-20, 2024. Englum B, Piao J, Younis L, et al. Abstracts: Comparing Children’s Oncology Group Trial Enrollment in Rare Pediatric Cancers to the Seer Cancer Registry. Pediatr Blood Cancer. 2024;71(S3):e31444.
Disclosure
13.Division of Pediatric Surgery, Department of Surgery, Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, OH.
14.New York Medical College, Valhalla, NY, USA
15. Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
16.Children’s Minnesota, Minneapolis, MN, USA
17.Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
18.Division of Oncology, Children’s Hospital of Philadelphia/University of Pennsylvania, Philadelphia, PA, USA
Abstract
Background: Over 90% of US children with cancer are treated at Children’s Oncology Group (COG) centers, who seek to maximize enrollment in therapeutic and biobanking studies. Rare cancers have demonstrated lower than expected COG enrollment. We evaluated trends in COG rare cancer enrollment compared to US incidence from Surveillance, Epidemiology, and End Results (SEER) registries, examining the impact of COG therapeutic trials and Project:EveryChild, a cancer biobank/registry.
Procedure: COG and SEER data from 2002-2020 were queried for US patients <18 years old with adrenocortical carcinoma (ACC), nasopharyngeal carcinoma (NPC), retinoblastoma (RB), thyroid carcinoma, and melanoma. We compared demographic data between COG and SEER, extrapolating incidence for each cancer to analyze trends in COG enrollment.
Results: Patient characteristics, including age, sex, and race, were similar between COG (n=2,184) and SEER (n=5,514). COG enrollment for rare cancers remained low (11%). Initiating Project:EveryChild did not increase enrollment (12% pre- vs. 8% post-Project:EveryChild, p<0.01). For cancers with available therapeutic trial (ACC, NPC, and RB), COG enrollment was higher during trial accrual (40%) than when no trial was open (12%; p<0.01). Patient geography and income did not appear as barriers to COG enrollment.
Conclusions: Although children with rare cancers enrolled in COG studies reflect the US population, enrollment to the COG registry/biospecimen repository continues to be limited in the absence of therapeutic trials, impacting data and biospecimens available to inform therapeutic trial development. Expansion of therapeutic trials or free molecular testing through the Molecular Characterization Initiative may increase data and biospecimens for these rare cancers.
Keywords
Pediatric cancer; rare disease; trial enrollment
1. Introduction
Rare diseases face unique challenges to inclusion in clinical trials. Infrequency of cases results in limited understanding of disease history and paucity of preclinical models,
Pediatr Blood Cancer. Author manuscript; available in PMC 2026 March 30.
making interventional studies difficult to plan and fund. This pattern perpetuates difficulty discovering new information and overcoming limited knowledge hampering progress. Despite limited numbers of children with cancer, cooperative trial groups have shown remarkable success enrolling patients and improving outcomes for pediatric cancers.1-4 While greater than 90% of children with cancer in the United States (US) are treated at Children’s Oncology Group (COG) affiliated institutions5 and individual therapeutic studies of rare tumors have successfully accrued within COG,6,7 previous analyses of COG registry data for thyroid carcinoma, melanoma, nasopharyngeal carcinoma (NPC), and adrenocortical carcinoma (ACC) demonstrated that enrollment was limited to only 7% of the eligible US population.8 In contrast, 50-60% of children with an available clinical trial are enrolled on COG studies in the US, including 59% of children with leukemia, 65% of children with neuroblastoma, and 67% of children with renal tumors.4,9 Moreover, prior studies have raised concerns about underrepresentation of adolescents and certain racial and ethnic groups in COG trials, which may bias future research and treatment protocols against these groups, further impacting enrollment.8,10,11
While COG has maintained a registry of all patients enrolled on COG studies since its creation in 2000,9 APEC14B1 Project:EveryChild12,13 is a collaboration initiated in 2015 between COG and the National Cancer Institute (NCI) to create a biobanking cancer registry available to all pediatric cancers. APEC14B1 aims to generate a catalog for biobanking specimens and associated clinical data to promote the study and understanding of all pediatric cancers, including rare tumors.8,10,11
The COG Rare Tumors Committee evaluated the number of rare tumors being enrolled within COG initiatives and identified patient and disease factors associated with COG enrollment by comparing the population enrolled in COG to the Surveillance, Epidemiology, and End Results (SEER) registry.14 We hypothesized that rare tumor enrollment in COG studies would increase following initiation of APEC14B1.
2. Methods
2.1. Data sources
SEER registry is an NCI-based cancer surveillance program which collects and publishes cancer incidence and survival from population-based registries covering approximately 26.5% of the US population (SEER 17).14-16
At the COG’s creation in 2000, patient data from several pediatric cancer research groups were combined to create a unified registry from all therapeutic trials and other studies. This comprehensive registry captures demographic and tumor data. Throughout this study, we refer to the COG registry, indicating consent-based enrollment in any COG study (therapeutic or non-therapeutic). Non-therapeutic COG registry enrollment has been available for all cancers during the study period through various mechanisms, including the Childhood Cancer Research Network started in 2008 and APEC14B1 since 2015. COG study enrollment is available through nearly 200 COG member institutions in the US; however, not every COG site opens every COG study.5 Because both therapeutic study and registry enrollment require consent by a COG member, patients treated by non-COG
providers may not be offered enrollment unless a mechanism to refer such patients has been established at the treating institution. We refer to therapeutic trial enrollment for patients in COG therapeutic trials, regardless of participation in biobanking or other non-therapeutic studies. APEC14B1 enrollment indicates consent and enrollment in the Project:EveryChild biobanking and registry study, which may be in combination with therapeutic studies. Some patients are placed in the COG database without consent for a specific study. These patients were excluded.
2.2. Inclusion and Exclusion Criteria
We included all US patients enrolled in the COG or SEER 17 registries from 2002 to 2020 (November 2022 submission) who were <18 years of age at the time of their original cancer diagnosis and had one of the following cancers: 1) ACC, 2) NPC, 3) retinoblastoma (RB), 4) thyroid carcinoma, or 5) melanoma. The definition of rare disease varies between different governments and organizations in North America, Europe, and Asia, from an incidence of <2 cases per million to <4-6 cases per 10,000.17-20 Herein, we use the COG qualitative definition of rare tumors, which includes the International Classification of Childhood Cancer (ICCC) subgroup V (retinoblastoma) and XI (epithelial neoplasms and melanoma). Cancers were determined using ICD-O-3 (International Classification of Disease for Oncology, 3rd edition) histology and location codes defined by the ICCC.21
2.3. Data collected
For each incident cancer, we identified the year of diagnosis, age at diagnosis, sex, race and ethnicity of the patient. Household income was assigned as the median household income in the patient’s zip code using data from the US Census Bureau and grouped based on prior studies.22-24 Geographic location (urban, suburban, or rural) was based on patient Federal Information Processing System (FIPS) code and the National Center for Health Statistics classification,25 with large central metro areas classified as urban, large fringe metro areas as suburban, and other areas as rural.26
2.4. Statistical analysis
Demographic data were compared between the COG and SEER datasets for each cancer type. We used frequency and percentages to compare groups, and statistically significant differences were identified using Pearson’s Chi-square test or Fisher’s exact test, as appropriate. Patients with demographic data that was missing or listed as “unknown” were included in table frequency and figures but were excluded from percentage and p-value calculations.
The absolute number of cases per year in the US were estimated from SEER for each cancer type. SEER only covers a portion of the US, so it was necessary to calculate an extrapolated count of cases for the entire US population. Annual incidence rates specific to the combination of age, gender, race, and ethnicity were applied to the U.S. population estimates for each study year to calculate extrapolated counts. By cancer type, we plotted the estimated number per year in the US against the number enrolled per year in COG and APEC14B1. We also plotted the COG annual enrollment for each cancer as a percentage of the estimated US incidence of that cancer. Annual incidence estimates, especially for very
rare diagnoses might be unstable, so 5-year rolling incidence estimates were reported for SEER. Because we were interested in year-on-year changes in COG enrollment around the time of therapeutic trials or APEC14B1 initiation, we did not use 5-year rolling estimates for COG enrollment.
Two-tailed P-values of <0.05 were considered statistically significant. All analyses were performed with R 4.3.3.
3. Results
3.1. Enrollment by demographic factors
From 2002 to 2020, 5,514 patients with one of the five cancers analyzed were identified in the SEER database and 2,184 patients in the COG database. Age at diagnosis was similar for ACC, NPC, and RB between databases, while melanoma and thyroid carcinoma patients in COG were significantly younger than in SEER (Table 1). The 15-17-year-old group constituted 51% of the SEER data but only 23% of the COG melanoma cohort. Similarly, the 15-17-year-old group was 59% of the SEER thyroid cohort, but only 44% of the COG cohort.
The percentage of Black individuals was similar between SEER and COG among all cancers examined, while children with RB in COG were less likely to be Asian or Pacific Islander (API) (5%) compared to children in SEER (11%; p<0.01). A similar trend was found in children with thyroid carcinoma, with API children less represented in COG (4%) vs. SEER (10%; p=0.04). Latino patients were less frequent in COG cohorts across cancers, ranging from 8-25%, while SEER included 12-42% Latino patients.
Given that SEER intentionally over-samples the Latino population and specific racial minorities, the extrapolated US incidence of these cancers in SEER was calculated (Table 2). In ACC, Latino patients were less frequent in the COG cohort than the expected US population (21% vs. 36%); however, other cancers showed a similar percentage of Latino patients in the COG cohort and expected US population. Other racial differences also resolved.
The COG cohort contained more patients from lower income areas. Using an annual median household income of $65,000, 44% of the COG ACC cohort was below this level, compared to 32% of the SEER ACC cohort. This trend was observed for all cancer types: NPC 68% vs. 42%, melanoma 44% vs. 26%, thyroid carcinoma 40% vs. 32%, and RB 49% vs. 32% (COG vs SEER, respectively). Rural-urban classifications were less consistent, with ACC, NPC, and thyroid carcinoma showing similar enrollment across regions. The COG melanoma cohort had fewer urban patients (38% of the cohort) compared to the SEER dataset (60%). A similar trend was observed in retinoblastoma.
3.2. Enrollment by availability of therapeutic trials or APEC14B1
When comparing annual COG enrollment to extrapolated US 5-year rolling average incidences of these cancers in SEER, we find that overall COG enrollment for rare cancers remained low at 11% yet was substantially impacted by therapeutic trial availability. For
ACC, the 5-year rolling incidence estimate was between 7 and 23 cases per year while COG enrolled up to 20 patients per year (Figure 1A). NPC demonstrated a US incidence between 24 and 38 cases per year with COG enrolling between 2 and 25 patients per year (Figure 1B). Retinoblastoma estimated an incidence between 231 and 273 cases per year (Figure 1C). When RB therapeutic trials were not available, COG enrollment was less than 50 cases per year, while during periods of trial availability it increased dramatically, peaking at over 150 cases enrolled in COG per year. When examined as a percentage of US RB cases, COG enrollment outside clinical trials was <20%. With therapeutic trial availability, COG RB enrollment increased to above 30%, peaking at 64% (Figure 2C). Notably, availability of therapeutic trials was limited to certain Groups (stages) of retinoblastoma for portions of this period, suggesting that enrollment likely exceeded these proportions among patients eligible for a therapeutic trial. This remained consistent across diagnoses. Cancers with an available therapeutic trial (ACC, NPC, and RB) were significantly more likely to enroll in COG during trial accrual (40%) than when no therapeutic trial was open (12%; p<0.01; Table 3).
In cancers without available therapeutic trials during the study period (thyroid carcinoma and melanoma), COG enrollment was very low (3%). Despite large numbers of available thyroid carcinomas (308-602 cases per year in the US; Figure 1D) and melanomas (221-424 annual cases; Figure 1E), COG enrollment never reached 50 cases per year for either cancer. As a percentage, COG enrollment of patients with thyroid cancer peaked at 5% of available US cases, generally enrolling <3% (Figure 2D). COG enrollment of melanoma peaked at 10% but was generally <5% (Figure 2E).
The introduction of APEC14B1 did not increase enrollment of children with rare cancers (12% pre-APEC14B1 vs. 8% during APEC14B1, p<0.01). For each cancer type evaluated, patients enrolled in APEC14B1 accounted for nearly all cases of these rare cancers enrolled in COG studies after 2015, but APEC14B1 was not associated with an increase in COG enrollment.
4. Discussion
When examining five rare pediatric cancers (ACC, NPC, RB, thyroid carcinoma, and melanoma), COG enrollment generally reflects US demographic case mix but remains very low (11% of US cases). Registry and biobanking efforts through APEC14B1 did not increase COG enrollment of these rare cancers. Conversely, our study demonstrates that COG therapeutic trials of even very rare cancers can accrue a substantial fraction of impacted children across the US.
Prior studies have raised concerns that patients enrolled in pediatric oncology research do not reflect the general population. In one single center study, authors identified decreased enrollment among Latino patients, with 60% lower odds of enrollment compared to non-Latino, White patients.11 A similar COG study showed mixed enrollment disparities but did identify underrepresentation of White males and younger Latino patients.10 Other studies have found an underrepresentation of Black and Latino patients in trials for lymphohematopoietic cancers.10,27 Except for decreased representation of Latino
patients with ACC, we did not find any significant racial or ethnic differences between patients enrolled in COG studies and the expected US population after accounting for SEER oversampling.28 The persistent underrepresentation of Latino patients may suggest underlying challenges to recruiting and enrolling this population, including barriers for patients whose preferred language is not English, as suggested in recent COG and institutional surveys.11,29
Numerous studies have demonstrated underrepresentation of adolescent patients in COG studies,8,10,11 including a previous COG analysis demonstrating 25% of expected patients with thyroid cancer enrolled in COG studies among patients <10 years of age, but only 2.6% enrollment in the 15-19-year-old group. Among patients with melanoma, 14% of the expected enrollment was achieved in cases <10 years of age, and only 2% in the 15- 19-year-old age group. Our study found a similar decrease in thyroid and melanoma case enrollment as patient age increased. Retinoblastoma has very few newly diagnosed patients older than 5 years of age limiting a similar evaluation in this population. However, age distributions that were representative of the larger US incidence were demonstrated in ACC and NPC.
Given the greater experience among adult providers and the smaller percentage of patients requiring systemic medical therapy for thyroid carcinoma and melanoma, we hypothesize that these cancers are often referred to endocrinology, endocrine surgery, dermatology, or surgical oncology providers, often focused on adult patients. These patients may never see pediatric oncology or pediatric surgery, who may provide the only access to COG studies, as adult providers of cancer care are rarely COG members or knowledgeable about available COG protocols. Similarly, early-stage RB is managed primarily by ophthalmic oncologists and is treated at a limited number of centers, decreasing the likelihood that children with retinoblastoma will be offered enrollment in APEC14B1. Prior pediatric- specific, therapeutic trials in ACC and NPC and/or greater use of systemic therapies for these diagnoses, prompting referral to pediatric oncology, may have contributed to the more representative age distribution of COG enrollment. European studies have described similar findings, with rare pediatric cancers like melanoma seen by providers other than pediatric oncologists; these cases are less likely to be captured in pediatric cancer registries.30,31 While the current study is specific to US pediatric oncology research infrastructure and enrollment, similar challenges exist in Europe and likely across all regions engaging these difficult to study diseases.
Few COG studies have focused on the role of socioeconomic status or urban-suburban- rural neighborhood in pediatric oncology study enrollment. Compared to SEER, we identified a consistent overrepresentation of patients from zip codes with an annual median household income of <$65,000, indicating that COG tends to enroll more socioeconomically disadvantaged patients with these five rare cancers. Prior studies have been mixed, with one study showing comparable results of higher COG enrollment among children with acute myeloid leukemia in socially disadvantaged areas and another study showing representative socioeconomic trial enrollment across COG studies.27,32 Urban-rural location trends were less uniform, but COG enrolled more rural patients with RB and melanoma, which is similar to adolescent and young adult patients across a variety of cancers in SEER.33 In both cases,
it is encouraging that any barriers to enrollment from rural geographic setting and lower income appear to be overcome in COG studies, potentially due to the broad geographic reach of the nearly 200 COG sites across the US.
Contrary to our hypothesis that APEC14B1 would improve COG enrollment for rare pediatric cancers, we saw no increase in enrollment with the advent of APEC14B1 in 2015 and beyond. This finding suggests that the addition of cancer biobanking alone is not sufficient to improve COG registry enrollment of rare pediatric cancers. However, we did find that therapeutic trial availability was associated with an enrollment increase of more than 3-fold, from 12% to 40%. More consistent therapeutic trial availability may improve enrollment even further, as the initiation and closing of trials involves periods of lower enrollment. In the overlapping trials for RB, not all patients with RB were eligible throughout the trial period based on their extent of disease. Peak enrollment during the middle of clinical trial availability, the period in which clinical trials are likely to be open at the maximum number of sites, was 60% or higher. These encouraging enrollment successes demonstrate the potential of therapeutic COG trials to add robust data to our understanding of these rare diseases and improve therapeutic options through clinical trials.
The inability to perform clinical trials is a major barrier to advancing pediatric oncology research and improving patient outcomes.34 In the case of rare pediatric tumors, poor enrollment in COG biospecimen registries hinders retrospective studies of therapeutic agents and development of preclinical resources. This limits discovery of novel therapeutic strategies and natural history data, making effect size and accrual difficult to estimate. The lack of these foundational research elements are major barriers to the robust planning and justification needed for future clinical trials with the potential to advance research, treatments, and clinical outcomes for children with rare cancers. A series of collaborative trials has contributed to remarkable progress seen in diseases like acute lymphoblastic leukemia and Wilms tumor despite the low incidence of these pediatric cancers compared with common adult cancers.4,35-39 The COG’s ability to recruit and enroll adequate patients to make these advancements has been a major success story in medicine.3,4 Despite the challenges, patients with rare pediatric cancers deserve similar efforts to improve therapies and outcomes.
The current analysis supports therapeutic trials as a method to increase enrollment, likely due to the perceived benefit of access to a novel and potentially better therapy. During the time period covered by this analysis, there was no direct benefit to patients with rare tumors for participation in the COG registry and biospecimen repository, which may have limited accrual. Access to molecular testing provides a potential benefit, even if the value of testing is not yet fully understood. Part of the NCI’s Childhood Cancer Data Initiative since 2023, the Molecular Characterization Initiative (MCI)40 provides free molecular testing for all rare pediatric tumors through APEC14B1 enrollment. Prognostic information or access to targeted therapies resulting from molecular testing could also promote COG therapeutic trial enrollment.
Incentives and resources must be aligned to optimize enrollment. A lack of resources may be a barrier for institutions when reimbursements do not cover the costs of data and
specimen collection. This barrier may be particularly acute at smaller institutions without the economies of scale of developed research infrastructure at larger academic centers and may lead these institutions to prioritize better funded therapeutic trial enrollment over efforts like APEC14B1. To overcome this barrier, increased funding to sites, as has occurred with the MCI, and exploring methods to decrease burden on sites through automated data capture from the EMR will be critical.41 Alternatively, larger centers may prioritize institutional biobanking efforts that compete with COG and MCI enrollment due to perceived ease of access to specimens. Ensuring that investigators are aware of the available biosamples and a streamlined process to access these may encourage further enrollment.
Efforts need to focus on adolescent and young adult (AYA) patients that are currently poorly enrolled by COG. If poor COG enrollment among AYA patients was correlated with strong enrollment in trials by adult cooperative oncology groups, one might argue that these patients are well served by adult oncology trials. Unfortunately, studies have demonstrated poor enrollment of AYA patients across all oncology clinical trials.42, 43 AYA oncology outcomes have lagged behind improvements in both adult and pediatric populations, including thyroid cancer. These findings have made improved enrollment of underserved AYA populations in clinical trials a priority of both the National Institutes of Health and the Institute of Medicine. 44 46 MCI now allows enrollment for patients up to 25 years of age. We need to engage our non-COG colleagues, including other pediatric providers (e.g., pediatric otolaryngologists or endocrinologists), adult providers caring for these children (e.g., dermatologists or endocrine surgeons), and adult cooperative groups. We must promote the need to improve outcomes for this group of patients, where progress has lagged more common pediatric cancers,47 and the potential direct benefits from molecular testing of the patient’s tumor to encourage and streamline systems for referral and enrollment regardless of the primary oncology provider’s connection to COG.
Efforts that decrease the barriers between these patients, their providers, and COG studies may also bolster enrollment through data linkages,48 EMR or web-based enrollment tools,34 and automated or mandatory reporting mechanisms. Continued relationships with international partners to promote joint protocols will also be needed for multinational enrollment and efficient clinical trials in very rare pediatric cancers.
The current study has clear limitations. The analysis used the SEER database, which limited available data to patients diagnosed from 2002 to 2020 due to a lag in reporting. Given this, enrollment data from COG was also limited to enrollment through 2020. The Molecular Characterization Initiative began after that date, so the present analysis is unable to capture the potential impact of that effort. Even in a robust, population-based dataset such as SEER, the sample size was often too small for stable estimates of specific subgroups. Although we could demonstrate associations between enrollment and several factors, such as availability of a therapeutic trial, causality could not be examined in this retrospective analysis.
5. Conclusion
Despite efforts to improve COG enrollment in studies for rare pediatric malignancies through registry and biobanking opportunities, COG enrollment of these challenging cancers
remains disappointingly low in the absence of a therapeutic trial. COG rare tumor cases generally reflect the US population of these cancers, and this study did not suggest major barriers to enrollment related to race, ethnicity, socioeconomic status, or urban-rural location. New efforts are needed to improve enrollment and provide data and biospecimens for foundational research to inform therapeutic trial development that will advance outcomes for these patients. Novel therapeutic trials, free molecular testing through the Molecular Characterization Initiative, and increased support for the site infrastructure to enroll patients into COG observational and therapeutic studies may increase the availability of data and biospecimens for these rare and difficult to study cancers.
Acknowledgements
Research reported in this publication was supported by the National Cancer Institute of the National Institutes of Health under award numbers U10CA180886 and U10CA180899 to the Children’s Oncology Group. Additional funding was supported by the National Center for Advancing Translational Science (NCATS) award number K12TR004925 (BRE).
Abbreviations:
| ACC | Adrenocortical Carcinoma |
|---|---|
| API | Asian or Pacific Islander |
| AYA | Adolescent and Young Adult |
| COG | Children's Oncology Group |
| FIPS | Federal Information Processing System |
| ICCC | International Classification of Childhood Cancer |
| ICD-O | International Classification of Disease for Oncology |
| MCI | Molecular Characterization Initiative |
| NPC | Nasopharyngeal Carcinoma |
| RB | Retinoblastoma |
| SEER | Surveillance, Epidemiology, and End Results |
| US | United States |
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A. Adrenocortical carcinoma
B. Nasopharyngeal carcinoma
C. Retinoblastoma
50
50
400
45
45
2/2006
11/2013
12/2005
5/2017
350
40
40
35
9/2006
5/2013
35
300
30
30
250
25
25
200
20
20
150
15
15
10
10
100
5
5
50
0
0
0
2005
2010
2015
2020
2005
2010
2015
2020
2005
2010
2015
2020
D. Thyroid Carcinoma
Year
E. Melanoma
Year
Year
700
400
650
COG - PEC - US (based on SEER)
600
350
550
500
300
450
250
400
350
200
300
250
150
200
150
100
100
50
50
0
0
2005
2010
2015
2020
2005
2010
2015
2020
Year
Year
A. Adrenocortical carcinoma
B. Nasopharyngeal carcinoma
C. Retinoblastoma
200%
100%
100%
180%
90%
90%
160%
80%
80%
140%
70%
70%
120%
60%
60%
100%
50%
50%
80%
40%
40%
60%
30%
30%
40%
20%
20%
20%
10%
10%
0%
0%
0%
2005
2010
2015
2020
2005
2010
2015
2020
2005
2010
2015
2020
D. Thyroid Carcinoma
Year
E. Melanoma
Year
Year
10%
100%
9%
90%
COG
PEC
8%
80%
7%
70%
6%
60%
5%
50%
4%
40%
3%
30%
2%
20%
1%
10%
0%
0%
2005
2010
2015
2020
2005
2010
2015
2020
Year
Year
TABLE 1.
Patient Characteristics in SEER and COG
| Adrenocortical carcinomas | Malignant melanomas | Nasopharyngeal carcinomas | Retinoblastoma | Thyroid carcinomas | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| COG SEER (N=121) (N=76) | P- value | COG (N=243) | SEER (N=1476) | P- value | COG (N=205) | SEER (N=164) | P- value | COG (N=1377) | SEER (N=1370) | P- value | COG (N=238) | SEER (N=2428) | P- value | |
| Age category | 0.54 | <0.01 | 0.95 | 0.61 | <0.01 | |||||||||
| <1 year | 12 (10%) 8 (11%) | 6 (2%) | 18 (1%) | 0 (0%) | 0 (0%) | 615 (45%) | 589 (43%) | 0 (0%) | 4 (0%) | |||||
| 1-4 years | 41 (34%) 28 (37%) | 30 (12%) | 84 (6%) | 1 (0%) | 0 (0%) | 719 (52%) | 727 (53%) | 0 (0%) | 21 (1%) | |||||
| 5-9 years | 22 (18%) 7 (9%) | 65 (27%) | 182 (12%) | 13 (6%) | 10 (6%) | 38 (3%) | 45 (3%) | 28 (12%) | 152 (6%) | |||||
| 10-14 years | 29 (24%) 20 (26%) | 86 (35%) | 443 (30%) | 94 (46%) | 72 (44%) | 5 (0%) | 8 (1%) | 105 (44%) | 814 (34%) | |||||
| 15-17 years | 17 (14%) 13 (17%) | 56 (23%) | 749 (51%) | 97 (47%) | 82 (50%) | 0 (0%) | 1 (0%) | 105 (44%) | 1437 (59%) | |||||
| Gender | 0.14 | 0.33 | 0.73 | 0.91 | 0.02 | |||||||||
| Female | 77 (64%) 40 (53%) | 123 (51%) | 799 (54%) | 64 (31%) | 48 (29%) | 685 (50%) | 678 (49%) | 172 (72%) | 1915 (79%) | |||||
| Male | 44 (36%) 36 (47%) | 120 (49%) | 677 (46%) | 141 (69%) | 116 (71%) | 692 (50%) | 692 (51%) | 66 (28%) | 513 (21%) | |||||
| Race | 0.49 | 0.09 | 0.13 | <0.01 | 0.04 | |||||||||
| American Indian/Alaska Native | 4 (4%) 2 (3%) | 1 (0%) | 8 (1%) | 1 (1%) | 1 (1%) | 9 (1%) | 20 (1%) | 3 (1%) | 25 (1%) | |||||
| Asian or Pacific Islander | 2 (2%) 5 (7%) | 2 (1%) | 46 (3%) | 13 (7%) | 17 (10%) | 60 (5%) | 142 (11%) | 9 (4%) | 230 (10%) | |||||
| Black | 6 (6%) 5 (7%) | 8 (3%) | 30 (2%) | 91 (50%) | 63 (38%) | 182 (17%) | 198 (15%) | 14 (7%) | 132 (6%) | |||||
| White | 86 (88%) 64 (84%) | 222 (95%) | 1314 (94%) | 77 (42%) | 83 (51%) | 848 (77%) | 992 (73%) | 175 (87%) | 2007 (84%) | |||||
| Unknown | 23 0 | 10 | 78 | 23 | 0 | 278 | 18 | 37 | 34 | |||||
| Ethnicity | <0.01 | 0.12 | <0.01 | <0.01 | 0.09 | |||||||||
| Non-Latino | 88 (79%) 44 (58%) | 217 1306 (92%) (88%) | 174 125 (88%) (76%) | 981 (76%) 901 (66%) | 165 (75%) | 1687 (69%) | ||||||||
| Latino | 24 (21%) 32 (42%) | 19 (8%) | 170 (12%) | 23 (12%) | 39 (24%) | 304 (24%) | 469 (34%) | 55 (25%) | 741 (31%) | |||||
| Unknown | 9 0 | 7 | 0 | 8 | 0 | 92 | 0 | 18 | 0 | |||||
Author Manuscript
Author Manuscript
Author Manuscript
| Adrenocortical carcinomas | Malignant melanomas | Nasopharyngeal carcinomas | Retinoblastoma | Thyroid carcinomas | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| COG (N=121) | SEER (N=76) | P- value | COG (N=243) | SEER (N=1476) | P- value | COG (N=205) | SEER (N=164) | P- value | COG (N=1377) | SEER (N=1370) | P- value | COG (N=238) | SEER (N=2428) | P- value | |
| Household income | 0.03 | <0.01 | <0.01 | <0.01 | <0.01 | ||||||||||
| < $50,000 | 17 (14%) | 12 (16%) | 37 (15%) | 104 (7%) | 79 (39%) | 17 (10%) | 312 (23%) | 129 (9%) | 33 (14%) | 207 (9%) | |||||
| $50,000 - $64,999 | 35 (30%) | 12 (16%) | 70 (29%) | 273 (19%) | 60 (29%) | 52 (32%) | 351 (26%) | 315 (23%) | 63 (26%) | 558 (23%) | |||||
| $65,000 - $74,999 | 16 (14%) | 22 (29%) | 42 (17%) | 413 (28%) | 21 (10%) | 48 (29%) | 200 (15%) | 430 (31%) | 37 (16%) | 653 (27%) | |||||
| $75,000 + | 50 (42%) | 30 (39%) | 94 (39%) | 685 (46%) | 44 (22%) | 47 (29%) | 503 (37%) | 496 (36%) | 105 (44%) | 1010 (42%) | |||||
| Unknown | 3 | 0 | 0 | 1 | 1 | 0 | 11 | 0 | 0 | 0 | |||||
| Geographic location | 0.15 | <0.01 | 0.32 | <0.01 | 0.59 | ||||||||||
| Urban | 60 (50%) | 48 (64%) | 93 (38%) | 881 (60%) | 114 (56%) | 92 (56%) | 752 (55%) | 819 (60%) | 139 (58%) | 1458 (60%) | |||||
| Suburban | 37 (31%) | 18 (24%) | 107 (44%) | 445 (30%) | 54 (26%) | 51 (31%) | 403 (29%) | 416 (30%) | 77 (32%) | 711 (29%) | |||||
| Rural | 23 (19%) | 9 (12%) | 43 (18%) | 147 (10%) | 37 (18%) | 21 (13%) | 215 (16%) | 133 (10%) | 22 (9%) | 253 (10%) | |||||
| Unknown | 1 | 1 | 0 | 3 | 0 | 0 | 7 | 2 | 0 | 6 | |||||
Note: Percentages and p-values do not include “unknown” categories. COG -Children’s Oncology Group; SEER -Surveillance, Epidemiology, and End Results
| Adrenocortical carcinomas | Malignant melanomas | Nasopharyngeal carcinomas | Retinoblastoma | Thyroid carcinomas | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| COG (N=121) | US (N=238) | COG (N=243) | US (N=6280) | COG (N=205) | US (N=593) | COG US (N=1377) (N=4840) | COG US (N=238) (N=8271) | |||
| Race | ||||||||||
| American Indian/Alaska Native | 4 (4%) | 0 (0%) | 1 (0%) | 11 (0%) | 1 (1%) | 0 (0%) | 9 (1%) | 67 (1%) | 3 (1%) | 81 (1%) |
| Asian or Pacific Islander | 2 (2%) | 5 (2%) | 2 (1%) | 82 (1%) | 13 (7%) | 30 (5%) | 60 (5%) | 260 (5%) | 9 (4%) 416 (5%) | |
| Black | 6 (6%) | 9 (4%) | 8 (3%) | 108 (2%) | 91 (50%) | 258 (44%) | 182 (17%) | 854 (18%) | 14 (7%) 476 (6%) | |
| White | 86 (88%) | 224 (94%) | 222 (95%) | 6079 (97%) | 77 (42%) | 305 (51%) | 848 (77%) | 3659 (76%) | 175 (87%) 7298 (88%) | |
| Unknown | 23 | 0 | 10 | 0 | 23 | 0 | 278 | 0 | 37 0 | |
| Ethnicity | ||||||||||
| Non-Latino | 88 (79%) | 152 (64%) | 217 (92%) | 5850 (93%) | 174 (88%) | 505 (85%) | 981 (76%) | 3629 (75%) | 165 (75%) 6553 (79%) | |
| Latino | 24 (21%) | 86 (36%) | 19 (8%) | 430 (7%) | 23 (12%) | 88 (15%) | 304 (24%) | 1211 (25%) | 55 (25%) 1718 (21%) | |
| Unknown | 9 | 0 | 7 | 0 | 8 | 0 | 92 | 0 | 18 0 | |
Note: Percentages do not include “unknown” categories. COG -Children’s Oncology Group, indicates patients enrolled in COG study; US -United States, indicates expected population extrapolated from SEER.
| Disease Type | Pre-APEC14B1 (%) | Post-APEC14B1" (%) | P-value | Therapeutic trial available (%) | No therapeutic trial available (%) | P-value |
|---|---|---|---|---|---|---|
| Overall | 12 | 8 | <0.01 | 40 | 12 | <0.01 |
| Adrenocortical carcinomas | 50 | 33 | 0.12 | 86 | 21 | <0.01 |
| Nasopharyngeal carcinomas | 36 | 24 | 0.04 | 49 | 19 | <0.01 |
| Retinoblastoma | 32 | 20 | <0.01 | 38 | 9 | <0.01 |
| Malignant melanomas | 4 | 4 | 0.6 | NA | NA | NA |
| Thyroid carcinomas | 3 | 3 | 0.69 | NA | NA | NA |
* Post-APEC14B1 denotes patients enrolled in COG after initiation of APEC14B1 in 2015.