Ethnic and racial differences in patients with Ewing sarcoma

Sarcoma incidence worldwide: regional differences in histology and molecular subtypes

PURPOSE OF REVIEW

There are numerous sarcoma subtypes and vary widely in terms of epidemiology, clinical characteristics, genetic profiles, and pathophysiology. They also differ widely between ethnic groups. This review focuses on the different incidence rates of sarcomas in different regions and the potential explanations for these disparities.

RECENT FINDINGS

In an intercontinental study using national cancer registry databases from France and Taiwan, the French population had a higher risk of liposarcomas, leiomyosarcomas, and synovial sarcomas, whereas the Taiwanese population had a higher incidence of angiosarcomas and malignant peripheral nerve sheath tumors. The anatomical distribution of these sarcomas also varied between these two regions. In France, most angiosarcoma cases occurred in the extremities and trunk, whereas in Taiwan, angiosarcoma cases in the abdomen and pelvis were more common. Another international study showed that in addition to the common known TP53 and NF1 germline mutations, genes involved in centromere and telomere maintenance were also involved in sarcomagenesis. We reviewed factors related to genetics, environmental effects, chemical exposure, and radiation exposure that could explain the differences in sarcoma incidence among different geographical or ethnic regions.

SUMMARY

Our understanding of the potential cause of sarcomas with different subtypes is limited. Establishing a comprehensive global database for patients with sarcomas from all ethnic groups is essential to deepen our understanding of the potential risk factors and the pathophysiology of all sarcoma subtypes.

Disparities in incidence and survival for patients with Ewing sarcoma in Florida

BACKGROUND

Ewing sarcoma (ES) is a malignant bone tumor most commonly affecting non-Hispanic White (NHW) adolescent males, though recognition among Hispanic individuals is rising. Prior population-based studies in the United States (US), utilizing Surveillance, Epidemiology, and End Results (SEER) have shown higher all-cause mortality among White Hispanics, Blacks, and those of low socioeconomic status (SES). Florida is not part of SEER but is home to unique Hispanic populations including Cubans, Puerto Ricans, South Americans that contrasts with the Mexican Hispanic majority in other US states. This study aimed to assess racial/ethnic disparities on incidence and survival outcomes among this diverse Florida patient population.

METHODOLOGY

Our study examined all patients diagnosed with osseous ES (2005-2018) in Florida (n = 411) based on the state's population-based cancer registry dataset. Florida Age-adjusted Incidence Rates (AAIRs) were computed by sex and race-ethnicity and compared to the equivalent populations in SEER. Cause-specific survival disparities among Florida patients were examined using Kaplan-Meier analysis. Univariable and multivariable analyses using Cox regression were performed for race/ethnicity, with adjustment for age, sex, year of diagnosis, site of disease, staging, SES, and insurance type.

RESULTS

There was a significantly higher incidence of osseous ES in Florida Hispanic males (AAIR 2.6/1,000,000); (95% CI: 2.0-3.2 per 1,000,000; n = 84) compared to the SEER Hispanic males (AAIR 1.2/1,000,000;1.1-1.4 per 1,000,000; n = 382). Older age, distant metastasis, lack of chemotherapy or surgical resection were statistically significant determinants of poor survival while SES, insurance status and race-ethnicity were not. However, among nonmetastatic ES, Florida Hispanics had an increased risk of death compared to Florida NHW (adjusted Hazard Ratio 2.32; 95%CI: 1.20-4.46; p = 0.012).

CONCLUSIONS

Florida Hispanic males have a higher-than-expected incidence of osseous ES compared to the US. Hispanics of both sexes show remarkably worse survival for nonmetastatic disease compared to NHW. This disparity is likely multifactorial and requires further in-depth studies.

Pediatric oncology drug development and dosage optimization

Oncology drug discovery and development has always been an area facing many challenges. Phase 1 oncology studies are typically small, open-label, sequential studies enrolling a small sample of adult patients (i.e., 3-6 patients/cohort) in dose escalation. Pediatric evaluations typically lag behind the adult development program. The pediatric starting dose is traditionally referenced on the recommended phase 2 dose in adults with the incorporation of body size scaling. The size of the study is also small and dependent upon the prevalence of the disease in the pediatric population. Similar to adult development, the dose is escalated or de-escalated until reaching the maximum tolerated dose (MTD) that also provides desired biological activities or efficacy. The escalation steps and identification of MTD are often rule-based and do not incorporate all the available information, such as pharmacokinetic (PK), pharmacodynamic (PD), tolerability and efficacy data. Therefore, it is doubtful if the MTD approach is optimal to determine the dosage. Hence, it is important to evaluate whether there is an optimal dosage below the MTD, especially considering the emerging complexity of combination therapies and the long-term tolerability and safety of the treatments. Identification of an optimal dosage is also vital not only for adult patients but for pediatric populations as well. Dosage-finding is much more challenging for pediatric populations due to the limited patient population and differences among the pediatric age range in terms of maturation and ontogeny that could impact PK. Many sponsors defer the pediatric strategy as they are often perplexed by the challenges presented by pediatric oncology drug development (model of action relevancy to pediatric population, budget, timeline and regulatory requirements). This leads to a limited number of approved drugs for pediatric oncology patients. This review article provides the current regulatory landscape, incentives and how they impact pediatric drug discovery and development. We also consider different pediatric cancers and potential clinical trial challenges/opportunities when designing pediatric clinical trials. An outline of how quantitative methods such as pharmacometrics/modelling & simulation can support the dosage-finding and justification is also included. Finally, we provide some reflections that we consider helpful to accelerate pediatric drug discovery and development.

Birth characteristics and risk of Ewing sarcoma

PURPOSE

The incidence of Ewing sarcoma varies according to race and ethnicity, and genetic susceptibility is known to affect disease risk. Apart from these factors, the etiology of Ewing sarcoma is largely unknown.

METHODS

We compared the birth characteristics of a population-based series of 556 Ewing sarcoma cases born in California in 1978-2015 and diagnosed in 1988-2015 with those of 27,800 controls selected from statewide birth records and frequency-matched to cases on the year of birth, using multivariable logistic regression models. We also assessed whether Ewing sarcoma clustered within families.

RESULTS

Compared to non-Hispanic White subjects, Black (odds ratio [OR] = 0.07, 95% confidence interval [CI] 0.03-0.18), Asian (OR = 0.57, 95% CI 0.41-0.80), and Hispanic (OR = 0.73, 95% CI 0.62-0.88) individuals had a significantly lower risk of Ewing sarcoma. Race and ethnicity differences were more profound for metastatic Ewing sarcoma. Birthweight was also identified as a significant risk factor (OR = 1.09, 95% CI 1.00-1.18 for each 500 g increase in birthweight). A separate family-based cancer clustering analysis did not suggest any strong role for familial predisposition alleles.

CONCLUSIONS

This population-based study with minimal selection bias provides support for a role of accelerated fetal growth in the etiology of Ewing sarcoma in addition to more precise estimates of racial and ethnic variations in disease risk. This comparatively large analysis of birth characteristics and Ewing sarcoma in a multiethnic population should stimulate further investigations into genetic and environmental causes.

Socioeconomic disparities in musculoskeletal oncology

Musculoskeletal oncology is a clinical specialty dealing with a diverse population of patients with metastatic bone disease, hematological malignancies with musculoskeletal manifestations, primary bone malignancies and soft tissue sarcomas. There are wide-spread disparities including socioeconomic (SES) and insurance-related disparities reported in the literature. In this review, we'll summarize the disparities surrounding the musculoskeletal oncology.

The adaptive evolution of cancer driver genes

BACKGROUND

Cancer is a life-threatening disease in humans; yet, cancer genes are frequently reported to be under positive selection. This suggests an evolutionary-genetic paradox in which cancer evolves as a secondary product of selection in human beings. However, systematic investigation of the evolution of cancer driver genes is sparse.

RESULTS

Using comparative genomics analysis, population genetics analysis and computational molecular evolutionary analysis, the evolution of 568 cancer driver genes of 66 cancer types were evaluated at two levels, selection on the early evolution of humans (long timescale selection in the human lineage during primate evolution, i.e., millions of years), and recent selection in modern human populations (~ 100,000 years). Results showed that eight cancer genes covering 11 cancer types were under positive selection in the human lineage (long timescale selection). And 35 cancer genes covering 47 cancer types were under positive selection in modern human populations (recent selection). Moreover, SNPs associated with thyroid cancer in three thyroid cancer driver genes (CUX1, HERC2 and RGPD3) were under positive selection in East Asian and European populations, consistent with the high incidence of thyroid cancer in these populations.

CONCLUSIONS

These findings suggest that cancer can be evolved, in part, as a by-product of adaptive changes in humans. Different SNPs at the same locus can be under different selection pressures in different populations, and thus should be under consideration during precision medicine, especially for targeted medicine in specific populations.

Feasibility and Toxicity of Interval-Compressed Chemotherapy in Asian Children and Young Adults with Sarcoma

Twelve Asian patients with sarcoma received interval-compressed (ic-) chemotherapy scheduled every 14 days with a regimen of vincristine (2 mg/m²), doxorubicin (75 mg/m²), and cyclophosphamide (1200-2200 mg/m²) (VDC) alternating with a regimen of ifosfamide (9000 mg/m²) and etoposide (500 mg/m²) (IE), with filgrastim (5-10 mcg/kg/day) between cycles. Carboplatin (800 mg/m²) was added for CIC-rearranged sarcoma. The patients were treated with 129 cycles of ic-VDC/IE with a median interval of 19 days (interquartile range [IQR], 15-24 days. Median nadirs (IQR) were neutrophil count, 134 (30-396) × 10⁶/L at day 11 (10-12), recovery by day 15 (14-17) and platelet count, 35 (23-83) × 10⁹/L at day 11 (10-13), recovery by day 17 (14-21). Fever and bacteremia were observed in 36% and 8% of cycles, respectively. The diagnoses were Ewing sarcoma (6), rhabdomyosarcoma (3), myoepithelial carcinoma (1), malignant peripheral nerve sheath tumor (1), and CIC-DUX4 Sarcoma (1). Seven of the nine patients with measurable tumors responded (one CR and six PR). Interval-compressed chemotherapy is feasible in the treatment of Asian children and young adults with sarcomas.

Perinucleolar Compartment (PNC) Prevalence as an Independent Prognostic Factor in Pediatric Ewing Sarcoma: A Multi-Institutional Study

The perinucleolar compartment (PNC) is a small nuclear body that plays important role in tumorigenesis. PNC prevalence correlates with poor prognosis and cancer metastasis. Its expression in pediatric Ewing sarcoma (EWS) has not previously been documented. In this study, we analyzed 40 EWS tumor cases from Caucasian and Hispanic patients for PNC prevalence by immunohistochemical detection of polypyrimidine tract binding protein and correlated the prevalence with dysregulated microRNA profiles. EWS cases showed staining ranging from 0 to 100%, which were categorized as diffuse (≥77%, n = 9, high PNC) or not diffuse (<77%, n = 31) for low PNC. High PNC prevalence was significantly higher in Hispanic patients from the US (n = 6, p = 0.017) and in patients who relapsed with metastatic disease (n = 4; p = 0.011). High PNC was associated with significantly shorter disease-free survival and early recurrence compared to those with low PNC. Using NanoString digital profiling, high PNC tumors revealed upregulation of eight and downregulation of 18 microRNAs. Of these, miR-320d and miR-29c-3p had the most significant differential expression in tumors with high PNC. In conclusion, this is the first study that demonstrates the presence of PNC in EWS, reflecting its utility as a predictive biomarker associated with tumor metastasis, specific microRNA profile, Hispanic ethnic origin, and poor prognosis.

Targeted long-read sequencing of the Ewing sarcoma 6p25.1 susceptibility locus identifies germline-somatic interactions with EWSR1-FLI1 binding

Ewing sarcoma (EwS) is a rare bone and soft tissue malignancy driven by chromosomal translocations encoding chimeric transcription factors, such as EWSR1-FLI1, that bind GGAA motifs forming novel enhancers that alter nearby expression. We propose that germline microsatellite variation at the 6p25.1 EwS susceptibility locus could impact downstream gene expression and EwS biology. We performed targeted long-read sequencing of EwS blood DNA to characterize variation and genomic features important for EWSR1-FLI1 binding. We identified 50 microsatellite alleles at 6p25.1 and observed that EwS-affected individuals had longer alleles (>135 bp) with more GGAA repeats. The 6p25.1 GGAA microsatellite showed chromatin features of an EWSR1-FLI1 enhancer and regulated expression of RREB1, a transcription factor associated with RAS/MAPK signaling. RREB1 knockdown reduced proliferation and clonogenic potential and reduced expression of cell cycle and DNA replication genes. Our integrative analysis at 6p25.1 details increased binding of longer GGAA microsatellite alleles with acquired EWSR-FLI1 to promote Ewing sarcomagenesis by RREB1-mediated proliferation.

Is the Number of National Database Research Studies in Musculoskeletal Sarcoma Increasing, and Are These Studies Reliable?

BACKGROUND

Large national databases have become a common source of information on patterns of cancer care in the United States, particularly for low-incidence diseases such as sarcoma. Although aggregating information from many hospitals can achieve statistical power, this may come at a cost when complex variables must be abstracted from the medical record. There is a current lack of understanding of the frequency of use of the Surveillance, Epidemiology, and End Results (SEER) database and the National Cancer Database (NCDB) over the last two decades in musculoskeletal sarcoma research and whether their use tends to produce papers with conflicting findings.

QUESTIONS/PURPOSES

(1) Is the number of published studies using the SEER and NCDB databases in musculoskeletal sarcoma research increasing over time? (2) What are the author, journal, and content characteristics of these studies? (3) Do studies using the SEER and the NCDB databases for similar diagnoses and study questions report concordant or discordant key findings? (4) Are the administrative data reported by our institution to the SEER and the NCDB databases concordant with the data in our longitudinally maintained, physician-run orthopaedic oncology dataset?

METHODS

To answer our first three questions, PubMed was searched from 2001 through 2020 for all studies using the SEER or the NCDB databases to evaluate sarcoma. Studies were excluded from the review if they did not use these databases or studied anatomic locations other than the extremities, nonretroperitoneal pelvis, trunk, chest wall, or spine. To answer our first question, the number of SEER and NCDB studies were counted by year. The publication rate over the 20-year span was assessed with simple linear regression modeling. The difference in the mean number of studies between 5-year intervals (2001-2005, 2006-2010, 2011-2015, 2016-2020) was also assessed with Student t-tests. To answer our second question, we recorded and summarized descriptive data regarding author, journal, and content for these studies. To answer our third question, we grouped all studies by diagnosis, and then identified studies that shared the same diagnosis and a similar major study question with at least one other study. We then categorized study questions (and their associated studies) as having concordant findings, discordant findings, or mixed findings. Proportions of studies with concordant, discordant, or mixed findings were compared. To answer our fourth question, a coding audit was performed assessing the concordance of nationally reported administrative data from our institution with data from our longitudinally maintained, physician-run orthopaedic oncology dataset in a series of patients during the past 3 years. Our orthopaedic oncology dataset is maintained on a weekly basis by the senior author who manually records data directly from the medical record and sarcoma tumor board consensus notes; this dataset served as the gold standard for data comparison. We compared date of birth, surgery date, margin status, tumor size, clinical stage, and adjuvant treatment.

RESULTS

The number of musculoskeletal sarcoma studies using the SEER and the NCDB databases has steadily increased over time in a linear regression model (β = 2.51; p < 0.001). The mean number of studies per year more than tripled during 2016-2020 compared with 2011-2015 (39 versus 13 studies; mean difference 26 ± 11; p = 0.03). Of the 299 studies in total, 56% (168 of 299) have been published since 2018. Nineteen institutions published more than five studies, and the most studies from one institution was 13. Orthopaedic surgeons authored 35% (104 of 299) of studies, and medical oncology journals published 44% (130 of 299). Of the 94 studies (31% of total [94 of 299]) that shared a major study question with at least one other study, 35% (33 of 94) reported discordant key findings, 29% (27 of 94) reported mixed key findings, and 44% (41 of 94) reported concordant key findings. Both concordant and discordant groups included papers on prognostic factors, demographic factors, and treatment strategies. When we compared nationally reported administrative data from our institution with our orthopaedic oncology dataset, we found clinically important discrepancies in adjuvant treatment (19% [15 of 77]), tumor size (21% [16 of 77]), surgery date (23% [18 of 77]), surgical margins (38% [29 of 77]), and clinical stage (77% [59 of 77]).

CONCLUSION

Appropriate use of databases in musculoskeletal cancer research is essential to promote clear interpretation of findings, as almost two-thirds of studies we evaluated that asked similar study questions produced discordant or mixed key findings. Readers should be mindful of the differences in what each database seeks to convey because asking the same questions of different databases may result in different answers depending on what information each database captures. Likewise, differences in how studies determine which patients to include or exclude, how they handle missing data, and what they choose to emphasize may result in different messages getting drawn from large-database studies. Still, given the rarity and heterogeneity of sarcomas, these databases remain particularly useful in musculoskeletal cancer research for nationwide incidence estimations, risk factor/prognostic factor assessment, patient demographic and hospital-level variable assessment, patterns of care over time, and hypothesis generation for future prospective studies.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Trends in Overall Survival among Patients Treated for Sarcoma at a Large Tertiary Cancer Center between 1986 and 2014

Sarcomas are relatively rare malignancies accounting for about 1% of all cancer diagnoses. Studies on sarcomas comprising large cohorts covering extended time periods are lacking. Therefore, this study aimed to evaluate the impact of demographic, behavioral, and clinical characteristics on overall survival (OS) among individuals diagnosed with soft tissue sarcoma (STS) or bone sarcoma at the Moffitt Cancer Center between 1986 and 2014. Unadjusted and multivariable Cox proportional hazard regression (CPHR) models were constructed to generate hazard ratios (HRs) and 95% confidence intervals (CIs) to evaluate associations between a range of demographic, behavioral, and clinical characteristics, and OS. Additionally, Kaplan-Meier survival curves, associated log-rank statistics, and adjusted CPHR models were generated by time periods based on the year of first contact (1986-1994, 1995-1999, 2000-2005, 2006-2010, 2011-2014) to evaluate for temporal differences in OS. Of the 2570 patients, 2037 were diagnosed with STS, whereas 533 were diagnosed with bone sarcoma. At the time of analysis, 50% of the population were alive. In multivariable analyses, we observed poorer survival for patients ≥ 40 years of age (HR = 1.54, 95% CI = 1.34-1.78), current smokers (HR = 1.18, 95% CI = 1.01-1.37), patients with metastasis (HR = 2.19, 95% CI = 1.95-2.47), and patients not receiving first-line surgery treatment (HR = 2.11, 95% CI = 1.82-2.45). We discovered limited improvements in OS over time among individuals diagnosed with STS or bone sarcomas with the exception of gastrointestinal stromal tumors (GIST), which showed a significant improvement in OS across time periods (p = 0.0034). Overall, we identified well-established characteristics associated with OS (e.g., metastasis) in addition to factors (e.g., smoking status) not previously reported to impact OS. Improvements in survival over time have been relatively modest, suggesting the need for improved therapeutic options, especially for those diagnosed with less frequent sarcomas.

Extraskeletal Ewing sarcoma of the sciatic nerve

Extraskeletal Ewing sarcoma (EES) is a rare tumor diagnosed in children or young adults and is even more unusual in individuals over 30 years of age. Due to its rare occurrence and low index of suspicion, this tumor can pose diagnostic and therapeutic challenges. We present a case of a 60-year-old male with EES of the sciatic nerve, an unexpected entity given the patient's age, tumor type, and tumor location. This can mimic a nerve sheath tumor on imaging.

Sociodemographic Disparities in Presentation and Survival of Pediatric Bone Cancers

Osteosarcoma (OST) and Ewing sarcoma (ES) are the most common pediatric bone cancers. Patients with metastatic disease at diagnosis have poorer outcomes compared with localized disease. Using the Surveillance, Epidemiology, and End Results registries, we identified children and adolescents diagnosed with OST or ES between 2004 and 2015. We examined whether demographic and socioeconomic disparities were associated with a higher likelihood of metastatic disease at diagnosis and poor survival outcomes. In OST, Hispanic patients and those living in areas of high language isolation were more likely to have metastatic disease at diagnosis. Regardless of metastatic status, OST patients with public insurance had increased odds of death compared to those with private insurance. Living in counties with lower education levels increased odds of death for adolescents with metastatic disease. In ES, non-White adolescents had higher odds of death compared with white patients. Adolescents with metastatic ES living in higher poverty areas had increased odds of death compared with those living in less impoverished areas. Disparities in both diagnostic and survival outcomes based on race, ethnicity, and socioeconomic factors exist in pediatric bone cancers, potentially due to barriers to care and treatment inequities.

The Association between Race/Ethnicity and Cancer Stage at Diagnosis of Bone Malignancies: A Retrospective Cohort Study

INTRODUCTION AND OBJECTIVE

Limited data exists analyzing disparities in diagnosis regarding primary bone neoplasms (PBN). The objective of our study was to determine if there is an association between race/ethnicity and advanced stage of diagnosis of PBN.

METHODS

This population-based retrospective cohort study included patient demographic and health information extracted from the National Cancer Institute Surveillance, Epidemiology, and End Results Program (SEER). The main exposure variable was race/ethnicity categorized as non-Hispanic white (NH-W), non-Hispanic black (NH-B), non-Hispanic Asian Pacific Islander (NH-API), and Hispanic. The main outcome variable was advanced stage at diagnosis. Age, sex, tumor grade, type of bone cancer, decade, and geographic location were co-variates. Unadjusted and adjusted logistic regression analyses were conducted calculating odds ratios (OR) and corresponding 95% confidence intervals.

RESULTS

Race/ethnicity was not statistically significantly associated with advanced-stage disease. Adjusted OR for NH-B was 0.94 (95% CI: 0.78-1.38), for NH-API 1.07 (95% CI: 0.86-1.33) and for Hispanic 1.03 (95% CI: 0.85-1.25).

CONCLUSIONS

The lack of association between race and advanced stage of disease could be due to high availability and low cost for initial management of bone malignancies though plain radiographs. Future studies may include socioeconomic status and insurance coverage as covariates in the analysis.

Mitochondrial DNA haplogroup, genetic ancestry, and susceptibility to Ewing sarcoma

Based on current studies, the incidence of Ewing sarcoma (ES) varies significantly by race and ethnicity, with the disease being most common in patients of European ancestry. However, race/ethnicity has generally been self-reported rather than formally evaluated at a population level using DNA evidence. Additionally, mitochondrial dysfunction is a hallmark of ES, yet there have been no reported studies of mitochondrial genetics in ES. Thus, we evaluated both the mitochondrial and nuclear ancestries of 420 pediatric ES patients in the United States using whole-genome sequencing. We found that the mitochondrial DNA (mtDNA) genomes of only six (1.4 %) patients belonged to African L haplogroups, while those of 90 % of the patients belonged to macrohaplogroup R, which includes haplogroup H, the most common maternal lineage in Europe. Compared to the general US population, European haplogroups were significantly enriched in ES patients (p < 2.2e-16) and the African haplogroups are significantly impoverished (p < 4.6e-16). Using the ancestry informative markers defined in a National Genographic study, the vast majority of patients exhibited significant nuclear ancestry originating from the Mediterranean, Northern Europe, and Southwest Asia, including all six patients with African L mtDNAs. Very few had primarily African nuclear ancestry. This is the first genomic epidemiology study to simultaneously interrogate the mitochondrial and nuclear ancestries of ES patients. While supporting previous findings of enriched European ancestry in ES patients, these results also suggest alternative hypotheses for the significant contribution of mitochondrial ancestry in ES patients, as well as the protective role of African ancestry.

An international working group consensus report for the prioritization of molecular biomarkers for Ewing sarcoma

The advent of dose intensified interval compressed therapy has improved event-free survival for patients with localized Ewing sarcoma (EwS) to 78% at 5 years. However, nearly a quarter of patients with localized tumors and 60–80% of patients with metastatic tumors suffer relapse and die of disease. In addition, those who survive are often left with debilitating late effects. Clinical features aside from stage have proven inadequate to meaningfully classify patients for risk-stratified therapy. Therefore, there is a critical need to develop approaches to risk stratify patients with EwS based on molecular features. Over the past decade, new technology has enabled the study of multiple molecular biomarkers in EwS. Preliminary evidence requiring validation supports copy number changes, and loss of function mutations in tumor suppressor genes as biomarkers of outcome in EwS. Initial studies of circulating tumor DNA demonstrated that diagnostic ctDNA burden and ctDNA clearance during induction are also associated with outcome. In addition, fusion partner should be a pre-requisite for enrollment on EwS clinical trials, and the fusion type and structure require further study to determine prognostic impact. These emerging biomarkers represent a new horizon in our understanding of disease risk and will enable future efforts to develop risk-adapted treatment.

Resection with limb salvage in an Asian male adolescent with Ewing’s sarcoma: A case report

BACKGROUND

Ewing’s sarcoma is a highly malignant primary bone tumor that commonly affects children. For young patients, multidisciplinary treatment and limb salvage are recommended, and surgical plans considering the growth potential and bone activity after tumor resection are essential.

CASE SUMMARY

An 11-year-old Asian boy had a 1-mo history of a right-sided limping gait. Imaging revealed a proximal tumor with bone destruction and physeal involvement over the right femoral neck. He was diagnosed with stage IV (T1N0M1aG3) Ewing’s sarcoma with bilateral lung metastases. Neoadjuvant chemotherapy decreased the tumor size and confined it to the metaphyseal region. The patient underwent four stages of surgery: wide tumor excision plus reconstruction with vascular fibular bone graft plus internal fixation; repeat open reduction and internal fixation; femoral lengthening with orthosis after physeal maturity; and orthosis removal and bone elongation (approximately 6 cm). Following surgery, he could walk without discomfort and had almost equal-sized bilateral femoral heads, indicating physis preservation. The surgery was successful, and normal femoral head growth was achieved after complete remission. The patient was able to resume normal activities with equal length of the bilateral lower limbs.

CONCLUSION

Tumor treatment and reconstruction following resection are important in skeletally immature patients with Ewing’s sarcoma to improve quality of life.

Impact of racial disparities and insurance status in patients with bone sarcomas in the USA : a population-based cohort study

Aims

Socioeconomic and racial disparities have been recognized as impacting the care of patients with cancer, however there are a lack of data examining the impact of these disparities on patients with bone sarcoma. The purpose of this study was to examine socioeconomic and racial disparities that impact the oncological outcomes of patients with bone sarcoma.

Methods

We reviewed 4,739 patients diagnosed with primary bone sarcomas from the Surveillance, Epidemiology and End Results (SEER) registry between 2007 and 2015. We examined the impact of race and insurance status associated with the presence of metastatic disease at diagnosis, treatment outcome, and overall survival (OS).

Results

Patients with Medicaid (odds ratio (OR) 1.41; 95% confidence interval (CI) 1.15 to 1.72) and uninsured patients (OR 1.90; 95% CI 1.26 to 2.86) had higher risks of metastatic disease at diagnosis compared to patients with health insurance. Compared to White patients, Black (OR 0.63, 95% CI 0.47 to 0.85) and Asian/Pacific Islander (OR 0.65, 95% CI 0.46 to 0.91) were less likely to undergo surgery. In addition, Black patients were less likely to receive chemotherapy (OR 0.67, 95% CI 0.49 to 0.91) compared to White patients. In patients with chondrosarcoma, those with Medicaid had worse OS compared to patients with insurance (hazard ratio (HR) 1.65, 95% CI 1.06 to 2.56).

Conclusion

In patients with a bone sarcoma, the cancer stage at diagnosis varied based on insurance status, and racial disparities were identified in treatment. Further studies are needed to identify modifiable factors which can mitigate socioeconomic and racial disparities found in patients with bone sarcomas.

Cite this article: Bone Joint Res 2022;11(5):278–291.

Demographic and socioeconomic disparities in pediatric cancer in the United States: Current knowledge, deepening understanding, and expanding intervention

While survival of pediatric cancer has improved greatly over the past 40 years, demographic and socioeconomic disparities have meant that some groups have not benefitted as much from these advances. We conducted a rapid review to summarize literature on demographic and socioeconomic disparities in outcomes of childhood cancer, starting in 2000. We find that unequal outcomes have been noted for many of these groups across hematologic malignancies, central nervous system tumors, and other solid tumors, although occasional studies have noted absence of disparities for particular at-risk groups and diseases, and gaps in understanding of disparities for some cancer subtypes and groups still exist. These include disparities in duration of overall survival, risk of death, more extensive disease at presentation, and differences/delays in treatment. Black race, Hispanic ethnicity, lack of private insurance, and adolescent/young adult age are most often associated with these poorer outcomes. We then delve into documented and theorized causes of these disparities, including impaired access to care and clinical trials, differences in cancer biology, treatment non-adherence, language barriers, and implicit racial bias. Here, it is clear that socioeconomic factors account for a large proportion of disparities seen, although not all, and that the causes of disparities are complex and interconnected and still need to be better understood. Finally, in an effort to shift emphasis to addressing disparities, we review interventions against disparities that have been studied in childhood cancer patients and other populations, including improving clinical trial representation, communication, health literacy, and family navigation. We suggest ways forward in disparity mitigation toward a goal of achieving equitable cancer outcomes for all children.

An Efficient Nomogram to Predict Overall Survival of Patients with Pediatric Ewing's Sarcoma: A Population-Based Study

Background

The objective of our study was to develop and validate a nomogram to predict the overall survival (OS) of patients with pediatric Ewing’s sarcoma (PES).

Methods

Age, gender, race, tumor stage, tumor size, tumor site, treatment method, and survival time were collected from patients diagnosed with PES between 2004 and 2016 from the Surveillance, Epidemiology, and End Results (SEER) database. A total of 772 patients were randomly allocated to a training dataset (n = 579) and a validation dataset (n = 193). Then, univariate and multivariate analyses were performed to determine the prognostic effect of the selected variables. A nomogram was constructed to estimate the OS and it was further assessed using the concordance index (C-index), calibration curves, and receiver operating characteristic (ROC).

Results

Age, race, tumor size, and tumor stage were included in the nomogram. The C-index was 0.77 in the OS for the training dataset. The C-index for the validation dataset of the OS prediction was 0.75. Calibration plots and ROC curves showed excellent predictive accuracy.

Conclusion

Age, race, tumor stage, and tumor size were independent prognostic factors for patients with PES. The nomogram showed an accurate and reliable prognostic performance for PES patients.

Patterns of National Cancer Institute-Sponsored Clinical Trial Enrollment in Black Adolescents and Young Adults

BACKGROUND

Both adolescent and young adult (AYA) and Black or African American (hereafter referred to as Black) cancer patients are historically under-enrolled in cancer treatment trials (CTT). The purpose of this study was to quantify enrollment of Black AYAs in National Cancer Institute (NCI)-sponsored CTTs overall and by age, sex, and cancer diagnosis during 2000-2015.

METHODS

Utilizing data from NCI's Cancer Therapy Evaluation Program and the Surveillance, Epidemiology and End Results (SEER) Program, we assessed CTT enrollment in Black patients with cancer and measured changes in enrollment over time between the study periods 2000-2007 and 2008-2015. Enrollment patterns were compared across age groups (≤14 years [y], 15-19y, 20-29y, 30-39y and 40+ years), sex, and cancer diagnosis.

RESULTS

From 2000 through 2015, <3% of Black AYAs (20-39y) enrolled on CTTs. While AYAs had significantly higher cancer incidence than children, 20.5% fewer Black AYAs enrolled on CTTs. Enrollment was lowest among Black males 20-29y, with a mean of 18 enrolling in CTTs annually. The proportion of AYA enrollees who were Black did not change significantly over time periods (2000-2007 vs 2008-2015).

CONCLUSIONS

Few Black AYAs enroll in CTTs each year. Given known benefits of clinical trial participation and the well-documented racial and age-related differences in cancer outcomes, addressing barriers to enrollment in these patients may, in turn, reduce disparities. Targeted interventions aimed at increasing the CTT enrollment of Black cancer patients, particularly young Black men, are urgently needed.

PRECIS

This study documents that compared with Black children, Black adolescent, and young adult (AYA) patients were less likely to enroll in NCI-sponsored CTTs from 2000 to 2015. Black AYA male enrollment decreased with increasing age, highlighting disparities among this specific population in CTT enrollment.

Incidence Patterns and Outcomes of Ewing Sarcoma in South Korea (1999-2017): A Retrospective Analysis Using Korea Central Cancer Registry Data

Purpose

Due to low incidence, epidemiologic data of Ewing sarcoma in the Asian population are scarce. We aimed to examine the incidence pattern and outcome of patients with Ewing sarcoma in the Republic of Korea.

Materials and Methods

Data of patients with Ewing sarcoma diagnosed between 1999 and 2017 were obtained from the Korea Central Cancer Registry (KCCR). Incidence, clinical characteristics, and survival rates were analyzed and compared between different age groups.

Results

There were 788 cases (459 males, 329 females), with a median age at diagnosis of 20 years. The age-standardized rate of Ewing sarcoma was 1.01. The number of cases and incidence rates in each age group were as follows: children, 1.6; adolescents and young adults (AYA), 0.93; adults, 0.44; and elderly, 0.53. There were more male cases in children and the AYA group (p < 0.001). Extraskeletal tumors (p < 0.001), primary sites other than extremity (p=0.007), and presence of metastasis at diagnosis (p=0.031) were more frequent in the adults and elderly group. With a median survival time of 78 months, the 5-year overall survival (OS) rate of the entire cohort was 52%. Children fared best (5-year OS, 75%), and the 5-year OS of AYA patients (51%) approximated the OS of the entire cohort. A two-fold difference of 5-year OS was observed between adults and elderly patients (42% vs. 19%). On univariate and multivariate analyses, age ≥ 15 years and presence of metastasis were adverse prognostic factors.

Conclusion

This was the first epidemiologic study of Ewing sarcoma using the KCCR data. With a similar incidence to other Asian countries, the survival rate was slightly lower than that of Euro-American cases. Collaborative clinical studies are necessary to improve the outcome of Ewing sarcoma in low-incidence populations.

Modeling fusion gene-associated sarcoma: Advantages for understanding sarcoma biology and pathology

Disease-specific gene fusions are reportedly major driver mutations in approximately 30% of bone and soft tissue sarcomas. Most fusion genes encode transcription factors or co-factors that regulate downstream target genes, altering cell growth, lineage commitment, and differentiation. Given the limitations of investigating their functions in vitro, the generation of mouse models expressing fusion genes in the appropriate cellular lineages is pivotal. Therefore, we generated a series of mouse models by introducing fusion genes into embryonic mesenchymal progenitors. This review describes mouse models of Ewing, synovial, alveolar soft part, and CIC-rearranged sarcomas. Furthermore, we describe the similarities between these models and their human counterparts. These models provide remarkable advantages to identify cells-of-origin, specific collaborators of fusion genes, angiogenesis key factors, or diagnostic biomarkers. Finally, we discuss the relationship between fusion proteins and the epigenetic background as well as the possible role of the super-enhancers.

Comparative international incidence of Ewing sarcoma 1988 to 2012

Ewing sarcoma (ES) is the second most common primary bone tumor in children and adolescents. There are few known epidemiological or genetic risk factors for ES. Numerous reports describe incidence rates and trends within the United States, but international comparisons are sparse. We used the Cancer Incidence in Five Continents (CI5) data to estimate age standardized incidence rates (ASRs; cases per million) and 95% confidence intervals (95% CIs), male-to-female incidence rate ratios (IRRs; 95% CI), and the average annual percent change in incidence (AAPC; 95% CI) for ES by geographic region for children and adults aged 0 to 49 years. We also estimated the ASR for each country or country subpopulation among the 10- to 19-year-old age range; capturing the peak incidence of ES. In total, 15 874 ES cases ages 0 to 49 were reported in the CI5 series between 1988 and 2012. AAPC estimates varied by age group and geographic region. Most of the statistically significant AAPCs showed an increased incidence over time; the only statistically significant decreases in incidence were observed among 20- to 29-year-olds and 30- to 39-year-olds in Southern Asia at -1.93% and -1.67%. When categorized by predominant ancestry, we observed countries and subpopulations with predominately African, East Asian, and Southeast Asian ancestry had the lowest incidence rates, whereas Pacific Islanders and populations with predominantly European and North African/Middle Eastern ancestry had the highest. An excess incidence in males was observed in most regions. Our results highlight substantial variation in ES incidence across geographic populations, reflecting potential ancestral influence on disease risk.

Epiphyseal Ewing Sarcoma in a skeletally mature patient: A case report and review of the literature

While Ewing sarcoma of bone is the second most common primary osseous malignancy in childhood where it typically involves the diaphysis or metadiaphyses of long bones of skeletally immature patients, primary epiphyseal involvement of the long bone in skeletally mature patients is rare with no cases reported in the literature to our knowledge, rendering this case the first of its kind.

We present the first case of primary Ewing Sarcoma of the epiphyses of the long bones in a skeletally mature 20-year-old male patient. The patient initially presented with left knee stiffness and pain that was empirically treated with non-steroidal anti-inflammatory medications. His pain progressed despite treatment. An x-ray of the left knee was obtained 5 months later demonstrating an irregular lucent lesion in the medial femoral condyle. A subsequent MRI revealed an enhancing lesion in the medial femoral condyle, and when biopsied it was consistent with Ewing sarcoma (positive for EWSR1gene rearrangement by fluorescence in situ hybridization). The lesion was resected surgically, and the patient underwent neoadjuvant chemotherapy with a good clinical outcome.

Risikofaktoren für Krebserkrankungen im Kindes- und Jugendalter

Die Ursachen von Krebs im Kindes- und Jugendalter sind weitestgehend unbekannt. Beispiele für konsistent beobachtete Risikofaktoren, die in umfangreichen epidemiologischen Untersuchungen identifiziert wurden, sind Strahlenexposition, Chemotherapie, niedriges und hohes Geburtsgewicht, höheres Alter der Mutter, Geschlecht und das Vorhandensein angeborener Anomalien. Diese Faktoren erklären jedoch nur einen geringen Anteil aller inzidenten Fälle. Die derzeit vielversprechendsten Ansätze zur Verbesserung des Verständnisses über die Ursachen von Krebserkrankungen im Kindes- und Jugendalter stammen von genetischen Analysen. Abgesehen von den durch genomweite Assoziationsstudien identifizierten Allelen mit geringem Krebsrisiko wurde festgestellt, dass seltene Keimbahnvarianten, die Krebsprädispositionsyndrome verursachen, mit einem erhöhten Risiko für die Entwicklung von Krebs im Kindes- und Jugendalter verbunden sind. Dieser Beitrag fasst das aktuelle Wissen über die exogenen und endogenen Ursachen von Krebserkrankungen in den frühen Lebensjahren zusammen und gibt einen Ausblick darauf, wie stetig wachsendes Wissen in diesem Bereich zukünftige präventive, diagnostische und therapeutische Strategien beeinflussen könnte.

Insurance impacts survival for children, adolescents, and young adults with bone and soft tissue sarcomas

Background

While racial/ethnic survival disparities have been described in pediatric oncology, the impact of income has not been extensively explored. We analyzed how public insurance influences 5‐year overall survival (OS) in young patients with sarcomas.

Methods

The University of California San Francisco Cancer Registry was used to identify patients aged 0‐39 diagnosed with bone or soft tissue sarcomas between 2000 and 2015. Low‐income patients were defined as those with no insurance or Medicaid, a means‐tested form of public insurance. Survival curves were computed using the Kaplan‐Meier method and compared using log‐rank tests and Cox models. Causal mediation was used to assess whether the association between public insurance and mortality is mediated by metastatic disease.

Results

Of 1106 patients, 39% patients were classified as low‐income. Low‐income patients were more likely to be racial/ethnic minorities and to present with metastatic disease (OR 1.96, 95% CI 1.35‐2.86). Low‐income patients had significantly worse OS (61% vs 71%). Age at diagnosis and extent of disease at diagnosis were also independent predictors of OS. When stratified by extent of disease, low‐income patients consistently had significantly worse OS (localized: 78% vs 84%, regional: 64% vs 73%, metastatic: 23% vs 30%, respectively). Mediation analysis indicated that metastatic disease at diagnosis mediated 15% of the effect of public insurance on OS.

Conclusions

Low‐income patients with bone and soft tissue sarcomas had decreased OS regardless of disease stage at presentation. The mechanism by which insurance status impacts survival requires additional investigation, but may be through reduced access to care.

Characteristics and prognosis of pelvic Ewing sarcoma: a SEER population-based study

Background

The pelvis is one of the primary sites of Ewing sarcoma (ES) and is associated with poorer prognoses than the extremities. Due to the rarity of this disease and limited data available, the prognostic factors of pelvic ES remain controversial. Thus, this study aimed to identify independent prognostic factors, and develop a nomogram for predicting survival rates in patients with pelvic ES.

Methods

Using data provided by the Surveillance, Epidemiology, and End Results (SEER) database, variables including age, sex, race, tumor size, tumor stage, surgery, and radiotherapy were analyzed using the Kaplan–Meier method and Cox proportional hazards regression. Based on the results of multivariate analyses, a nomogram was built to predict the overall survival (OS) of patients with pelvic ES. The performance of the nomogram was evaluated by the concordance index (C-index).

Results

A total of 267 cases diagnosed between 2004 and 2016 were included in the study. Univariate and multivariate analyses showed that patients who were younger, white, had a localized tumor stage, or underwent surgery were associated with improved prognoses, while no significant differences were observed in OS based on sex, tumor size, or radiotherapy. A nomogram was developed and the C-index was 0.728, indicating adequate performance for survival prediction.

Conclusions

Age, race, tumor stage, and surgery were identified as independent prognostic factors for the OS of pelvic ES. The nomogram developed in this study can individually predict 3- and 5-year OS in patients with pelvic ES.

Ewing Sarcoma in Nepal Treated With Combined Chemotherapy and Definitive Radiotherapy

PURPOSE

To our knowledge, we conducted the first prospective oncologic clinical trial in Nepal aimed at providing state-of-the-art chemotherapy to patients with Ewing sarcoma. The efficacy of external-beam radiotherapy (RT) as the sole local treatment modality was explored and deemed justified as a result of the lack of available advanced tumor-orthopedic services in Nepal.

PATIENTS AND METHODS

Twenty patients, 11 female and 9 male patients between the ages of 6 and 37 years, with newly diagnosed Ewing sarcoma were enrolled. Neoadjuvant combination chemotherapy, comprising well-established drug combinations, was administered in five courses before external-beam RT, during which one course of etoposide and ifosfamide was given. After RT, six additional chemotherapy courses were scheduled.

RESULTS

RT was tolerated well, providing rapid symptom relief and local tumor control, with no pathologic fractures observed among the 15 patients who received such treatment. Eleven patients completed the entire treatment protocol; seven patients were under continued follow-up, with no evidence of disease in six patients at a median follow-up time of 2.3 years (range, 1.3 to 3.1 years) and one patient alive but with a regional recurrence. Four patients experienced metastatic relapse and died as a result of their disease. Three treatment-related deaths linked to toxicity from chemotherapy occurred. Four of the six patients who refused to complete the treatment protocol and were lost to follow-up experienced progressive disease and were assumed dead.

CONCLUSION

This study was feasible with RT as the sole local treatment modality in combination with chemotherapy. As a result of the high number of patients lost to follow-up, no firm conclusions can be drawn, but the majority of the patients who completed treatment obtained durable long-term remissions.

Analysis of bone and soft-tissue sarcomas registered during the year 2012 at Tata Memorial Hospital, Mumbai, with clinical outcomes

Introduction

Primary bone and soft tissue sarcomas are rare, but diagnostically and therapeutically challenging group of tumors, requiring multidisciplinary management. There are limited documented studies from multidisciplinary teams , in the form of comprehensive analysis of these tumors, from our country. This study is an analysis of cases of osteosarcomas, Ewing sarcomas (ESs), chondrosarcomas (CSs), and soft-tissue sarcomas (STSs), registered at our institution during 2012.

Methods

Clinical details, including outcomes of cases of bone and STSs, during the year 2012, were retrieved from the medical records of our institution and were further analyzed.

Results

Ninety-five high-grade, extremity-based, treatment-naïve cases of osteosarcomas were treated with a novel, dose-dense, nonhigh-dose methotrexate-based OGS-12 protocol. Good histopathologic response (necrosis ≥90%) was achieved in 59% nonmetastatic and 56% metastatic patients. At a median follow-up of 48 months, the estimated 5-year event-free survival and overall survival (OS) were 67% and 78%, respectively. In the metastatic cohort at a median follow-up of 51 months, the 5-year estimated progression-free survival was 24% and OS was 26%. Among 87 (73.2%) nonmetastatic and 32 (26.8%) metastatic, analyzable cases of ES, at a median follow-up of 40 months, the disease-free survival (DFS) and OS in the nonmetastatic group were 62% and 83%; in the metastatic group, they were 37.5% and 65.6%, respectively. Among 40 cases of CSs (33 nonmetastatic and 7 metastatic), 21 had limb salvage surgery while 5 had amputation. Microscopically, 90.4% were Grade II CSs. Five-year OS and DFS were 84.6% and 71%, respectively. Among 189 high-grade, extremity-based STSs (89% nonmetastatic), synovial sarcoma was the most common subtype (31%). Eighty-five percent had limb preservation surgery; a majority were offered adjuvant radiation with or without chemotherapy. At a median follow-up of 51 (1-63) months, 3-year local control, DFS, and OS were 81%, 48%, and 64%, respectively.

Conclusions

The novel OGS 12 and Ewing Family of Tumors 2001 protocols have shown comparable outcomes to international standards in cases of osteosarcoma and ES, respectively, and merit wider applications, especially in low- and middle-income countries (LMICs). Outcomes in STS and CSs were also comparable and underscore the importance of a multidisciplinary approach for the management of sarcomas in LMICS.

Descriptive epidemiology and outcomes of bone sarcomas in adolescent and young adult patients in Japan

BACKGROUND

There have been fewer improvements in the clinical outcomes of adolescent and young adult (AYA) patients with cancer than for children and older adults, possibly because fewer studies focus on patients in this age group. The aims of this study were (1) to determine survival rates of bone sarcoma among AYAs in Japan (for comparison with other age groups), and (2) to establish whether belonging to the AYA age group at diagnosis was correlated with poor cancer survival in Japan.

METHODS

A total of 3457 patients diagnosed with bone sarcoma (1930 male and 1527 female) were identified from 63,931 records in the Bone and Soft Tissue Tumor (BSTT) registry, a nationwide Japanese database, from 2006 to 2013. The histologic subtypes of bone sarcoma were osteosarcoma, chondrosarcoma, and Ewing sarcoma. The primary endpoints for prognosis were the occurrence of tumor-related death. We compared the epidemiological features of AYAs with other age groups. The cancer survival rates were calculated using the Kaplan-Meier method. Cox proportional hazards models were used to analyze the prognostic factors for cancer survival.

RESULTS

The majority of AYA had osteosarcoma 631 (56.2%), while 198 (17.6%) had chondrosarcoma. The frequency of bone sarcoma occurrence was highest among AYA patients, who accounted for a marked proportion of patients with each type of sarcoma. With the exception of sarcoma type, AYA patients did not significantly differ from patients in other age groups for any of the investigated clinicopathological parameters. Cancer survival of AYA patients was significantly higher than in the elderly. Univariate and multivariate analyses revealed that AYA status was not a predictor of poor cancer survival. However, older age (≥65 years) was a predictor of poor cancer survival in patients with overall bone sarcoma, osteosarcoma, chondrosarcoma.

CONCLUSION

This epidemiological study is the first to investigate AYA patients with bone sarcoma using the nationwide BSTT Registry. We found that cancer survival of AYA patients was significantly higher than that of the elderly. AYA status was not a predictor of poor cancer survival in Japan.

The impact of racial/ethnic disparities on survival for children and young adults with chest wall sarcoma: A population-based study

BACKGROUND

To determine whether there are racial/ethnic disparities in disease presentation, treatment and survival outcomes among children and young adults with chest wall sarcomas.

METHODS

The Surveillance, Epidemiology and End Results (SEER) database was analyzed for patients 21 years old and younger with chest wall sarcoma. We performed multivariate logistic regression to investigate the association of race/ethnicity with advanced stage of disease at presentation and likelihood of undergoing surgical resection. Overall survival (OS) was evaluated using Cox regression modeling to calculate hazard ratios with 95% confidence intervals.

RESULTS

A total of 669 patients were identified: 393 non-Hispanic whites (NHW) (59%), 151 Hispanics (23%), 64 non-Hispanic blacks (NHB) (11%), and 64 other race/ethnicity (9%). The 5- and 10-year OS rates for the entire cohort were 69% and 64%, respectively. NHB had significantly worse 5-year and 10-year OS compared to NHW based on the log rank test (61% versus 70%, 52% versus 66%, respectively; p = 0.037).). Most patients (80%) underwent surgical resection. However, NHB were less likely than NHW to undergo surgical resection by multivariate analysis (OR 0.43, 95% CI 0.22-0.82).

CONCLUSIONS

NHB children and young adults with chest wall sarcoma have decreased overall survival. In addition, NHB are less likely to undergo surgical resection which may contribute to survival disparities. It is paramount that health care providers work to close the treatment gap between racial/ethnic groups to improve survival in children and young adults with chest wall sarcoma.

LEVEL OF EVIDENCE

Level III Treatment Study.

Trends in incidence of Ewing sarcoma of bone in India - Evidence from the National Cancer Registry Programme (1982-2011)

Background

Ewing sarcoma is a malignant tumour found mainly in childhood and adolescence. The present study aims at analyzing the data on Ewing sarcoma cases of bone from the National Cancer Registry Programme, India to provide incidence, patterns, and trends in the Indian population.

Materials and Methods

The data of five Population Based Cancer Registries (PBCR) of Bangalore, Mumbai, Chennai, Bhopal and Delhi over 30 years period (1982- 2011) were used to calculate the Age Specific and Age Standardized Incidence Rates (ASpR and ASIR), and trends in incidence was analyzed by linear and Joinpoint Regression.

Results

Ewing sarcoma comprised around 15 % of all bone malignancies. Sixty-eight percent were 0-19 years, with 1.6 times risk of tumour in bones of limbs as compared to other bones. The highest incidence rate (per million) was in the 10-14 years age group (male -4.4, female -2.9) with significantly increasing trend in ASpR observed in both sexes. Pooled ASIR per million for all ages was higher in male (1.6) than female (1.0) with an increasing rate ratio of ASIR with increase in age. Trend of pooled ASIR for all ages was significantly increased in both sexes. Twelve percent cases were reported in ≥30 years of age.

Conclusion

This paper has described population based measurements on burden and trends in incidence of skeletal Ewing in India. These may steer further research questions on the clinical and molecular epidemiology to explain factors associated with the increasing incidence of Ewing sarcoma bone observed in India.

Evaluation of racial disparities in pediatric optic pathway glioma incidence: Results from the Surveillance, Epidemiology, and End Results Program, 2000-2014

BACKGROUND

Racial predilection to pediatric cancer exists; however optic pathway glioma (OPG) risk differences by race/ethnicity are undefined. We estimated differences in OPG incidence across racial/ethnic groups in a multi-state cancer surveillance registry in the United States.

METHODS

OPG data were obtained from the Surveillance, Epidemiology, and End Results (SEER-18) Program, 2000-2014. Race/ethnicity was categorized as: White; Black; Asian; Other; and Latino/a ("Spanish-Hispanic-Latino"). Latino/a included all races, while all other categories excluded those identified as Latino/a. Age-adjusted incidence rates and rate ratios (IRR) with 95% confidence intervals (CIs) were generated in SEER-STAT (v8.3.4).

RESULTS

Data on 709 OPG cases ages 0-19 were abstracted from SEER-18. Minority children experienced lower age-adjusted OPG incidence rates compared to White children (IRR_Black = 0.38, 95% CI: 0.28-0.50; IRR_Asian = 0.41, 95% CI: 0.29-0.58; and IRR_Latino/a = 0.39, 95% CI: 0.32-0.48). In subgroup analyses among the highest risk age categories (0-4, 5-9), minority children experienced lower incidence rates compared to White children. Specific patterns for Latinos/as also emerged. Latino/a children ages 0-4 experienced the lowest incidence rates of all racial/ethnic groups compared to Whites (0.24 per 100,000 person-years versus 0.66 per 100,000 person-years, respectively), whereas among those ages 5-9, Black and Asian children experienced the lowest incidence rates (0.08 per 100,000 person-years each).

CONCLUSIONS

Incidence of OPGs was highest among White children. This study represents one of the largest to assess differences in OPG susceptibility by race/ethnicity. These findings may inform future studies that seek to evaluate modifying factors for this pediatric tumor including tumorigenesis, treatment, outcome, and long-term late effects.

An overview of disparities in childhood cancer: Report on the Inaugural Symposium on Childhood Cancer Health Disparities, Houston, Texas, 2016

The Inaugural Symposium on Childhood Cancer Health Disparities was held in Houston, Texas, on November 2, 2016. The symposium was attended by 109 scientists and clinicians from diverse disciplinary backgrounds with interests in pediatric cancer disparities and focused on reviewing our current knowledge of disparities in cancer risk and outcomes for select childhood cancers. Following a full day of topical sessions, everyone participated in a brainstorming session to develop a working strategy for the continued expansion of research in this area. This meeting was designed to serve as a springboard for examination of childhood cancer disparities from a more unified and systematic approach and to enhance awareness of this area of need.

Loss of MTAP expression is a negative prognostic marker in Ewing sarcoma family of tumors

Aim: The Ewing sarcoma family of tumors (ESFT) is a group of malignant small round cell neoplasms of bones and soft tissues closely histogenetically related. Methylthioadenosine phosphorylase (MTAP) deficiency has been recently associated with increased tumor aggressiveness and poor outcomes in different types of neoplasms. However, the expression of this biomarker and its biological role in ESFT remain largely unknown. Methods: Immunohistochemical expression of MTAP was accessed in 112 patients with ESFT in a tissue microarray platform and associated with clinicopathological parameters and overall survival (OS). Results: Loss of MTAP expression was significantly associated with lower OS in both univariate and multivariate analyses. Conclusion: Loss of MTAP expression is an independent negative prognostic biomarker in ESFT.

Pediatric head and neck bone sarcomas: An analysis of 204 cases

OBJECTIVES

To analyze the demographics, survival, and treatment efficacy of pediatric sarcomas of the facial skeleton and skull.

METHODS

Retrospective study of cases from the US National Cancer Institute's Surveillance, Epidemiology, and End Results database. Pediatric patients between the ages of 0 and 18 diagnosed with a malignant sarcoma of either the mandible or the bones of skull, face, and associated joints from 1973 to 2013 were studied.

RESULTS

In total, 204 patients were included in the analysis. The average age at diagnosis was 11.39 (±5.15) years with a male-to-female ratio of 1.4:1. Whites were the most commonly affected race (76.0%). Malignant mandible sarcomas accounted for 29.9% of the cohort (n = 61). The most common pathology was osteosarcoma, which accounted for 43.6% of the cohort (n = 89). Among patients with known histologic grade (n = 95), 26.0% were AJCC stage III or IV. Overall, 5-year disease-specific survival (DSS) was 80.6%. When stratified by treatment modality, 5-year DSS was 86.0% for surgery alone, 67.9% for radiation alone, and 75.3% for surgery with adjuvant radiotherapy (p = 0.041).

CONCLUSIONS

Osteosarcoma, Ewing's sarcoma, and chondrosarcoma are the most common subtypes of pediatric head and neck bone sarcoma. Such sarcomas more commonly affect whites and males during pubertal ages. Disease-specific survival is not affected by primary site. Surgery alone is the mainstay of treatment, and demonstrates higher 5-year disease-specific survival compared to radiotherapy alone. Adjuvant radiotherapy does not seem to increase survival, but further investigation is warranted.

Infection-related mortality in Hispanic and non-Hispanic children with cancer

BACKGROUND

Hispanic children with cancer experience poorer survival than their White counterparts. Infection is a known cause of cancer-related mortality; however, little is known about the risk of infection-related death among Hispanic children with cancer. We examine the association of Hispanic ethnicity with infection-related mortality and life-threatening events among children with cancer.

PROCEDURE

For a cohort of all pediatric cancer patients diagnosed from 1986 to 2012 and treated at a single tertiary care center, we obtained national death records to determine all-cause mortality and infection-related mortality, as well as intensive care unit (ICU) admissions as a surrogate for life-threatening events. Cox proportional hazard models assessed all-cause mortality and infection-related mortality using ethnicity as the main independent variable. ICU admission rates were modeled using a zero-inflated Poisson regression model. Models were adjusted for gender, diagnosis year, age, residential location, and diagnosis.

RESULTS

Of 6,198 patients, 741 (12%) were Hispanic. Mean follow-up was 11 years (SD = 8.04). There were 1,205 deaths, with 193 attributable to infection. Differences in all-cause mortality between Hispanic and non-Hispanic patients did not reach significance (hazard ratio [HR] = 1.14, 95% confidence interval [CI]: 0.96-1.36). However, Hispanic patients were 68% (HR = 1.68, 95% CI: 1.16-2.43) more likely to have an infection-related cause of death. Hispanic ethnicity was statistically associated with a higher rate of ICU admissions (rate ratio = 1.32, 95% CI: 1.12-1.56).

CONCLUSION

Hispanic pediatric cancer patients were more likely to have an infection-related death and higher rates of ICU admissions than non-Hispanic patients. Infection may be an overlooked contributor to poorer outcomes among Hispanic patients.

Overview of extremity musculoskeletal neoplasms at the Ahmadu Bello University Teaching Hospital Zaria, Nigeria

Background:

The burden of managing patients with musculoskeletal neoplasms in the West African sub-region is quite significant. This is largely due to late presentation, delay in making diagnosis, and failure of obtaining consent to certain surgical procedures. Improvements in diagnosis and treatment over the years have however increased life and limb survival for many patients. This study was aimed at evaluating the clinicopathologic pattern of neoplasm as it affects the upper and lower limbs with a view to determining the most common types, the most involved sites of the body and the age at presentation of these tumors.

Materials and Methods:

A total of 65 patients with histologically confirmed neoplasm of the upper and lower limbs arising from bone, cartilage, skeletal muscle, synovium, and tendon sheath were retrospectively selected 7 years from January 2008 to 2015.

Results:

Forty-one (63.1%) patients were males, whereas 24 (36.9%) were females. Age range is between 5 and 75 years, average of 30.8 years. Lower limb involvement was recorded in 40 (61.5%) patients, with remaining 25 (38.5%) patients in upper limbs. 28 (43.1%) patients had benign lesion, whereas 37 (56.9%) were malignant. Giant cell tumor (GCT) was the most frequent benign tumor (50%) while osteogenic sarcomas top the list on the malignant variety (32.4%). The most commonly affected bones were tibia, carpal-metacarpal, and femur in that order.

Conclusion:

In our center, GCT and osteogenic sarcoma are the most frequently encountered benign and malignant musculoskeletal extremity neoplasms, respectively, with the tibial bone being most commonly affected.

Death Within 1 Month of Diagnosis in Childhood Cancer: An Analysis of Risk Factors and Scope of the Problem

Purpose Despite advances in childhood cancer care, some patients die soon after diagnosis. This population is not well described and may be under-reported. Better understanding of risk factors for early death and scope of the problem could lead to prevention of these occurrences and thus better survival rates in childhood cancer. Methods We retrieved data from SEER 13 registries on 36,337 patients age 0 to 19 years diagnosed with cancer between 1992 and 2011. Early death was defined as death within 1 month of diagnosis. Socioeconomic status data for each individual's county of residence were derived from Census 2000. Crude and adjusted odds ratios and corresponding 95% CIs were estimated for the association between early death and demographic, clinical, and socioeconomic factors. Results Percentage of early death in the period was 1.5% (n = 555). Children with acute myeloid leukemia, infant acute lymphoblastic leukemia, hepatoblastoma, and malignant brain tumors had the highest risk of early death. On multivariable analysis, an age younger than 1 year was a strong predictor of early death in all disease groups examined. Black race and Hispanic ethnicity were both risk factors for early death in multiple disease groups. Residence in counties with lower than median average income was associated with a higher risk of early death in hematologic malignancies. Percentages of early death decreased significantly over time, especially in hematologic malignancies. Conclusion Risk factors for early death in childhood cancer include an age younger than 1 year, specific diagnoses, minority race and ethnicity, and disadvantaged socioeconomic status. The population-based disease-specific percentages of early death were uniformly higher than those reported in cooperative clinical trials, suggesting that early death is under-reported in the medical literature. Initiatives to identify those at risk and develop preventive interventions should be prioritized.

Epidemiology and Etiology of Sarcomas

Sarcomas are rare malignancies of mesenchymal origin and are broadly divided into soft tissue sarcomas and bone sarcomas. The etiology of these tumors is largely unknown, and most sarcomas are sporadic. A small subset of sarcomas is associated with certain genetic syndromes and environmental factors. Ionizing radiation is the strongest environmental factor linked to sarcoma development.

Pediatric soft tissue tumor pathology: A happy morpho-molecular union

Since its foundation by remarkably talented and insightful individuals, prominently including Pepper Dehner, pediatric soft tissue tumor pathology has developed at an immense rate. The morphologic classification of tumoral entities has extensively been corroborated, but has also evolved with refinement or realignment of these classifications, through accruing molecular data, with many derivative ancillary diagnostic assays now already well-established. Tumors of unclear histogenesis, classically morphologically undifferentiated, are prominent amongst pediatric sarcomas, however, the classes of undifferentiated round- or spindle-cell-tumors-not-otherwise-specified are being dismantled gradually with the identification of their molecular underpinnings. Within recent years, for example, numerous subcategories of 'Ewing-like' round cell sarcoma have emerged. Such advances have provided the basis for novel diagnostic and prognostic sub-classifications. Efforts at defining cell- or lineage-of-origin for several tumor types have produced interesting insights especially for rhabdomyosarcoma. The remarkably early onset of pediatric sarcomas defies the theory necessitating stochastic accumulation of several somatic mutations for cancer development and indeed, these tumors may be remarkably genomically stable, often belying their aggressive nature. Much is coming to light recently regarding the role of epigenetic modifications in the evolution of these sarcomas. Indeed the morphologic features of embryonal tumors generally (not just sarcomas) may be highly reminiscent of arrested differentiation, and given the tight epigenetic regulation of cell fate determination and cell identity maintenance, a theory of epigenetically-driven oncogenesis sits easily with these tumors. The age-delimited distinct biologies of 'pediatric' and adult GIST are intriguing, particularly, the SDH-deficient 'pediatric' form, driven by a metabolic defect, but resulting in epigenetic dysregulation with genome-wide DNA methylation changes. There is little doubt that many of the gaps in our understanding of pediatric sarcoma biology will be filled by a deeper appreciation of the role of dysregulated epigenetics including chromatin biology, perhaps best exemplified in malignant rhabdoid tumor. The field of pediatric soft tissue tumor pathology grows ever more interesting. Importantly though, it must be emphasized, that none of this progress could have occurred, or indeed continue, without the initial step of accurate diagnosis, founded solidly on morphology - thank you Pepper for your unparalleled contributions to this field! The opportunity to be your apprentice for five years has been a bigger and more positive influence than words can express.

Pediatric Malignant Bone Tumors: A Review and Update on Current Challenges, and Emerging Drug Targets

Osteosarcoma (OS) and the Ewing sarcoma family of tumors (ESFT) are the most common malignant bone tumors in children and adolescents. While significant improvements in survival have been seen in other pediatric malignancies the treatment and prognosis for pediatric bone tumors has remained unchanged for the past 3 decades. This review and update of pediatric malignant bone tumors will provide a general overview of osteosarcoma and the Ewing sarcoma family of tumors, discuss bone tumor genomics, current challenges, and emerging drug targets.

Conditional Survival and Predictors of Late Death in Patients With Ewing Sarcoma

PURPOSE

Long-term survivors of Ewing sarcoma (EWS) are at considerable risk for future complications, including late relapse and death. Data on prognostic factors for late death in those who have survived beyond 5 years are lacking.

METHODS

We conducted a retrospective cohort study using the Surveillance, Epidemiology, and End Results database. We obtained clinical features and outcome data on 1,351 patients with EWS who had survived 60 months or more. From these data, we performed univariate and multivariable analyses of overall survival (OS) using log-rank tests and Cox proportional hazard models.

RESULTS

Of 1,351 patients in the cohort, there were 209 deaths, 144 (69%) of which were reported to be due to EWS. The OS for 5-year survivors at 10 years was 87.5% (95% confidence interval 85.4-89.3%). Univariate adverse prognostic factors for late death in 5-year survivors included age ≥ 18 years at initial diagnosis, male sex, and axial/pelvic primary site. Initial stage was not prognostic. Independent adverse prognostic factors for late death included black race (hazard ratio [HR] 2.16, P = 0.01), age ≥ 18 years at diagnosis (HR 2.02, P < 0.001), male sex (HR 1.43, P = 0.01), and axial/pelvic primary site (HR 1.43, P = 0.02).

CONCLUSIONS

The majority of late deaths in 5-year survivors are due to EWS. Black race, age ≥18 at diagnosis, male sex, and axial/pelvic primary site (but not stage at diagnosis) are independently associated with increased risk of late death.