Epidemiology of bone tumors in children and adolescents: a retrospective study of 266 patients in the south of Tunisia.

Although bone tumors (BT) are relatively uncommon among the human neoplasm, they constitute the most frequent tumors in children and adolescents (CAA). Little information is available about the epidemiologic features of BT in CAA. We aimed to present and discuss epidemiological characteristics of BT in CAA in southern Tunisia, regarding the different histological types. This is a retrospective study including cases of BT in CAA collected in the pathology department at the Habib Bourguiba university hospital over a period of 15 years (2006- 2020). A total of 266 BT was diagnosed in our institution (42,7% among all BT in Southern Tunisia) divided into 200 benign bone tumors (BBT) (75,2%) and 66 malignant bone tumors (MBT) (24,8%). The mean age for all BT was 14,2 years (3-20 years) with male predominance (sex ratio: 1,48). The most common tumor was osteochondroma (42.2%) followed by osteosarcoma (14.6%) and Ewing sarcoma (6.4%). For BBT, the most affected age group was the 16 to 20 year - old - group (50,7%) with a male predominance (59.8%) and a predilection for lower limb (66.8%) then the upper limb (16,8%). Osteochondroma was the most common histological type (56.5%) followed by aneuvrysmal cyst (8,5%) and osteoid osteoma (6,5%). For MBT, the mean age was 12,5 years (5-20 years) and the most affected age group was the 11 to 15 year -old -group (59%). Boys were more affected (60.6%), with a preference for the lower limb (57%) followed by the pelvis (15,6%). Osteosarcoma was the most common MBT (60%) followed by Ewing sarcoma (24%). Given their rarity and heterogeneity, the diagnosis of BT is particular in CAA and requires a multidisciplinary approach. The reporting of epidemiological studies remains essential in order to expand our knowledge regarding these uncommon tumors.

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.

Ewing's sarcoma in adolescents and adults - 10-year experience from a tertiary cancer center in India.

BACKGROUND: Ewing's sarcoma (EWS) is an aggressive small round cell tumor, affecting bone and soft tissues and is mostly seen in childhood and second decade of life. EWS accounts for 10-12% of bone tumors in more than 15 years age group and is even rarer after 40 years of age. MATERIALS AND METHODS: This retrospective analysis was conducted among patients aged more than 15 years with histologically proven EWS. RESULTS: Among 240 cases of EWS treated at our center during 2001-2010, 130 (54%) were more than 15 years of age. The median age was 20 years with a male: female ratio of 2.4:1. Ninety percent had skeletal EWS, 10% had extra skeletal EWS, and 37% patients were metastatic at presentation. Eighty-two received curative treatment with chemotherapy (vincristine, doxorubicin, cyclophosphamide, ifosfamide, etoposide (VAC/IE)) along with local treatment, radiotherapy (RT) in 61, surgery alone in seven, and RT plus surgery in 14. Two- and 5-year overall survival (OS) was 43.3% and 25.5%, respectively, for the entire series. The OS for the non-metastatic group was 63.2% at 2 years and 36.5% at 5 years, and the progression free survival was 53.7% at 2 years and 37.8% at 5 years. High lactate dehydrogenase was found to be a significant poor prognostic factor (P = 0.001). Median OS for localized central EWS was 49.2 months and that for peripheral EWS was 24 months. Patients more than 20 years of age with non-metastatic disease had better OS compared to those with 15-20 years of age. CONCLUSION: Treatment of EWS requires a multidisciplinary approach with radical surgery and/or radiation to control local disease and multiagent chemotherapy to control systemic disease. Long-term follow-up is essential because of disease relapse and treatment-related complications.

Incidence of skeletal-related events in patients with Ewing sarcoma: An observational retrospective study in Japan.

BACKGROUND: Skeletal-related events (SREs), including the pathological fracture, surgical treatment or radiation of bone lesions, malignant spinal cord compression, hypercalcemia, are important considerations when managing metastatic bone tumors; however, owing to their rarity, the incidence of SREs in patients with Ewing sarcoma remains unknown. METHODS: We retrospectively reviewed the clinical data from 146 patients with Ewing sarcoma treated at a single institution from 2005 to 2019. The median age at diagnosis was 22.7 years. Fifty patients (34.2%) had metastatic disease at diagnosis. The primary outcome was the SRE-free rate among patients with Ewing sarcoma. Moreover, we identified the risk factors for SREs using univariate or multivariate analyses. RESULTS: During the observational period (median, 2.6 years), SREs occurred in 23 patients. Radiation to the bone, malignant spinal cord compression, and hypercalcemia were documented as the initial SREs in 12 patients (52.2%), 10 patients (43.5%), and one patient (4.3%), respectively. The SRE-free rate was 94.2 ± 2.0, 87.3 ± 3.0, and 79.6 ± 3.8% at 1, 2, and 3 years after the initial visit, respectively. Multivariate analysis revealed bone metastasis at diagnosis (hazard ratio [HR] = 4.41, p = 0.007), bone marrow invasion (HR = 34.08, p < 0.001), and local progression or recurrence after definitive treatment (HR = 3.98, p = 0.012) as independent risk factors for SREs. CONCLUSIONS: SREs are non-rare events that can occur during the treatment course for Ewing sarcoma, with an especially high incidence of malignant spinal cord compression. Patients with metastatic disease at diagnosis, especially in the bone or bone marrow, or with local progression or recurrence after definitive treatment, should be carefully monitored for the occurrence of SREs. The most effective methods to monitor the occurrence of SREs and new preventative therapies for SREs should be investigated in the future.

Genetic analyses identify evidence for a causal relationship between Ewing sarcoma and hernias.

Knowledge of Ewing sarcoma (EWS) risk factors is exceedingly limited; however, multiple small, independent studies have suggested a possible connection between hernia and EWS. By leveraging hernia summary statistics from the UK Biobank and a recently published genome-wide association study of EWS (733 EWS cases and 1,346 controls), we conducted a genetic investigation of the relationship of 5 hernia types (diaphragmatic, inguinal, umbilical, femoral, and ventral) and EWS. We discovered a positive causal relationship between inguinal hernia and EWS (OR 1.27, 95% confidence interval [CI] 1.01-1.59, and p = 0.041) through Mendelian randomization analysis. Further analyses suggested shared pathways through three genes: HMGA2, LOX, and FBXW7. Diaphragmatic hernia showed a stronger causal relationship with EWS among all of the hernia types (OR 2.26, 95% CI 1.30-3.95, p = 0.004), but no statistically significant local correlation pattern was observed. No evidence of a causal or genetic relationship was observed between EWS and the other three hernia types, including umbilical hernia, despite a previous report indicating an OR as high as 3.3. The finding of our genetic analysis provided additional support to the hypothesis that EWS and hernias may share a common origin.

Prognostic factors of sarcomas occurring in bone and joint: A SEER based study.

To clarify the epidemiology, treatment, and prognosis of sarcomas occurring in the bones and joints. The surveillance, epidemiology, and end results (SEER) 18 registries, comprising sarcoma diagnoses made between 2008 and 2014, were queried for sarcomas arising in bones or joints. Kaplan-Meier analysis, multivariate logistic regression analysis, Cox proportional hazards model, and nomograms were used to identify prognostic factors. 2794 patients aged from 1 to 99 (55.8% male) with microscopically confirmed diagnosed as sarcomas (including osteosarcoma, chondrosarcoma, Ewing sarcoma, and soft tissue sarcomas) which primary site limited to bone and joint were identified. Eight independent factors, including age, race, sex, tumor site, histology, pathology grade, tumor size, and total number of malignant tumors (TNOMT), were associated with tumor metastasis. Nine independent prognostic factors, including age (>=60 year, hazard ratio [HR] = 4.145, 95% confidence interval [CI], P < .001), sex (female, HR = 0.814, 95%CI, P = .007), tumor site (spine, HR = 2.527, 95%CI, P < .001), histology, pathology grade (undifferentiated, HR = 5.816, 95%CI, P < .001), tumor size (>=20 cm, HR = 3.043, 95%CI, P < .001), tumor extent (distant, HR = 4.145, 95%CI, P < .001), surgery (no performed, HR = 2.436, 95%CI, P < .001), and TNOMT (1, HR = 0.679, 95%CI, P < .001, were identified and incorporated to construct a nomogram for 2- and 5-year overall survival (OS). The calibration curve for the probability of survival showed good agreement between prediction by the nomogram and actual observation. The C-index of the nomogram for survival prediction was 0.814. Patients who received chemotherapy had a significantly decreased risk of death only for Ewing sarcoma, poorly differentiated tumors, undifferentiated tumors, and distant tumor invasion (P < .05). However, radiotherapy did not show significant differences in OS. This study presents population-based estimates of prognosis for patients with bone sarcomas and demonstrates the impact of age, race, sex, tumor site, histology, pathology grade, tumor size, tumor extent, surgery, radiotherapy, chemotherapy, and the TNOMT on OS. Moreover, the nomogram resulted in a more accurate prognostic prediction. However, in our study, radiotherapy showed no survival benefit, perhaps because detailed data on treatment factors were unavailable and which may have influenced the results.

Clinical features and outcomes of infantile soft-tissue sarcoma: A multicenter retrospective study in Beijing.

Background: Soft-tissue sarcomas during infancy are rare and understudied. With no data on this specific condition, we performed a retrospective study of infant-onset sarcomas based on a multi-institutional cohort in Beijing, China, collected over the past decade. We reviewed infantile soft-tissue sarcomas' clinical characteristics, treatments, and outcomes. Materials and Methods: The patients with soft-tissue sarcoma diagnosed from 0 to 12 months in four primary children's hospitals in Beijing from January 2010 to December 2019 were evaluated. Results: Fifty-one patients were enrolled, including 31 males and 20 females. The median age at the diagnosis was five months (range, 0-12), and seven (13.7%) patients were diagnosed in the first month of their life. Histologically, twenty-five patients were diagnosed with rhabdomyosarcoma (RMS), six were diagnosed with extraosseous Ewing sarcoma (EES), and twenty were diagnosed with nonrhabdomyosarcoma soft-tissue sarcoma (NRSTS). The treatment principles and details of RMS focused on reference to the Intergroup Rhabdomyosarcoma Study Group (IRSG) protocols. For EES and NRSTS, chemotherapy was prescribed according to children's oncology group protocols. The five-year EFS/OS rates of RMS were 26.4% ± 19.5%/56.2 ± 17.8%, the five-year EFS/OS rate of EES was 50% ± 20.4%, and the five-year EFS/OS of NRSTS was 85.2% ± 9.8%/100%. Conclusions: Infant-onset soft-tissue sarcoma is heterogeneous. The primary location of the abdominal or pelvic cavity of RMS and EWS was at a later stage and had a poorer prognosis. Multimodal therapy resulted in successful disease control for the majority of patients. Standardization of treatment protocols will facilitate care for such challenging conditions.

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.

Patient-reported neurocognitive function in adult survivors of childhood and adolescent osteosarcoma and Ewing sarcoma.

PURPOSE: Little is known regarding long-term neurocognitive outcomes in osteosarcoma and Ewing sarcoma (EWS) survivors despite potential risk factors. We evaluated associations among treatment exposures, chronic health conditions, and patient-reported neurocognitive outcomes in adult survivors of childhood osteosarcoma and EWS. METHODS: Five-year survivors of osteosarcoma (N = 604; median age 37.0 years) and EWS (N = 356; median age 35.0 years) diagnosed at < 21 years from 1970 to 1999, and 697 siblings completed the Childhood Cancer Survivor Study Neurocognitive Questionnaire and reported chronic health conditions, education, and employment. Prevalence of reported neurocognitive difficulties were compared between diagnostic groups and siblings. Modified Poisson regression identified factors associated with neurocognitive difficulties. RESULTS: Osteosarcoma and EWS survivors, vs. siblings, reported higher prevalences of difficulties with task efficiency (15.4% [P = 0.03] and 14.0% [P = 0.04] vs. 9.6%, respectively) and emotional regulation (18.0% [P < 0.0001] and 15.2% [P = 0.03] vs. 11.3%, respectively), adjusted for age, sex, and ethnicity/race. Osteosarcoma survivors reported greater memory difficulties vs. siblings (23.5% vs. 16.4% [P = 0.01]). Comorbid impairment (i.e., ≥ 2 neurocognitive domains) was more prevalent in osteosarcoma (20.0% [P < 0.001]) and EWS survivors (16.3% [P = 0.02]) vs. siblings (10.9%). Neurological conditions were associated with worse task efficiency (RR = 2.17; 95% CI = 1.21-3.88) and emotional regulation (RR = 1.88; 95% CI = 1.01-3.52), and respiratory conditions were associated with worse organization (RR = 2.60; 95% CI = 1.05-6.39) for EWS. Hearing impairment was associated with emotional regulation difficulties for osteosarcoma (RR = 1.98; 95% CI = 1.22-3.20). Patient report of cognitive difficulties was associated with employment but not educational attainment. CONCLUSIONS: Survivors of childhood osteosarcoma and EWS are at increased risk for reporting neurocognitive difficulties, which are associated with employment status and appear related to chronic health conditions that develop over time. IMPLICATIONS FOR CANCER SURVIVORS: Early screening, prevention, and treatment of chronic health conditions may improve/prevent long-term neurocognitive outcomes.

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.

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.

Assessment of Risk of Bias in Osteosarcoma and Ewing's Sarcoma Randomized Controlled Trials: A Systematic Review.

AIM: The aim of this study was to systematically assess the risk of bias in osteosarcoma and Ewing's sarcoma (ES) randomized controlled trials (RCT) and to examine the relationships between bias and conflict of interest/industry sponsorship. METHODS: An OVID-MEDLINE search was performed (1976-2019). Using the Cochrane Collaboration guidelines, two reviewers independently assessed the prevalence of risk of bias in different RCT design domains. The relationship between conflicts of interest and industry funding with the frequency of bias was examined. RESULTS: 73 RCTs met inclusion criteria. Prevalence of low-risk bias domains was 47.3%, unclear-risk domains 47.8%, and 4.9% of the domains had a high-risk of bias. Domains with the highest risk of bias were blinding of participants/personnel and outcome assessors, followed by randomization and allocation concealment. Overtime, frequency of unclear-risk of bias domains decreased (χ2 = 5.32, p = 0.02), whilst low and high-risk domains increased (χ2 = 8.13, p = 0.004). Studies with conflicts of interest and industry sponsorships were 4.2 and 3.1 times more likely to have design domains with a high-risk of bias (p < 0.05). CONCLUSION: This study demonstrates that sources of potential bias are prevalent in both osteosarcoma and ES RCTs. Studies with financial conflicts of interest and industry sponsors were significantly more likely to have domains with a high-risk of bias. Improvements in reporting and adherence to proper methodology will reduce the risk of bias and improve the validity of the results of RCTs in osteosarcoma and ES.

Identifying the Risk Factors and Estimating the Prognosis in Patients with Pelvis and Spine Ewing Sarcoma: A Population-Based Study.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: The study was designed to: (1) figure out risk factors of metastasis; (2) explore prognostic factors and develop a nomogram for pelvis and spine Ewing sarcoma (PSES). SUMMARY OF BACKGROUND DATA: Tools to predict survival of PSES are still insufficient. Nomogram has been widely developed in clinical oncology. Moreover, risk factors of PSES metastasis are still unclear. METHODS: The data were collected and analyzed from the Surveillance, Epidemiology, and End Results (SEER) database. The optimal cutoff values of continuous variables were identified by X-tile software. The prognostic factors of survival were performed by Kaplan-Meier method and multivariate Cox proportional hazards modeling. Nomograms were further constructed for estimating 3- and 5-year cancer-specific survival (CSS) and overall survival (OS) by using R with rms package. Meanwhile, Pearson χ2 test or Fisher exact test, and logistic regression analysis were used to analyze the risk factors for the metastasis of PSES. RESULTS: A total of 371 patients were included in this study. The 3- and 5-year CSS and OS rate were 65.8 ±â€Š2.6%, 55.2 ±â€Š2.9% and 64.3 ±â€Š2.6%, 54.1 ±â€Š2.8%, respectively. The year of diagnosis, tumor size, and lymph node invasion were associated with metastasis of patients with PSES. A nomogram was developed based on identified factors including: age, tumor extent, tumor size, and primary site surgery. The concordance index (C-index) of CSS and OS were 0.680 and 0.679, respectively. The calibration plot showed the similar trend of 3-year, 5-year CSS, and OS of PSES patients between nomogram-based prediction and actual observation, respectively. CONCLUSION: PSES patients with earlier diagnostic year (before 2010), larger tumor size (>59 mm), and lymph node invasion, are more likely to have metastasis. We developed a nomogram based on age, tumor extent, tumor size, and surgical treatments for determining the prognosis for patients with PSES, while more external patient cohorts are warranted for validation.Level of Evidence: 3.

Mobile Spine Osseous Sarcoma: Descriptive Epidemiological Analysis Based on a National Population-Based Study.

BACKGROUND: Primary osseous sarcomas of the mobile spine are rare bony tumors. Ewing sarcoma, chondrosarcoma, chordoma and osteosarcoma constitute the majority of primary bone sarcomas of the spine; however, other rare sarcoma tumors may also affect the spine. In order to perform an epidemiological study of theses tumors, national registries may help to evaluate data for populations with similar characteristics. METHODS: A population-based study was designed based on data from the Iran National Cancer Registry (INCR). All morphology codes (M-Code) of primary osseous sarcomas of the mobile spine (C-code 41.2) were derived and analyzed. RESULTS: Among 186 patients with primary osseous sarcomas of the mobile spine, 67.2% were men and 32.8% were women. The median (IQR) age was 37.0 (20.0-59.0) years and the age-standardized incidence rate (ASIR) was 0.37 per million. The majority of cases of Ewing sarcoma (29.5%) were observed in the age group 20-25 years. Among male patients with chondrosarcoma, the median age was 39.0 (30.0-50.0), while females showed a median age of 56.0 (50.0-59.0). The median age of patients with chordoma was 54.0 (47.0-63.0) years. The crude incidence rate of mobile spine osteosarcoma was 0.04 per million. CONCLUSION: Ewing sarcoma was the most frequent primary osseous sarcoma of the mobile spine. A male predilection was observed among all major sarcomas of the mobile spine. Ewing sarcoma in Iran affects the mobile spine in slightly older ages compared to other studies. Myxoid chondrosarcoma is the most frequent subtype of the mobile spine chondrosarcoma. Chordoma affects male in older ages compared to females. In contrast with other studies which showed a bimodal distribution of osteosarcoma of the spine including young adult and older age groups, 86% of cases in Iran were in the age group of 10-40 years.

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.

Evaluating Age-related Disparity of Outcomes in Ewing Sarcoma Patients Treated at a Pediatric Academic Medical Center.

Adolescent and young adult (AYA) patients with Ewing sarcoma have inferior survival compared with pediatric patients even when treated with similar regimens. Investigation into specific explanations is lacking. A retrospective chart review of Ewing sarcoma patients at a single institution was performed, and 104 patients were identified, 45 were 15 to 39 years of age (AYA cohort) and 59 younger than 15 years (pediatric cohort). AYA patients demonstrated more metastatic disease (50% vs. 24%, P=0.009), peripheral tumor location (64% vs. 41%, P=0.025), percentage of male patients (76% vs. 51%; P=0.010), and tumor size ≥5 cm (93% vs. 70%, P=0.016) than pediatric patients. Five-year overall survival was 77.7% and 53.0% and event-free survival was 68.7% and 40.6% for pediatric versus AYA, respectively. Similar rates of toxicity and chemotherapeutic dose adjustments were demonstrated. In this cohort, increased AYA patient mortality appears to be related to disease characteristics rather than treatment-related differences.

A nomogram for predicting overall survival in patients with Ewing sarcoma: a SEER-based study.

BACKGROUND: Ewing sarcoma, the second most frequent bone tumor in children and adolescents, is often presented with localized disease or metastatic-related symptoms. In this study, we aim to construct and validate a nomogram for patients with Ewing sarcoma to predict the 3- and 5-year overall survival (OS) based on the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: Demographic and clinic pathological characteristics of patients with Ewing sarcoma diagnosed between 2010 and 2015 were extracted from SEER database. Univariate and multivariate Cox analyses were carried out to identify the independent characteristics. The independent factors were further included into the construction of a nomogram. Finally, c-index and calibration curves were used to validate the nomogram. RESULTS: A total of 578 patients were enrolled into our analysis. The results of univariate Cox analysis showed that age, 7th AJCC stage, 7th AJCC T stage, 7th AJCC N stage, 7th AJCC M stage, metastatic status to lung, liver and bone were significant factors. Multivariate Cox analysis was performed and it confirmed age, N stage and bone metastasis as independent variables. Next, a nomogram was constructed using these independent variables in prediction to the 3- and 5-year OS. Furthermore, favorable results with c-indexes (0.757 in training set and 0.697 in validation set) and calibration curves closer to ideal curves indicated the accurate predictive ability of this nomogram. CONCLUSIONS: The individualized nomogram demonstrated a good ability in prognostic prediction for patients with Ewing sarcoma.

Two Cases of SARS-CoV-2 Infection in Pediatric Oncohematologic Patients in Spain.

Since December 2019, severe acute respiratory syndrome coronavirus 2 infection has spread worldwide. We all are concerned about immunocompromised children, especially hematologic and oncologic pediatric patients. We want to share our experience with 2 pediatric cancer patients with severe acute respiratory syndrome coronavirus 2 infection. Both presented mild disease and good outcome. No respiratory symptoms were identified, but both developed diarrhea, one probably secondary to lopinavir/ritonavir. Pediatric cancer patients may have milder disease than adults, but larger studies are needed to make conclusions.

Evaluation of factors affecting survival rate in primary bone sarcomas with extremity and pelvis involvement.

OBJECTIVE: This study is an evaluation of the overall survival rate and factors affecting survival in patients with osteosarcoma, chondrosarcoma, or Ewing's sarcoma. This study aimed to determine the effect of factors related to the preoperative period, patient, tumor, treatment, and postoperative period on survival. METHODS: A total of 114 patients (64 male and 50 female) with osteosarcoma, chondrosarcoma, or Ewing's sarcoma treated between 2005 and 2013 were included in this study. All the patients received standard treatment and were followed up regularly. In all, 44 cases of (conventional and telangiectatic) osteosarcoma, 30 cases of Ewing's sarcoma, and 40 cases of high-grade chondrosarcoma were identified using the Bone and Soft Tissue Tumor Registry. Gender, age, tumor size and localization, pathological fractures, histopathological type, grade, surgical treatment, adjuvant treatments, relapse of the disease, and postoperative complication data were obtained from follow-up forms. The learning curve of institutional expertise was also evaluated. The patient survival rate was calculated using the Kaplan-Meier method, and log-rank statistical methods were used to compare survival rates. RESULTS: The mean length of survival of the patients was 72 months. There was a 56% 5-year survival rate, and the event-free survival rate was 53%. The survival of patients with Ewing's sarcoma whose prodromal period was less than 12 weeks was significantly higher than that of the other groups (p=0.031). The survival of patients with tumor size greater than 150 cc, with local recurrence and distant metastases was low for all groups. Survival rates were significantly lower in osteosarcoma and Ewing's sarcoma patients with stage III tumor or metastasis at diagnosis. The survival of patients with osteosarcoma diagnosed between 2010 and 2013 was significantly higher than that of the earlier group (p=0.02). CONCLUSION: Decreasing the prodromal period (early diagnosis) can improve survival by preventing the local and systemic spread of the tumor. Increase in the surgical experience is likely to have a positive effect on survival rates, especially for patients with osteosarcoma. The relapse of the disease is a poor prognostic factor for survival despite aggressive surgery and adjuvant therapies. LEVEL OF EVIDENCE: Level IV, Therapeutic study.

Risk factors for metastasis and poor prognosis of Ewing sarcoma: a population based study.

BACKGROUND: This study is to determine the risk factors for metastasis of Ewing sarcoma (ES) patients in SEER database. Then explore clinicopathological factors associated with poor prognosis. Furthermore, develop the nomogram to predict the probability of overall survival and cancer-specific survival METHODS: Thus, we collected clinicopathological data of ES patients in SEER database, and then used chi-square test and logistic regression to determine risk factors associated to metastasis. We also did survival analysis including Kaplan-Meier curve and Cox proportional hazard model to explore the risk factors associated to overall survival and cancer-specific survival, and then developed the nomogram to visualize and quantify the probability of survival. RESULTS: After statistics, we find that patients with older ages (11-20 years old: OR = 1.517, 95% confidence interval [CI] 1.033-2.228, p = 0.034; 21-30 years old: OR = 1.659. 95%CI 1.054-2.610, p = 0.029), larger tumor size (> 8 cm: OR = 1.914, 95%CI 1.251-2.928, p = 0.003), and pelvic lesions (OR = 2.492, 95%CI 1.829-3.395, p < 0.001) had a higher risk of metastasis. ROC curves showed higher AUC (0.65) of combined model which incorporate these three factors to predict the presence of metastasis at diagnosis. In survival analysis, patients with older ages (11-20 years: HR = 1.549, 95%CI 1.144-2.099, p = 0.005; 21-30 years: HR = 1.808, 95%CI 1.278-2.556, p = 0.001; 31-49 years: HR = 3.481, 95%CI 2.379-5.094, p < 0.001; ≥ 50 years: HR = 4.307, 95%CI 2.648-7.006, p < 0.001) , larger tumor size (5-8 cm: HR = 1.386, 95%CI 1.005-1.991, p = 0.046; > 8 cm: HR = 1.877, 95%CI 1.376-2.561, p < 0.001), black race (HR = 2.104, 95%CI 1.296-3.416, p = 0.003), and wider extension (regional: HR = 1.373, 95%CI 1.033-1.823, p = 0.029; metastatic: HR = 3.259, 95%CI 2.425-4.379, p < 0.001) were associated with worse prognosis. Chemotherapy was associated with better prognosis (HR = 0.466, 95%CI 0.290-0.685, p < 0.001). The nomogram which developed by training set and aimed to predict OS and CSS showed good consistency with actual observed outcomes internally and externally. CONCLUSION: In conclusion, tumor size and primary site were associated with distant metastasis at diagnosis. Age, tumor size, primary site, tumor extent, and chemotherapy were associated with overall survival and cancer-specific survival. Nomogram could predict the probability of OS and CSS and showed good consistency with actual observed outcomes internally and externally.