Clinical features and outcomes in patients with extraskeletal Ewing sarcoma

Case report and literature review: A young man with giant intra-abdominal Ewing sarcoma

RATIONALE

Extraosseous Ewing sarcoma (EES) is a rare manifestation within the Ewing sarcoma tumor family (ESFT). Its clinical manifestations lack specificity, intestinal obstruction is the main symptom but can also present with abdominal pain, gastrointestinal bleeding, and other discomforts, making it prone to misdiagnosis as intestinal mesenchymal tumor.

PATIENT CONCERNS

A 29-year-old male was admitted to the hospital with intestinal obstruction symptoms and abdominal CT suggesting "left abdominal occupation."

DIAGNOSIS

The patient was initially misdiagnosed as intestinal mesenchymal tumor, and was later definitively diagnosed as abdominal Ewing sarcoma by postoperative pathology and genetic testing.

INTERVENTIONS

Due to the patient's surgical indication, surgical resection with exploratory laparotomy was performed and then the patient underwent systemic chemotherapy.

OUTCOMES

Intraoperatively, we found a 15-cm tumor originating from the proximal jejunum, with invasion into the peritoneum, duodenum, jejunum, and colon. Finally, the pathological report revealed Ewing sarcoma.

LESSONS

Giant abdominal Ewing sarcoma with a diameter of 15 cm is rare. Considering postoperative pathology and genetic testing, abdominal Ewing sarcoma was suspected. The patient was successfully treated using surgery.

Clinicopathological and molecular genetic analysis of 13 cases of primary retroperitoneal Ewing sarcoma

Retroperitoneal Ewing sarcomas (RES) are very rare and mostly described in case reports. The purpose of this study was to retrospectively analyze the clinicopathology, molecular characteristics, biological behavior, and therapeutic information of 13 cases of primary RES with immunohistochemical staining, fluorescence in situ hybridization, RT-PCR and NGS sequencing detection techniques. The thirteen patients included eight males and five females with a mean age of 34 years. Morphologically, the tumors were comprised of small round or epithelial-like cells with vacuolated cytoplasm (6/13,46 %) arranged in diffuse, nested (8/13,62 %) and perivascular (7/13,54 %) patterns. Unusual morphologic patterns, such as meningioma-like swirling structures and sieve-like structures were relatively novel findings. Immunohistochemical studies showed CD99 (12/13; 92 %), CD56 (11/13; 85 %), NKX2.2 (9/13; 69 %), PAX7 (10/11;91 %) and CD117(6/9;67 %) to be positive.12 cases (92 %) demonstrated EWSR1 rearrangement and 3 cases displayed EWSR1::FLI1 fusion by FISH. ERCC4 splice-site variant, a novel pathogenic variant, was discovered for the first time via RNA sequencing. With a median follow-up duration of 14 months (6 to 79 months), 8/13 (62 %) patients died, while 5/13(38 %) survived. Three cases recurred, and five patients developed metastasis to the liver (2 cases), lung (2 cases) and bone (1 case). RES is an aggressive, high-grade tumor, prone to multiple recurrences and metastases, with distinctive morphologic, immunohistochemical, and molecular genetic features. ERCC4 splicing mutation, which is a novel pathogenic variant discovered for the first time, with possible significance for understanding the disease, as well as the development of targeted drugs.

Impact of age on safety of Busulfan-Melphalan followed by autologous hematopoietic stem-cell transplantation versus standard chemotherapy in the patients of the EURO-E.W.I.N.G. 99 and Ewing 2008 clinical trials

INTRODUCTION

Ewing sarcoma (ES), is a rare cancer affecting children, adolescents and adults. After VIDE (vincristine-ifosfamide-doxorobucin-etoposide) induction chemotherapy, Busulfan-Melphalan (BuMel) high-dose chemotherapy followed by autologous hematopoietic stem cells transplantation improved outcomes in unfavourable localized ES, but with more toxicities than conventional chemotherapy (VAI: Vincristine-dactinomycin-Ifosfamide). We evaluated whether the risk of acute toxicity associated with BuMel compared to VAI varied according to age in patients recruited in the R2Loc and R2Pulm randomised trials of the Euro-E.W.I.N.G.99 and Ewing-2008 trials.

METHODS

We included patients with a localized high-risk disease, or pulmonary or pleural metastasis. We analysed the risk of severe toxicity according to randomised treatment group (VAI versus BuMel) and age group (<12 years, 12-17 years, 18-24 years, ≥25 years). We evaluated the heterogeneity of treatment effects by age group using interaction terms in logistic multivariable models.

RESULTS

The analysis included 243 patients treated with VAI and 205 with BuMel. Overall, BuMel was associated with a higher risk of severe acute toxicity than VAI particularly haematological, gastrointestinal, liver, sinusoidal occlusive syndrome, and infections. Severe haematological toxicity and lower general condition were significantly more frequent in younger patients, whatever treatment. We did not observe any significant heterogeneity in terms of the excess risk of severe toxicities associated with BuMel compared to VAI according to age group.

CONCLUSION

The excess of acute toxicity associated with BuMel compared to VAI does not vary significantly with age, suggesting the feasibility of BuMel across all age groups.

The Role of Deubiquitinating Enzymes in Primary Bone Cancer

Bone is a living, intricate, and dynamic tissue providing locomotion and protection of the body. It also performs hematopoiesis and mineral homeostasis. Osteosarcoma (OS), Ewing sarcoma (ES), and chondrosarcoma (CS) are primary bone cancers. OS and ES mostly develop in younger individuals, and CS generally develops in adults. Ubiquitination regulates numerous cellular processes. The deubiquitinating enzymes (DUBs) detach the ubiquitin molecules from the ubiquitin labeled substrate, altering ubiquitinated protein functions and regulating protein stability via various signaling pathways. Protein homeostasis and bone remodeling are both crucially influenced by the UPS. Recently, there have been several reports on DUBs involved in bone homeostasis and various bone disorders through the regulation of osteoblasts and osteoclasts via NF-κB, Wnt/β-catenin, TRAF6, TGFβ, ERK1/2, and PI3K/Akt pathways. However, DUBs regulating function in bone homeostasis is still in its infancy. Here, we summarized several recent identifications on DUBs, with a focus on their role in bone cancer progression. Therefore, the study attempts to summarize association with the expression level of DUBs as key factors driving bone cancers and also provide new insights on DUBs as key pharmacologic targets for bone cancer therapeutics.

Pediatric Axial Ewing Sarcoma: A Retrospective Population-Based Survival Analysis

INTRODUCTION

Ewing sarcomas of the axial skeleton represent a notable challenge for clinicians because of their aggressive presentation and tendency to obstruct neurovascular structures; however, little data exist regarding axial tumors in children. This study is the first population-based analysis assessing treatment regimens for axial Ewing sarcomas and their effects on cancer-specific survival and overall survival (OS).

METHODS

Data from 2004 to 2019 were collected for all patients aged 1 to 24 years from the Surveillance, Epidemiology, and End Results (SEER) database. Primary groups included pelvic tumors, thoracic tumors, and vertebral tumors. Chi-squared and Kaplan-Meier tests were used to assess associations between demographic variables, clinical and treatment characteristics, and patient survival.

RESULTS

Pelvic tumors were most common, and 49.7% received chemotherapy/radiation. Vertebral tumors were least common, and 56.7% received chemotherapy/surgery/radiation. 53.5% of thoracic tumors received chemotherapy/surgery. Surgery was most common for thoracic tumors (80.2%) and rare for pelvic tumors (38.9%). Radiation therapy was most common for vertebral tumors (83.6%) and least common for thoracic tumors (36.0%). Pelvic tumors exhibited the lowest OS (1-year, 5-year, and 10-year OS: 96%, 70%, and 59%), followed by thoracic tumors (1-year, 5-year, and 10-year OS: 97%, 79%, and 66%) and vertebral tumors (1-year, 5-year, and 10-year OS: 92%, 77%, and 68%).

CONCLUSION

This study underpins the importance of both early detection and chemotherapy-based multimodal therapy in the treatment of axial Ewing sarcoma in a pediatric population. A comparatively large decline in OS was observed between 5 and 10 years for patients with thoracic tumors, and this cohort's 10-year OS has not improved when compared with a similar SEER cohort from 1973 to 2011. Despite a growing body of research supporting definitive radiation therapy, a notable portion of patients with pelvic Ewing sarcoma did not receive radiation, representing an unmet need for this population.

Extraosseous Ewing Sarcoma in a 28-Year-Old Male: A Case Report and Literature Review

Ewing sarcoma (ES) is an uncommon and highly aggressive bone malignancy that predominantly occurs in children and young adults. Extraosseous Ewing sarcoma (EES), an even rarer variant, can present in the soft tissues instead of bone. In this case report, we detail a previously healthy 28-year-old male presenting with an isolated enlarged left inguinal lymph node, subsequently diagnosed as EES. The patient presented with a three-month history of a non-tender, gradually enlarging lump in the left groin. Fine needle aspiration revealed a small round blue cell tumor with a high Ki-67 score, and subsequent excisional biopsy identified a rare genetic fusion mutation. Postoperative positron emission tomography (PET)/computed tomography (CT) scan did not show any fludeoxyglucose F18 (FDG) uptake lesions to suggest residual malignancy. The patient is currently awaiting chemotherapy. Throughout the discussion of this case, we highlight the importance of considering EES in the differential diagnosis of isolated lymph node enlargement, the role of genetic testing in diagnosis, and the treatment modalities offered.

Primary intradural Extraosseous Ewing's sarcoma of the cauda equina: A case report and literature review

Intradural Extraosseous Ewing sarcoma (IEES) is an infrequent occurrence. We report a case of a 66-year-old male who presented with a 2-month history of low back pain and bilateral S1 sciatica, with acute sphincter dysfunction. Imaging studies revealed an intradural extramedullary lesion in the cauda equina spanning from level L4 to S1. The patient underwent partial removal of the intradural lesion. Histopathological examination showed the presence of small round cells, which were consistent with Ewing Sarcoma. The patient was then treated with targeted radiation therapy and chemotherapy. The rarity of IEES in this specific location underscores the significance of evaluating and managing patients with intradural spinal tumors with careful consideration of this diagnosis. To further investigate this condition, we conducted a thorough review of the literature on IEES involving the lumbar spine and cauda equina. Our analysis revealed that patients with this condition frequently exhibit rapidly progressive neurological symptoms likely attributed to hemorrhagic transformation. This characteristic may serve as a distinguishing factor from other lesion types, particularly benign ones. Our study provides a comprehensive summary that can offer direction for clinical management in comparable uncommon and novel cases.

Ewing Sarcoma of the Ethmoid Sinus in an Adult

Extraskeletal Ewing sarcoma (EES) is a relatively rare primary tumor of the soft tissues predominantly affecting men in the second and third decades of life. They are a less common form of the cancerous growth known as an Ewing sarcoma, which occurs in bones or soft tissue such as cartilage. Head and neck ESS can require intervention including endoscopic sinus surgery, septoplasty, inferior turbinectomy, and left internal nasal valve repairs with septal cartilage This is a case report on an unusual presentation of ESS in the sinonasal region.

Primary extraskeletal intradural Ewing sarcoma with acute hemorrhage: a case report and review of the literature

BACKGROUND

Spinal cord tumors present a challenge in diagnosis and treatment due to their varied histopathological characteristics. While Ewing sarcoma is a rare malignant tumor typically originating from skeletal bone, cases of primary intradural extraskeletal Ewing sarcoma are exceptionally rare. The similarity of its presentation to other spinal tumors further complicates its identification and management.

CASE PRESENTATION

We report a case of a 58-year-old Palestinian male with intradural extraskeletal lumbar Ewing sarcoma. The patient initially presented with lower back pain and bilateral S1 radiculopathy, with more severe symptoms on the left side. Magnetic resonance imaging revealed a 7 cm oval-shaped mass with homogeneous contrast enhancement, obstructing the spinal canal from L3/L4 to L5/S1 levels. Initially, a myxopapillary ependymoma was suspected, but the patient's sensory and motor functions suddenly deteriorated during hospitalization. Repeat magnetic resonance imaging indicated heterogeneous contrast enhancement, indicating acute intratumoral hemorrhage. Consequently, the patient underwent emergent L3-L5 laminotomy, with successful gross total resection of the tumor. Histopathological and immunohistochemical analyses confirmed the diagnosis of intradural extraskeletal Ewing sarcoma. Adjuvant therapy was administered to minimize the risk of local recurrence or distant metastasis. A systematic review of relevant literature, along with retrospective analysis of medical records, operative reports, radiological studies, and histopathological findings of similar cases, was also conducted.

CONCLUSIONS

Intradural extraskeletal Ewing sarcoma is an infrequently encountered condition in adult patients, emphasizing the importance of considering it in the differential diagnosis of spinal tumors. Surgeons must possess a comprehensive understanding of this rare entity to ensure accurate staging and optimal management, particularly in the early stages when prompt intervention may improve prognosis.

Primary Cervical Extraosseous Ewing's Sarcoma Originated from the Sternocleidomastoid Muscle: A Case Report and Review of the Literature

Extraosseous Ewing's sarcoma is extremely rare in the soft tissues of the neck, especially in the sternocleidomastoid muscle. It usually manifests clinically as a rapidly growing mass that shows great potential for local spread. The aim of this paper is to present a rare case of еxtraosseous Ewing's sarcoma in the sternocleidomastoid muscle. To the best of our knowledge, this is the first case of extraskeletal Ewing's sarcoma at this location. The patient was admitted to our clinic because of a neck tumefaction. The computerized tomography finding showed a tumor mass, most of which was in the V region of the neck, measuring 40 × 27 × 35 mm. Pathohistological and immunohistochemical findings showed that it was Ewing's sarcoma. Unfortunately, the patient passed away nine months after the initial diagnosis. Extraosseous Ewing sarcoma is a rare, fast-growing malignant tumor manifesting histomorphological similarities to bone Ewing's sarcoma. Most reports state that extraosseous Ewing sarcoma has a worse prognosis than skeletal. Extraosseous Ewing sarcoma should be borne in mind in the differential diagnosis of soft tissue tumors of the neck.

Twenty-year outcome of prevalence, incidence, mortality and survival rate in patients with malignant bone tumors

Malignant bone tumors are a group of rare malignant tumors and our study aimed to update the recent epidemiologic estimates based on the Surveillance, Epidemiology and End Results database. Patients diagnosed with malignant bone tumors from 2000 to 2019 were included and their characteristics were retrospectively described. The limited-duration prevalence, annual age-adjusted incidence and mortality were calculated, and the annual percentage changes were analyzed to quantify the rate change. Finally, observed survival and relative survival rate were illustrated. Subgroup analysis across tumor type, age, gender, tumor Grade, primary tumor site and stage was also performed. As for results, a total of 11 655 eligible patients with malignant bone tumor were selected. Osteosarcoma was the most common tumor type, followed by chondrosarcoma, Ewing sarcoma and chordoma. The estimated limited-duration prevalence of malignant bone tumors increased from 2000 (0.00069%) to 2018 (0.00749%). Steady age-adjusted incidence was observed in all patients during the study period while the highest rate occurred in osteosarcoma. Mortality rates differed in subgroups while elder patients (older than 64 years) presented the highest mortality rate compared to other age groups. In all bone tumors, the 10-year observed survival and relative survival rates were 58.0% and 61.9%, respectively. Chondrosarcoma patients had the best survival outcome, followed by osteosarcoma, Ewing sarcoma, chordoma and other bone tumors. In conclusion, different epidemiologic performance in incidence and mortality was observed across tumor type as well as other demographic and clinicopathological variables, which provide potential suggestion for further adjustment of medical resource.

Primary intradural extraosseous Ewing's sarcoma of the L3 nerve root: illustrative case

BACKGROUND

Ewing's sarcoma is an uncommon, aggressive malignancy that typically presents as an osseous lesion, most commonly in children and adolescents. Very rarely Ewing's sarcoma can present as an intradural extramedullary mass mimicking more common tumors.

OBSERVATIONS

A 32-year-old female had a left L3 nerve root-associated lesion identified in the setting of recent-onset radiculopathy. Contrast-enhanced magnetic resonance imaging of the lumbar spine was favored to demonstrate a schwannoma or neurofibroma. Hemilaminectomy, facetectomy, and resection of the mass led to improved radiculopathy and a tissue diagnosis of Ewing's sarcoma. Immediate referral to medical oncology facilitated expeditious initiation of adjuvant chemotherapy and radiation.

LESSONS

The differential diagnosis for newly identified nerve root-associated tumors should remain broad, including common benign pathologies and rare malignant entities. Tissue remains the gold standard for diagnosis, as preoperative imaging suggested a nerve sheath tumor. Malignant pathologies such as Ewing's sarcoma must be considered, especially in the setting of rapidly progressive symptoms or interval growth on serial imaging. Early diagnosis allows for the timely initiation of comprehensive oncological care. Long-term multidisciplinary follow-up is necessary for the surveillance of disease progression.

Clinicodemographic characteristics of extraosseous ewing sarcoma: A comparative meta-analysis of pediatric and adult patients

Background

Evidence suggests different presentation patterns and prognosis of extraosseous Ewing Sarcoma (EES) based on age. Thus, we carried out this study to test the difference between children and adult EES cases regarding clinicodemographic characteristics and prognosis.

Methods

A total of 4 databases were explored yielding 18 relevant studies for data synthesis. Outcomes included the comparison of demographic and clinical characteristics as well as prognosis between children and adults with EES. Log odds ratio (logOR) and its 95% confidence interval (CI) were pooled across studies. Statistical models/methods were selected based on heterogeneity.

Results

Our analysis included a total of 1261 children and 1256 adults. When we compared these two age categories, we did not observe a significant difference in the risk of developing EES [logOR = -0.13; 95% CI: -0.65: 0.39; I2 = 88.42%]. No significant differences regarding gender, tumor location, and size (≤5 vs. >5 cm), EWSR1 positivity, or management modality. We did not observe significant difference regarding clinical outcomes, such as 5-year overall survival and event-free survival, recurrence, mortality, no evidence of disease, and secondary metastasis.

Conclusions

Our findings highlight the absence of an association between the age category of patients and the incidence of EES, as well as its clinical outcomes.

Extra-skeletal Ewing's sarcoma of the leg with multiple skeletal and pulmonary metastases: A rare pediatric case report

Being the second most common malignant bone tumor in children and young adults, Ewing's sarcoma can also occur as a primary soft-tissue tumor called extraosseous or extra-skeletal Ewing's sarcoma. It is a rare entity, especially in the pediatric population. We report the case of an adolescent who presented to our department for lower extremity magnetic resonance imaging to explore leg swelling. It revealed an extra-skeletal Ewing's sarcoma with multiple bone metastases. By reporting this case, we also review the literature on this rare abnormality.

Ewing sarcoma treatment: a gene therapy approach

Ewing sarcoma (ES) is an aggressive malignant tumor, characterized by non-random chromosomal translocations that produce fusion genes. Fusion genes and fusion protein products are promising targets for gene therapy. Therapeutic approaches and strategies vary based on target molecules (nucleotides, proteins) of interest. We present an extensive literature review of active molecules for gene therapy and methods of gene therapy delivery, both of which are necessary for successful treatment.

Practical Management of Adult Ultra-Rare Primary Retroperitoneal Soft Tissue Sarcoma: A Focus on Perivascular Epithelioid Tumours and Extraosseous Ewing Sarcoma

With the exception of well-differentiated liposarcoma, dedifferentiated liposarcoma, leiomyosarcoma, solitary fibrous tumour, malignant peripheral nerve sheath tumour, and undifferentiated pleomorphic sarcoma, the majority of the ≈70 histologic subtypes of retroperitoneal sarcoma are defined as 'ultra-rare' sarcomas, with an incidence of ≤1-5/1,000,000 persons/year. For most of these ultra-rare RPS subtypes, diagnosis and treatment follows international guidelines for the management of more common RPS histologies, with en bloc surgical resection as the mainstay of curative treatment, and enrolment in clinical trials where possible. Because the treatment of RPS is heavily driven by histology, the surgeon must be familiar with specific issues related to the diagnosis and management of ultra-rare sarcoma subtypes. Expert radiological and surgeon reviews are required to differentiate similarly presenting tumours where surgery can be avoided (e.g., angiomyolipoma), or where upfront systemic therapy is indicated (e.g., extraosseous Ewing's sarcoma). Thus, the management of all retroperitoneal sarcomas should occur at a sarcoma referral centre, with a multidisciplinary team of experts dedicated to the surgical and medical management of these rare tumours. In this focused review, we highlight how diagnosis and management of the ultra-rare primary RPS histologies of malignant perivascular epithelioid cell tumour (PEComa), extraosseous Ewing sarcoma (EES), extraosseous osteosarcoma (EOS), and rhabdomyosarcoma (RMS) critically diverge from the management of more common RPS subtypes.

Ewing's sarcoma of the duodenum: a rare clinical condition managed with surgical resection

A man in his 40s with no medical history presented with right-sided abdominal and chest pain. A CT scan of the abdomen demonstrated a 7.7 cm heterogeneous mass arising from the second part of the duodenum. Oesophagogastroduodenoscopy confirmed a malignant-appearing duodenal lesion, with biopsy showing features consistent with small cell carcinoma. The patient underwent three cycles of neoadjuvant chemotherapy, followed by elective Kausch-Whipple pancreaticoduodenectomy. A combination of immunohistochemistry and molecular studies confirmed the diagnosis of a rare Ewing's sarcoma tumour originating from the duodenum with invasion into the duodenal lumen. The patient recovered well from surgery and remains disease-free 18 months following resection.

Imaging of pediatric bone tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Malignant primary bone tumors are uncommon in the pediatric population, accounting for 3%-5% of all pediatric malignancies. Osteosarcoma and Ewing sarcoma comprise 90% of malignant primary bone tumors in children and adolescents. This paper provides consensus-based recommendations for imaging in children with osteosarcoma and Ewing sarcoma at diagnosis, during therapy, and after therapy.

Unusual Manifestation of Extraosseous Ewing Sarcoma: Report of 3 Cases

Ewing sarcoma (ES), described as a diffuse endothelioma of the bone, is divided into two categories: osseous and extraosseous, which mainly affects adolescents. Extraosseous Ewing Sarcomas (EES) are rare tumors originating from soft tissues. Their clinical presentation depends mainly on the primary location of the tumor and are highly chemosensitive and radiosensitive. The purpose of this study was to describe the clinical characteristics and outcomes of 3 children with EES and uncommon presentation treated in our Unit. The diagnosis of EES was confirmed by biopsy and cytogenetic analysis with fluorescence in situ hybridization (FISH). Surgical excision was planned as primary treatment, followed by adjuvant chemotherapy according to EURO-E.W.I.N.G protocol. To date, all patients are alive, 1, 3 and 4 years after completion of treatment, with no signs of recurrence or metastasis.

Clinical characteristics of primary cutaneous and subcutaneous Ewing sarcoma

OBJECTIVE

Given the rarity of cutaneous/subcutaneous Ewing sarcoma, their clinical characteristics remain poorly understood. In this study, we aimed to analyse the clinical characteristics of patients with cutaneous/subcutaneous Ewing sarcoma and review the treatment strategy.

METHODS

We reviewed the clinical data of 154 patients with Ewing sarcoma who were treated at our hospital between 2005 and 2019. Amongst these patients, 21 patients with cutaneous/subcutaneous Ewing sarcoma were analysed. As a basic strategy, patients with localized disease received intensive chemotherapy (vincristine-doxorubicin-cyclophosphamide/ifosfamide-etoposide), followed by definitive surgery with or without radiotherapy. In total, 15 patients underwent pre-diagnostic resection with macroscopic residue (seven patients) or non-macroscopic residue (eight patients) before intensive chemotherapy.

RESULTS

The median tumour length of the measurable lesions was 3.2 cm, and the ratio of metastasis was significantly lower than the Ewing sarcoma of other anatomical sites (10% vs. 37%, P = 0.013). Despite the pre-diagnostic resection, local recurrence after additional resection and/or adjuvant radiotherapy did not occur in any of the patients with localized disease. Overall survival was significantly higher in patients with cutaneous/subcutaneous Ewing sarcoma than in patients with Ewing sarcoma of other anatomical sites (hazard ratio = 0.33, P = 0.013). The event-free survival rate of cutaneous/subcutaneous Ewing sarcoma was also superior to that of Ewing sarcoma of other anatomical sites (hazard ratio = 0.35, P = 0.01).

CONCLUSIONS

Patients with cutaneous/subcutaneous Ewing sarcoma may have better prognosis than those with Ewing sarcoma at other anatomical sites. Although pre-diagnostic resection without appropriate investigations is not recommended, local control may be recovered by using a combination of additional resection, chemotherapy and radiotherapy.

Extraskeletal Ewing's sarcoma of the head and neck region in pediatric patients: A case report and literature review

INTRODUCTION AND IMPORTANCE

Extraskeletal Ewing's sarcoma (EES) is a collection of malignant cells that appear small and round and occur mostly in pediatrics and adolescence. Head and neck EES tumors are considered rare and require multidisciplinary care to achieve ideal results in management.

CASE PRESENTATION

A 14-year-old boy who complained of a mass protruding from the back of his neck which gradually increased in size in the last few months prior to the diagnosis. He was referred to a pediatric otolaryngology clinic with a one-year history of chronic painless nape swelling. Ultrasound prior to the referral was done and the findings revealed a well-defined rounded hypoechoic lesion with internal vascularity. MRI was done and the impression was a large subcutaneous, well defined enhancing soft tissue lesion which raised the suspicion of sarcoma. The multidisciplinary team decision was to go for complete resection with a free margin followed by chemoradiation postoperatively. No evidence of recurrence was detected throughout the follow-up.

CLINICAL DISCUSSION

The literature review included ages of the pediatric group from 4 months up to 18-year-old. Clinical features are highly dependable on the size and site of the lesion. Complete resection of the tumor plays an important role in the local control and prognosis.

CONCLUSION

We present a rare case of extraskeletal Ewing's sarcoma of the nape. Computed tomography and magnetic resonance imaging are frequently used as imaging modalities in evaluating and diagnosing EES. Management commonly includes surgery with adjuvant chemotherapy to decrease recurrence and prolong the survival rate.

A Case of Extraskeletal Ewing Sarcoma Treated With Wide Local Excision With Latissimus Dorsi Flap and Systemic Therapy

Extraskeletal Ewing sarcoma (EES) is a rare tumor of the soft tissue that looks the same as skeletal Ewing sarcoma (ES). A male in his 50s was diagnosed with extraskeletal Ewing sarcoma (EES) of the right shoulder, which had infiltrated the muscles around the shoulder joints. Although uncommon, all members of the ES family of tumors, including EES, were treated following the same general protocol for sarcoma tumors. Due to the significant tumor size in this patient and local invasion, wide local excision and a latissimus dorsi flap were required. This case highlighted the management of EES, including the surgical removal of the mass on the right shoulder, followed by chemotherapy, which led to a successful outcome.

A rare case of a peripheral Ewing sarcoma primitive neuroectodermal tumor of pelvic origin

Primitive neuroectodermal tumors (PNET) represent malignant neuroectodermal tumors composed of small round cells. They can be differentiated between originating from the peripheral nervous system or the central nervous system. Peripheral PNET (pPNET) can be further subclassified as one of the Ewing family tumors (EFT). Although rare, EFT can originate in the female genital tract and pelvic region. Here, we present a case of a middle-aged female with PNET masses in her uterus, abdomen, and hepatic lobes. We discuss the diagnostic modalities, including immunohistochemistry, histopathology, and imaging findings associated with this rare malignancy.

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.

Prognostic Factors and Clinical Outcomes in Extraskeletal Ewing Sarcoma: A Cohort Study

BACKGROUND

Extraskeletal Ewing sarcoma (ESE) is a lesser-known, rarer counterpart of Ewing sarcoma of bone. This single-center study sought to evaluate the prognosticators and outcomes following multimodality therapy in patients with ESE.

METHODS

Forty-seven patients with ESE, treated between 2013 and 2018 with a standardized protocol and multimodality therapy using established doxorubicin-based regimens, were followed-up to assess outcomes.

RESULTS

Median age at diagnosis was 20 (range 7-56) years, and 57.4% were male. Median tumor size was 7 (range 2-21) cm. The symptom-duration ranged from 1 to 8 (median 4) months. Tumor-site was trunkal in 61.7%, extremity in 23.4%, and head and neck 14.9%. Of the 35 patients with nonmetastatic disease at presentation, 13 underwent upfront surgery. The rest received chemotherapy followed by local treatment, which was surgical in 15 and radiotherapy in 5. At median follow-up of 24 (range 5-98) months, 55.3% patients had experienced events, and 29.8% had died of progressive disease. Three-year event-free survival was 41.1%, and overall survival was 53%. On univariate analysis, trunkal location, upfront surgery, and positive surgical margins were associated with inferior EFS. Trunkal tumors and upfront surgery were also associated with poorer OS. On multivariate analysis, trunkal location and margin-positive resections retained statistical significance for adverse EFS.

CONCLUSIONS

Unless clearly resectable upfront, ESE should be downstaged with chemotherapy before local treatment. A margin-negative resection should be the objective when performing surgery. Definitive radiotherapy is an alternative in tumors not amenable for complete excision or when anticipated postoperative morbidity precludes radical surgery.

Primary intradural extramedullary Ewing sarcoma in the lumbar area: A case report

Primary intradural extramedullary Ewing sarcoma (IEES) is the rarest type of Ewing sarcoma. Extreme caution is required for the diagnosis of IEES because benign intradural spinal tumors can be mistaken for IEES in the early stages of imaging and clinical evaluation. IEES tumors have no standardized treatment guidelines because of the lack of research on the therapeutic aspects of these tumors. Herein, we present a case of primary IEES in a male adolescent with a fast progression of the disease. Diagnosis of IEES was suspected with imaging (computed tomography scan and lumbosacral magnetic resonance imaging) and was confirmed with histology and immunohistochemistry (positive reactivity for CD99 and FLI1). He was successfully treated with surgical intervention with no radiotherapy or chemotherapy. Imaging studies are helpful in making the initial diagnosis of intradural extramedullary Ewing sarcoma. Surgery is considered to be a successful method of treatment for this condition.

Ewing Sarcoma as Secondary Malignant Neoplasm-Epidemiological and Clinical Analysis of an International Trial Registry

Ewing sarcoma (EwS) is the second most common bone and soft tissue tumor, affecting primarily adolescents and young adults. Patients with secondary EwS are excluded from risk stratification in several studies and therefore do not benefit from new therapies. More knowledge about patients with EwS as secondary malignant neoplasms (SMN) is needed to identify at-risk patients and adapt follow-up strategies. Epidemiology, clinical characteristics, and survival analyses of EwS as SMN were analyzed in 3844 patients treated in the last three consecutive international EwS trials, EICESS 92, Euro-E.W.I.N.G. 99, and EWING 2008. Forty-two cases of EwS as SMN (approximately 1.1% of all patients) were reported, preceded by a heterogeneous group of malignancies, mainly acute lymphoblastic leukemias (n = 7) and lymphomas (n = 7). Three cases of EwS as SMN occurred in the presumed radiation field of the primary tumor. The median age at diagnosis of EwS as SMN was 19.4 years (range, 5.9-72) compared with 10.8 years (range, 0.9-51.2) for primary EwS. The median interval between first malignancy and EwS diagnosis was 7.4 years. The 3-year overall survival (OS)/event-free survival (EFS) was 0.69 (SE = 0.09)/0.53 (SE = 0.10) for localized patients and 0.36 (SE = 0.13)/0.29 (SE = 0.12) for metastatic patients (OS: p = 0.02; EFS: p = 0.03). Survival in patients with EwS as SMN did not differ between hematologic or solid primary malignancies. EwS as SMN is rare; however, survival is similar to that of primary EwS, and its risk-adjusted treatment should be curative, especially in localized patients.

Extraosseous Ewing Sarcoma in Children: A Systematic Review and Meta-Analysis of Clinicodemographic Characteristics

Background: We conducted this systematic review to provide comprehensive evidence on the prevalence, clinical features and outcomes of young extraosseous Ewing sarcoma (EES) cases. Methods: PubMed, Scopus, Web of Science, and Google Scholar were searched for articles reporting the occurrence of EES among children and adolescents (<21 years). The primary outcome included the rate of occurrence of EES among children and adolescents, while the secondary outcomes included the descriptive analyses of the demographic characteristics, tumor characteristics, and clinical outcomes of the affected cases. The data are reported as the effect size (ES) and its corresponding 95% confidence interval (CI). Results: A total of 29 studies were included. Twenty-four reported instances of childhood disease among all the EES cases [ES = 30%; 95%CI: 29−31%], while five studies reported extraosseous cases among the pediatric EES cases [ES = 22%; 95%CI: 13−31%]. The thorax is the most common location of childhood EES [33%; 95%CI: 20−46%] followed by the extremities [31%; 95%CI: 22−40%]. Concurrent chemotherapy and radiotherapy [57%; 95%CI: 25−84%] was the most commonly implemented management protocol in the pediatric EES cases. The rate of no evidence of disease and 5-year overall survival was 69% for both outcomes. Mortality occurred in 29% of cases, while recurrence and secondary metastasis occurred in 35% and 16% of cases, respectively. Conclusions: Our findings provide insight into the clinical features and outcomes of EES among children and adolescents.

The importance of fusion protein activity in Ewing sarcoma and the cell intrinsic and extrinsic factors that regulate it: A review

Accumulating evidence shows that despite clonal origins tumors eventually become complex communities comprised of phenotypically distinct cell subpopulations. This heterogeneity arises from both tumor cell intrinsic programs and signals from spatially and temporally dynamic microenvironments. While pediatric cancers usually lack the mutational burden of adult cancers, they still exhibit high levels of cellular heterogeneity that are largely mediated by epigenetic mechanisms. Ewing sarcomas are aggressive bone and soft tissue malignancies with peak incidence in adolescence and the prognosis for patients with relapsed and metastatic disease is dismal. Ewing sarcomas are driven by a single pathognomonic fusion between a FET protein and an ETS family transcription factor, the most common of which is EWS::FLI1. Despite sharing a single driver mutation, Ewing sarcoma cells demonstrate a high degree of transcriptional heterogeneity both between and within tumors. Recent studies have identified differential fusion protein activity as a key source of this heterogeneity which leads to profoundly different cellular phenotypes. Paradoxically, increased invasive and metastatic potential is associated with lower EWS::FLI1 activity. Here, we review what is currently understood about EWS::FLI1 activity, the cell autonomous and tumor microenvironmental factors that regulate it, and the downstream consequences of these activity states on tumor progression. We specifically highlight how transcription factor regulation, signaling pathway modulation, and the extracellular matrix intersect to create a complex network of tumor cell phenotypes. We propose that elucidation of the mechanisms by which these essential elements interact will enable the development of novel therapeutic approaches that are designed to target this complexity and ultimately improve patient outcomes.

Primary Ewing sarcoma of the liver: Diagnosis, management, and prognosis: A case report and literature review

Ewing's sarcoma tumors (ES) are a rare entity exceptionally localized on the liver. We report a case of an ES of the liver in a 26-year-old man who presented with abdominal pain. The diagnosis was confirmed with a histopathological examination of the left hepatectomy specimen and adjuvant chemotherapy was received.

Case report: Primary intracranial EWs/PNET in adults: Clinical experience and literature review

Introduction

Adult primary intracranial Ewing sarcomas (EWs)/primitive neuroectodermal tumors (PNETs) are extremely rare, with only 30 patients published before us. The imaging features and treatment strategies of primary intracranial EWs/PNETs are unclear due to its rarity. The aim of this study was to investigate the clinical features, imaging findings, treatment, survival analysis, and prognosis of adult EWs/PNETs, and a systematic review was conducted based on the patient we treated and published literature.

Case description

A 19-year-old male patient suffered from head pain due to an accidental fall on a motorcycle that occurred more than 10 days before going to the hospital, and underwent computed tomography (CT) examination; it was found that the left temporo-occipital fossa was occupied. Magnetic resonance imaging (MRI) was recommended to understand the nature of the lesion, and the result showed that it has a high probability of being a meningioma. He underwent surgical removal of the mass under general anesthesia, and surprisingly, postoperative pathology revealed EWs/PNET. The disease has a high degree of malignancy, and the patient developed multiple metastases throughout the body 5 years after surgery.

Conclusion

Primary intracranial EWs/PNETs in adult patients are rare, of which imaging findings should be considered as one of the differential diagnoses of meningioma, hemangiopericytoma, and malignant triton tumor. Larger solid-cystic masses with septum-like enhancement may be relatively specific imaging findings of intracranial EWs/PNETs. The prognosis of primary adult intracranial EWs/PNETs is poor. Radical tumor resection combined with radiotherapy and chemotherapy is currently the main and possibly the most effective treatment method.

PROPROTEIN CONVERTASE 1/3 DEFICIENCY WITH PELVIC EWING SARCOMA

Proprotein convertase 1/3 (PC 1/3) deficiency is a rare, autosomal recessive disorder caused by mutations in the PCSK1 gene. The disease is characterized by early-onset chronic diarrhea/malabsorption, followed by severe obesity and hormonal deficiencies such as hypocortisolism, hypothyroidism, diabetes insipidus, hypogonadism, growth deficiency, and diabetes mellitus. Ewing's sarcoma is a rare tumor, usually of small dimensions of neuroectodermal origin that is difficult to distinguish pathologically from a primitive neuroectodermal tumor. A 22-year-old female patient with PC 1/3 deficiency was admitted to our clinic with recurrent urinary tract infections. Magnetic resonance imaging (MRI) revealed an 11x12 cm pelvic mass displacing the uterus. A core-needle biopsy was performed on the pelvic mass. As a result of the pathological evaluation, ıt was diagnosed with pelvic Ewing's sarcoma. The patient was started on the VAC-IE chemotherapy protocol. We report a case of pelvic Ewing's sarcoma in a patient with PC 1/3 deficiency. Further research is needed to assess malignancy risk in metabolic disorders including very rare disorders like PC 1/3 deficiency.

Management of pelvic sarcoma

Pelvic sarcomas are a rare and heterogenous group of tumors divided into two groups: soft tissue sarcomas and bone sarcomas. Soft tissue sarcomas of the pelvis include most commonly liposarcoma, leiomyosarcoma, gastrointestinal stromal tumors, malignant peripheral nerve sheath tumors, and solitary fibrous tumors. Bone sarcomas of the pelvis most commonly include osteosarcoma and chondrosarcoma. Multidisciplinary treatment at a center experienced in the treatment of sarcoma is essential. Management is dictated by histologic type and grade. Surgical resection with wide margins is the cornerstone of treatment for pelvic sarcomas, although this is often challenging due to anatomic constraints of the pelvis. Multimodal treatment is critical due to the high risk of local recurrence in the pelvis.

Intramedullary, periosteal, and extraskeletal Ewing sarcomas: retrospective study of a series of 126 cases in a reference center

OBJECTIVE

To evaluate the proportion of extraskeletal, periosteal, and intramedullary Ewing sarcomas among musculoskeletal Ewing sarcomas.

MATERIAL AND METHOD

Our single-center retrospective study included patients with musculoskeletal Ewing sarcoma diagnosed between 2005 and 2019 in our pathology center (cases from our adult bone tumor referral center and adult and pediatric cases referred for review). Recurrences, metastases, and visceral Ewing sarcomas were excluded. Intramedullary Ewing sarcomas were defined by involvement of the medullary cavity. Periosteal cases were defined by involvement of the subperiosteal area without extension to the medullary cavity. Extraskeletal cases were defined by the absence of involvement of the bone tissue and the subperiosteal area.

RESULTS

Our series included 126 patients with musculoskeletal Ewing sarcoma, including 118 skeletal Ewing sarcomas (93.7%) and 8 extraskeletal Ewing sarcomas (6.3%). Of the 118 skeletal Ewing sarcomas 112 were intramedullary (88.9%) and 6 were periosteal (4.8%). Extraskeletal Ewing sarcomas were more common in women and in patients older than 40 (p < 0.05).

DISCUSSION

The 6.3% proportion of extraskeletal Ewing sarcoma is lower than the median of 30% estimated from the literature. This difference could be explained by an overestimation of extraskeletal Ewing sarcomas of the chest wall (Askin tumors), an underestimation of periosteal cases confused with extraskeletal cases, and the presence of "Ewing-like" soft tissue sarcomas in previous series. Because of its prognostic and therapeutic impact, the distinction of morphologic subtypes requires the cooperation of experienced radiologists and pathologists.

Extraskeletal Ewing Sarcoma from Head to Toe: Multimodality Imaging Review

Extraskeletal Ewing sarcoma (EES) is a rare subtype in the Ewing sarcoma family of tumors (ESFT), which also includes Ewing sarcoma of bone (ESB) and, more recently, primitive neuroectodermal tumors. Although these tumors often have different manifestations, they are grouped on the basis of common genetic translocation and diagnosis from specific molecular and immunohistochemical features. While the large majority of ESFT cases occur in children and in bones, approximately 25% originate outside the skeleton as EES. Importantly, in the adult population these extraskeletal tumors are more common than ESB. Imaging findings of EES tumors are generally nonspecific, with some variation based on location and the tissues involved. A large tumor with central necrosis that does not cross the midline is typical. Despite often nonspecific findings, imaging plays an important role in the evaluation and management of ESFT, with MRI frequently the preferred imaging modality for primary tumor assessment and local staging. Chest CT and fluorine 18 fluorodeoxyglucose PET/CT are most sensitive for detecting lung and other distant or nodal metastases. Management often involves chemotherapy with local surgical excision, when possible. A multidisciplinary treatment approach should be used given the propensity for large tumor size and local invasion, which can make resection difficult. Despite limited data, outcomes are similar to those of other ESFT cases, with 5-year survival exceeding 80%. However, with metastatic disease, the long-term prognosis is poor. ^©RSNA, 2022.

Extraosseous Ewing sarcoma in children and adolescents: A retrospective series from a referral pediatric oncology center

BACKGROUND

Extraosseous Ewing sarcoma is a rare entity and less is known about its clinical behavior and optimal treatment than for its counterpart in bone. This study is a retrospective analysis on a cohort of patients <21 years treated according to a "soft tissue sarcoma approach."

METHODS

The "extraosseous" origin of the tumor was established on radiological findings, based on the lack of any bone involvement. Patients were treated using a multimodality approach including surgery, radiotherapy, and chemotherapy. All patients received chemotherapy with alkylating agents and anthracyclines for 25 weeks (nine courses). Radiotherapy (45-54.8 Gy) was required for all cases except those who had an initial R0 resection of tumors smaller than 5 cm.

RESULTS

Fifty-seven patients (age 2-20 years, median 14) were treated from 1990 to 2020. Ten-year event-free survival (EFS) and overall survival (OS) were 77.5% and 85.5% in patients with localized disease, and 11.1% and 29.6% in those with metastatic disease (p < .001) (follow-up 5-349 months, median 107 months). In patients with localized disease, the most recent IVADo-IVE regimen achieved excellent survivals, that is, 10-year EFS 95.5%.

CONCLUSIONS

Our study showed that satisfactory results were achieved in patients with localized extraosseous Ewing sarcoma treated with a tailored approach derived from soft tissue sarcoma protocols, which was less intensive and shorter as compared to the standards utilized for the management of bone Ewing sarcoma. Our study suggests that the extraskeletal site might be considered as a variable to stratify patients and modulate treatment intensity accordingly in Ewing sarcoma protocol.

Challenges in diagnosing an extraosseous Ewing sarcoma: A case report

INTRODUCTION

Ewing sarcoma is a highly malignant and rare tumour of bones and soft tissue. It may occur at any age, but it is more common in children and teenagers.

CASE REPORT

We report a case of a 56-year-old woman with EES involving the right iliac fossa. Previous abdominal trauma with retroperitoneal hematoma, nonspecific symptoms and unusual age for EES have caused diagnostics difficulties. The first histopathological examination misdiagnosed tumour to be a GIST, and just after the second surgery the accurate diagnosis of EES was made.

CONCLUSIONS

The diagnosis of ES sometimes is complicated and delayed. Prompt detailed examination and imaging studies should be performed to people with long lasting pain without trauma and other nonspecific symptoms, especially followed by a palpable mass. The treatment of EES is multimodal.

Characterization of cannabinoid receptors expressed in Ewing sarcoma TC-71 and A-673 cells as potential targets for anti-cancer drug development

AIMS

Characterizing cannabinoid receptors (CBRs) expressed in Ewing sarcoma (EWS) cell lines as potential targets for anti-cancer drug development.

MAIN METHODS

CBR affinity and function were examined by competitive binding and G-protein activation, respectively. Cannabinoid-mediated cytotoxicity and cell viability were evaluated by LDH, and trypan blue assays, respectively.

KEY FINDINGS

qRT-PCR detected CB1 (CB1R) and CB2 receptor (CB2R) mRNA in TC-71 cells. However, binding screens revealed that CBRs expressed exhibit atypical properties relative to canonical receptors, because specific binding in TC-71 could only be demonstrated by the established non-selective CB1/CB2R radioligand [³H]WIN-55,212-2, but not CB1/CB2R radioligand [³H]CP-55,940. Homologous receptor binding demonstrated that [³H]WIN-55,212-2 binds to a single site with nanomolar affinity, expressed at high density. Further support for non-canonical CBRs expression is provided by subsequent binding screens, revealing that only 9 out of 28 well-characterized cannabinoids with high affinity for canonical CB1 and/or CB2Rs were able to displace [³H]WIN-55,212-2, whereas two ligands enhanced [³H]WIN-55,212-2 binding. Five cannabinoids producing the greatest [³H]WIN-55,212-2 displacement exhibited high nanomolar affinity (K_i) for expressed receptors. G-protein modulation and adenylyl cyclase assays further indicate that these CBRs exhibit distinct signaling/functional profiles compared to canonical CBRs. Importantly, cannabinoids with the highest affinity for non-canonical CBRs reduced TC-71 viability and induced cytotoxicity in a time-dependent manner. Studies in a second EWS cell line (A-673) showed similar atypical binding properties of expressed CBRs, and cannabinoid treatment produced cytotoxicity.

SIGNIFICANCE

Cannabinoids induce cytotoxicity in EWS cell lines via non-canonical CBRs, which might be a potential therapeutic target to treat EWS.

Extraskeletal Ewing sarcoma in children, adolescents, and young adults. An analysis of three prospective studies of the Cooperative Weichteilsarkomstudiengruppe (CWS)

BACKGROUND

We have analyzed the outcome of patients with localized extraskeletal Ewing sarcoma (EES) treated in three consecutive Cooperative Weichteilsarkomstudiengruppe (CWS) soft tissue sarcoma (STS) studies: CWS-91, CWS-96, and CWS-2002P.

METHODS

Patients were treated in CWS-91 with four- (vincristine, dactinomycin, doxorubicin, and ifosfamide [VAIA] or cyclophosphamide [VACA II]) or five-drug (+etoposide [EVAIA]) cycles, in CWS-96 they were randomly assigned to receive VAIA or CEVAIE (+carboplatin and etoposide), and in CWS-2002P with VAIA III plus optional maintenance therapy (MT) with cyclophosphamide and vinblastine. Local therapy consisted of resection and/or radiotherapy (RT).

RESULTS

Two hundred forty-three patients fulfilled the eligibility criteria. The 5-year event-free survival (EFS) and overall survival (OS) were 63% (95% confidence interval [CI] 57-69) and 73% (95% CI 67-79), respectively. The 5-year EFS by study was 64% (95% CI 54-74) in CWS-91, 57% (95% CI 48-66) in CWS-96, and 79% (95% CI 67-91) in CWS-2002P (n.s.). The 5-year OS was 72% (95% CI 62-82) in CWS-91, 70% (95% CI 61-79) in CWS-96, and 86% (95% CI 76-96) in CWS-2002P (n.s.). In CWS-96, 5-year EFS and OS in the VAIA arm versus the CEVAIE were 65% (95% CI 52-81) versus 55% (95% CI 39-76) log-rank p = .13, and 85% (95% CI 75-96) versus 61% (95% CI 45-82), log-rank p = .09.

CONCLUSION

Our analysis provides interesting information on the treatment and specificities of EES, which can be useful for a better understanding of this rare entity and should be considered in the development of future clinical trials for Ewing sarcoma defined as FET-ETS fusion positive tumors.

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 ± 2.6%, 55.2 ± 2.9% and 64.3 ± 2.6%, 54.1 ± 2.8%, 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.

Management of Abdominal Ewing's Sarcoma: A Single Institute Experience

Ewing’s sarcoma (ES)/primitive neuroectodermal tumors (PNETs) are a rare group of tumors commonly arising from bones, uncommonly from soft tissues, and rarely from abdomen. The aim of the study was to analyze the outcome (recurrence-free survival[RFS]), patient characteristics, role of FDG-PET (fluorodeoxyglucose positron emission tomography) computerized scan, chemotherapy and radiation, and prognostic factors. We retrospectively studied patients diagnosed with abdominal ES/PNET and treated surgically between June 2005 and November 2019. Ten patients were included in the study, with a median age of 36.5 years (19–46 years). The median follow-up was 25 months (3–178 months). The site of origin was the retroperitoneum, small bowel, and abdominal wall in six, two, and two patients, respectively. 70% of patients were treated with induction chemotherapy. R0 resection was achieved in 90% of patients. With chemotherapy, there was significant reduction in tumor size (p = 0.034) with non-significant reduction in SUV max (p = 0.31). The 1- and 2-year RFS were 88.90% and 76.20%, respectively. Pathological peritoneal metastasis and ability to achieve R0 resection were prognostic factors affecting RFS. These patients must be offered multimodality treatment. Induction chemotherapy significantly reduces the tumor size. Pathological peritoneal metastasis and ability to achieving R0 resection significantly affect survival.

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.

Ewing Sarcoma of the Craniofacial Bones: A Qualitative Systematic Review

OBJECTIVES

To conduct a systematic review on the demographics, characteristics, management, treatment, complications, and outcomes of Ewing sarcomas in the craniofacial bones.

DATA SOURCES

Using Cochrane Library, EmBase, and PubMed, the authors identified 71 studies to be included.

REVIEW METHODS

The Cochrane Library, EmBase, and PubMed databases were used to identify literature relating to Ewing sarcomas in the craniofacial bone to conduct a systematic review. Patient demographics, clinical characteristics, and treatment strategies were extracted.

RESULTS

Seventy-one studies encompassing 102 patients were identified. The most common craniofacial locations involved were the frontal bone (16.7%, n = 17), nasal cavity (16.7%, n = 17), and temporal bone (14.7%, n = 15). Stratified by location, the most common presenting symptoms were frontal bone (palpable mass, n = 8, 47.1%), nasal cavities (epistaxis, n = 9, 52.9%), and temporal bones (headache, n = 5, 33.3%). The 3 most commonly used treatment strategies were a combination of surgical intervention/radiotherapy/chemotherapy (n = 43, 43%), a combination of radiotherapy/chemotherapy (n = 18, 18%), and a combination of surgical intervention/chemotherapy (n = 15, 15%). Patients who received a combination of surgical intervention/radiotherapy/chemotherapy experienced local recurrence rate of 16.6%. However, other combinations of therapies such as surgical intervention/chemotherapy and radiotherapy/chemotherapy had a lower local recurrence rate but were limited by small sample size. Most patients (79.0%) were disease free without evidence of recurrence.

CONCLUSION

Ewing Sarcoma of the craniofacial bones has a good prognosis when treated appropriately. Given that our study was limited by retrospective data, we advise clinicians to use the findings of this article with their own clinical judgment to determine which treatment strategy they should pursue.