Extraskeletal Ewing's Sarcoma Research Articles

Posterior mediastinal Ewing sarcoma with multiple metastases on FDG PET/CT: a rare entity

BackgroundEwing sarcoma and peripheral primary neuroendocrine tumors are aggressive neoplasms which consist of small, round, blue cells of neuroectodermal origin. They usually arise from the skeleton and consist of genetic mutations EWSR1 in chromosome 22 and FL1 gene on chromosome 11. Extraskeletal Ewing sarcomas (EES) are rare entities with most common sites of EES being extremities, head and neck region and retroperitoneum. Posterior mediastinal Ewing sarcoma is rare. For its evaluation, 18F-fluorodeoxyglucose positron emission tomography (18F FDG PET/CT) plays significant role in staging, management planning and prognostication.Case presentationWe describe a rare case of EES of posterior mediastinum in a 20-year-old boy who presented with signs of upper motor neuron lesion below D10 level. Contrast-enhanced magnetic resonance imaging (CEMRI) showed a heterogeneously enhancing posterior mediastinal mass in pre- and paravertebral region with intraspinal extension in D2-D4 levels. Fluorodeoxyglucose PET/CT showed a metabolically active mass occupying the superior, middle and posterior mediastinum on the left, displacing the trachea and esophagus toward the right side and causing complete collapse of the left lung. Posteriorly the mass was seen destroying the D2-D5 vertebrae with intraspinal extension at D2-D4 level. Metabolically active metastatic disease was seen in pleura, skull, D12 vertebra, right iliac bone and bilateral proximal femorae. Biopsy obtained from lung and adjacent pleura showed features of a round cell tumor positive for NKX 2.2, weak positive for FLI 1 and negative for PAN CK, LCA, Vimentin and TLE-1, suggestive of Ewing sarcoma. Based on these investigations, a diagnosis of EES of posterior mediastinum was made.ConclusionExtraskeletal Ewing sarcoma of posterior mediastinum is a rare and aggressive entity. Management of metastatic EES comprises radiotherapy and systemic chemotherapy which reduces tumor burden and micrometastasis. However, response to treatment in metastatic EES is poorer than in localized disease with overall 5-year survival rates of less than 30%. Fluorodeoxyglucose PET/CT can be a useful tool to accurately detect the extent of local disease in the presence of atelectasic lung for radiotherapy planning as well as evaluating response to therapy.

Is Bone Marrow Aspiration and Biopsy of Clinical Importance in the Initial Staging of Extraskeletal Ewing Sarcoma?

Extraskeletal Ewing sarcoma are rare tumors within the Ewing sarcoma family. Initial staging studies for extraskeletal Ewing sarcoma historically have included imaging and bone marrow aspiration and biopsy (BMAB). However, recent studies on Ewing sarcoma of bone have questioned the utility of BMAB in the initial staging of patients, but no studies of which we are aware have evaluated the role of BMAB in extraskeletal Ewing sarcoma. We suspected that BMAB was of low diagnostic yield in patients with extraskeletal Ewing sarcoma and exposed patients to potential morbidity without an impact on their clinical course. Is BMAB a useful test in the staging of extraskeletal Ewing sarcoma? Between January 1996 and December 2021, our institution evaluated 109 patients with a listed diagnosis of extraskeletal Ewing sarcoma. Those patients were retrospectively reviewed for this study. Of those, we considered patients with biopsy-confirmed diagnosis of extraskeletal Ewing sarcoma. Biopsy was performed based on institutional protocols, with all diagnoses assigned by a board-certified pathologist. Based on that criteria, 96% (105 of 109) were eligible. An additional 18% (20 of 109) were excluded because records of their initial diagnostic and staging workup were not available. This left 78% (85 of 109) for analysis. Of those, 52% (44 of 85) were male. The average age was 32 ± 16 years. Primary tumor locations included extremities in 26% (22 of 85), paraspinal in 20% (17 of 85), chest in 19% (16 of 85), retroperitoneum in 13% (11 of 85), intraabdominal in 12% (10 of 85), intrapelvic in 7% (6 of 85), and head or neck in 4% (3 of 85). Initial diagnostic and staging information, including the use of PET-CT, bone scan, CT chest, and BMAB, was collected. Metastatic disease at the time of presentation or during follow-up was noted. The utility of BMAB was determined by the rate of positive tests in those undergoing BMAB during the initial staging process. Descriptive statistical analysis was sufficient to address the study question, and therefore no comparative statistics were performed. BMAB was obtained during the initial staging process in 64% (54 of 85) of patients. This BMAB was negative in all 54 patients, including those with known metastatic disease. Diagnosing metastatic disease in extraskeletal Ewing sarcoma is important as the presence of metastases at diagnosis adversely affects prognosis. The routine use of BMAB in the staging process of extraskeletal Ewing sarcoma is of low diagnostic yield. BMAB is unlikely to diagnose metastatic involvement even in patients with known metastases to bone. We do not have enough data to suggest whether other modalities, such as PET-CT, might be more useful. Similar studies should be pursued to determine the utility of the remainder of staging modalities in patients with extraskeletal Ewing sarcoma to elucidate the most efficient and effective staging protocol. Level III, diagnostic study.

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

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. This retrospective analysis was conducted among patients aged more than 15 years with histologically proven EWS. 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. 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.

A Teenage Girl with Large Lung Mass

Extraskeletal Ewing Sarcoma is rarely reported. A fifteen-year-old girl presented with the right-sided pleuritic chest pain, shortness of breath, and productive cough with whitish sputum associated with poor oral intake. She subsequently underwent contrast-enhanced Computerized Tomography thorax, which showed lobulated heterogenous hypodensity occupying the entrance of the right superior pulmonary vein, extending to the left atrium.

Retroperitoneal Extraskeletal Ewing’s Sarcoma in Adult

Ewing’s sarcoma is a highly malignant tumour of osseous or non-osseous origin, typically seen in the paediatric and adolescent age group. However, extraskeletal Ewing’s sarcoma is an uncommon tumour. It could arise from the soft tissue in the paravertebral area, chest wall, head and neck, and retroperitoneum. Retroperitoneal extraosseous Ewing’s sarcoma is even rarer, with only a few reported cases in the literature. We describe the radiologic findings of this rare retroperitoneal extraskeletal Ewing sarcoma manifested in an adult patient. Our patient is a 32-year-old gentleman who presented with abdominal pain and constitutional symptoms for two months. Imaging shows a retroperitoneal tumour with local infiltration. It was confirmed via histopathological analysis as retroperitoneal Ewing’s sarcoma. We discussed the diagnostic strategy as well as the literature review of this rare disease.

Sino-nasal and pharyngeal mass- Immunohistochemistry cuts the gordian knot

Sinonasal and pharyngeal mass lesion of Extraskeletal Ewing sarcomas (EEWSs) are extremely rare. Herein we present a case of EEWSs of ethmoid sinus extending into nasal and pharyngeal spaces mimicking as angiofibroma clinically. Histopathological examination in conjunction with immunohistochemistry puzzled out the diagnostic dilemma.

Sarcoma de Ewing extraesquelético: relato de um caso raro e exuberante simulando lipoma

Extraskeletal Ewing sarcoma (EES) is a rare tumor that affects men between 10-20 years old and represents 25% of Ewing sarcomas. We report a case due to the previous diagnosis of a fast-growing lipoma to highlight the importance of histopathological diagnosis. A 14-year-old boy presented 10x10 cm tumor in the right shoulder for a year with ultrasonography suggesting lipoma. The lesion was excised and EES was confirmed by immunohistochemical analysis. EES diagnosis in young people is challenging compared to subcutaneous tumors, and histopathology is essential. The rapid progression of the tumor and high metastatic rates highlight the significance of early treatment.

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

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. 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. 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 diedof 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 alsoassociated with poorer OS. On multivariate analysis, trunkal location and margin-positive resections retained statistical significance for adverse EFS. 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.

Categorizing Malignant Small Round Cell Tumors in Aspiration Cytology: An Institutional Experience.

The study aims to categorize malignant small round cell tumors (MSRCTs) originating in various sites of the body with the objective of utilization of cytomorphological features and ancillary techniques. It is a cross-sectional study conducted over a time span of 3 years (2017-2020). 33 cases of tumors with round cell morphology were evaluated by fine needle aspiration cytology (FNAC). The application of cell block preparation supported by immunohistochemistry aided in the categorization of 23 cases with definite diagnosis and the rest were reported as MSRCTs. Among the categorized 23/33 cases, the most common diagnosis was Ewing's sarcoma (7/23) followed by 6 cases of lymphoma. There were 2 cases each of rhabdomyosarcoma and Langerhans cell histiocytosis (LCH) and 1 case each of neuroblastoma, desmoplastic small round cell tumor (DSRCT), myeloid sarcoma, neuroendocrine tumor of pancreas, plasmacytoma, and small cell carcinoma. Histopathology confirmation was available in 24/33 cases. Among the categorized tumors (23/33), biopsy correlation was available in 19 cases, of which concordant result was seen in 17 cases (89.47%), which were 6 cases of lymphoma, 5 cases of Ewing's sarcoma (EWS), 2 of rhabdomyosarcoma, and 1 each of neuroblastoma, small cell carcinoma, DSRCT, and LCH. Discordant result was seen in one case of rhabdomyosarcoma and a case of synovial sarcoma reported as extraskeletal EWS in cytology. Out of the uncategorized cases reported as MSRTCs, histopathology was available in 5 cases which were diagnosed as rhabdomyosarcoma (1 cases), lymphoma (1 case), amelanotic melanoma (1 case), and extraskeletal EWS (2 cases). Categorization of MSRCTs should be done to implement appropriate therapeutic protocol. FNAC provides a rapid diagnosis contributing immensely for the timely management of the patient. Detailed cytomorphological evaluation serves as a guide for further evaluation by ancillary techniques leading to definitive diagnosis.

436P Oncologic outcomes in patients with extraskeletal Ewing’s sarcoma (EES): A tertiary care centre experience

Extraskeletal Ewing’s sarcoma (EES) is a rare entity, accounting for 15% of all Ewing’s sarcomas. Multimodality management with aggressive surgical resection, adjuvant chemotherapy, and radiotherapy are cornerstones for good oncological outcomes. We analyzed homogenously treated patients at our Centre and evaluated the oncological outcomes.

18F-FDG PET/CT of Primary Extraskeletal Ewing Sarcoma of the Prostate.

Prostate Ewing sarcoma is rare. We report the 18F-FDG PET/CT finding of a 16-year-old adolescent boy who presented with dysuria and was confirmed to be extraskeletal Ewing sarcoma of the prostate by histopathologic findings.

Ewing's Sarcoma of the Gastrointestinal Tract—A Case Series

Ewing's sarcoma is a neoplasm of the undifferentiated small round cells, which generally affects the bone and deep soft tissues of children and adolescents. Extraskeletal Ewing's sarcomas are less common than skeletal Ewing's sarcoma with the most common sites being chest wall, retroperitoneal space, lower extremities, paravertebral region, and gluteal region. Primary Ewing's sarcoma of the gastrointestinal tract is rare. The rarity of cases, lack of specific literature, or guidelines for treatment and varying presentations make these cases challenging to diagnose and to treat. In this series, we share our experience from a tertiary cancer care center in South India. By our knowledge, this is the first case series in literature sharing the experience from a single center in treating four cases of gastrointestinal Ewing's sarcoma.

Two-Phase Deep Learning Algorithm for Detection and Differentiation of Ewing Sarcoma and Acute Osteomyelitis in Paediatric Radiographs.

Ewing sarcoma is a highly malignant tumour predominantly found in children. The radiological signs of this malignancy can be mistaken for acute osteomyelitis. These entities require profoundly different treatments and result in completely different prognoses. The purpose of this study was to develop an artificial intelligence algorithm, which can determine imaging features in a common radiograph to distinguish osteomyelitis from Ewing sarcoma. A total of 182 radiographs from our Sarcoma Centre (118 healthy, 44 Ewing, 20 osteomyelitis) from 58 different paediatric (≤18 years) patients were collected. All localisations were taken into consideration. Cases of acute, acute on chronic osteomyelitis and intraosseous Ewing sarcoma were included. Chronic osteomyelitis, extra-skeletal Ewing sarcoma, malignant small cell tumour and soft tissue-based primitive neuroectodermal tumours were excluded. The algorithm development was split into two phases and two different classifiers were built and combined with a Transfer Learning approach to cope with the very limited amount of data. In phase 1, pathological findings were differentiated from healthy findings. In phase 2, osteomyelitis was distinguished from Ewing sarcoma. Data augmentation and median frequency balancing were implemented. A data split of 70%, 15%, 15% for training, validation and hold-out testing was applied, respectively. The algorithm achieved an accuracy of 94.4% on validation and 90.6% on test data in phase 1. In phase 2, an accuracy of 90.3% on validation and 86.7% on test data was achieved. Grad-CAM results revealed regions, which were significant for the algorithms decision making. Our AI algorithm can become a valuable support for any physician involved in treating musculoskeletal lesions to support the diagnostic process of detection and differentiation of osteomyelitis from Ewing sarcoma. Through a Transfer Learning approach, the algorithm was able to cope with very limited data. However, a systematic and structured data acquisition is necessary to further develop the algorithm and increase results to clinical relevance.

Cushing’s disease secondary to a pancreatic Ewing Sarcoma in an 18-month-old child: a case report

Extraskeletal paediatric Ewing Sarcoma with resultant Cushing’s syndrome due to ectopic ACTH (adrenocorticotropic hormone) production is a very rare presentation with a poor prognostic outlook. This is the first pancreatic case ever reported.

Ewing sarcoma: A pictorial review of typical and atypical locations with reference to the updated 2020 WHO classification system.

Ewing sarcoma (ES) is a small round cell sarcoma which usually occurs in the paediatric and young adult age groups. This pictorial review briefly discusses and presents the typical skeletal and extraskeletal locations which ES is encountered, including the metadiaphysis of long bones, pelvis, chest wall and paravertebral regions. Five cases of ES in atypical locations are then presented along with an observation of demographic differences between skeletal and extraskeletal ES. These cases include ES arising from the metatarsal, scapula, breast, intracranial soft tissue and the paranasal sinuses. Presenting symptoms, treatment approach and prognosis are highly variable depending on the location; and multimodal imaging is centrepiece in the management process. Management usually includes any combination of chemotherapy, radiotherapy and surgery. The WHO classification system was updated in 2020 to include some of the rare genetic subtypes of ES. One such case of the BCOR subtype is demonstrated in this review and occurs in an atypical location. Whether these subtypes have distinct radiological features or a propensity to occur in atypical locations is an area for further research.

Esophageal extraskeletal neoplasm Ewing's sarcoma: Case report.

Introduction and importanceEwing sarcomas are a group of small round cell tumors that occur predominantly in the long bones as well as in extraosseous locations such as the extremities, trunk, and retroperitoneum (Gier, 1997) [2]. Extraosseous Ewing sarcoma (EES) is a type of small round cell tumor that occurs in soft tissues. I rare cases, EES occurs in the esophagus (Maesawa et al., 2002; Johnson et al., 2010) [1,3]. Ewing's sarcoma is a rare and highly aggressive cancer most frequently arising in people under 20 years of age. We report an uncommon case of primary paraesophageal Ewing's sarcoma in a 25-year-old female.Case presentationA 26 years old Asian female referred primarily for surgical treatment due to esophageal cancer detected on her diagnostic investigations and revealed a primary tumor located near the gastroesophageal junction. Based on the results of diagnostic investigations which confirmed the possibility of the tumor Ewing sarcoma of esophagus, which was biopsy and immune histochemical stain proven the patient was qualified for surgical treatment. She underwent Mckewon esophagectomy on October 2021 for Ewing sarcoma of esophagus. She was first followed with neoadjuvant intravenous chemotherapy, after taking three cycles of neoadjuvant chemo showed good response in CT scan the patient underwent Mckewon esophagectomy, post op recovery was smooth she underwent 2 cycles of adjuvant chemotherapy after four months of surgery. Her followup visit was uneventful.Clinical discussionEwing's sarcoma is the second most frequent primary malignant bone cancer, after osteosarcoma. It was first described by James Ewing in 1921, as an undifferentiated tumor developing in the diaphysis of the ulna of a young female patient (Ushigome et al., 2002) [6]. Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET), previously thought to be separate tumors, is now treated as the same tumor; both have similar immunohistochemical characteristics and chromosomal translocation (Maesawa et al., 2002) [1]. They are malignant tumors composed of undifferentiated small round cells, usually affecting children, adolescents, and young adults (Kondo et al., 2005) [7]. Generally ES/PNET affects the bones and deep soft tissues (Soulard et al., 2005) [8], although other organs such as the pancreas, small bowel, esophagus, kidneys, prostate, ovaries, vagina and rectovaginal septum have been reported; this is termed as extraskeletal ES/PNET (Bloom et al., 1995) [9]. To the best of our knowledge, only 5 cases of gastric ES/PNET have been reported in the English language literature.Extraskeletal Ewing's sarcoma is a very rare disease, accounting for 6 %–47 % of all cases of Ewing's sarcoma. It is mainly diagnosed in the trunk, extremities, retroperitoneum, and head and neck region. Patients with extraosseous Ewing's sarcoma are more likely to be older, female, and not of Caucasian origin. An extraskeletal origin of the disease is correlated to poor prognosis (Siegel et al., 1988; Granowetter and West, 1997; Ushigome et al., 2002) [[4], [5], [6]]. We present an uncommon case of extraskeletal Ewing's sarcoma, and discuss its rare presentation and evolution. To our knowledge, this is the first reported case of paraesophageal primary Ewing's sarcoma and primitive neuroectodermal tumor.Adenocarcinoma and squamous cell carcinoma account for the vast majority of esophageal malignancies. Other malignancies known to occur in the esophagus include melanoma, sarcoma, and lymphoma. Among the sarcomas, carcinosarcoma is the commonest with both carcinomatous and sarcomatous elements followed by leiomyosarcoma of mesenchymal origin. Other sarcomas reported in the literature are liposarcoma, synovial sarcoma, myxofibrosarcoma, Ewing's sarcoma, granulocytic sarcoma, histiocytic sarcoma, schwannoma rhabdomyosarcoma, and epithelioid sarcoma.ConclusionEwing sarcoma is a rare entity among all esophageal malignancies. It presents as an exophytic mass, and in this case, it has presented as a mass occluding the lumen of esophagus. Most of these tumors present in locally advanced and disseminated condition, one of the reasons being difficulty and hence delay in diagnosis. In spite of best efforts, a group among them remains to be histologically uncharacterized.

Metronomic oral maintenance chemotherapy in patients with localized high-risk rhabdomyosarcoma (RMS) and RMS-like tumors: A report from a randomized, multicenter, phase III trial CWS-2007HR.

10033 Background: Low dose maintenance therapy as consolidation after multimodal standard therapy has been shown to improve survival in patients with sarcoma. It is however unclear which drugs and how long would be optimal. We investigated whether adding oral maintenance chemotherapy after standard multimodal therapy (ST) in patients with localized RMS and RMS-like sarcoma defined as high and very-high risk (HR and VHR), according to CWS stratification, would improve survival. Methods: Patients (pts) age > 6 months < 21 years, with 1. embryonal RMS N0, incompletely resected, (Group II or III), tumor size > 5cm and/or ≥10 years, in unfavorable primary sites and all N1 (HR RMS Group), 2. alveolar RMS N0/N1 (VHR RMS Group) 3.Unidfferentiated sarcoma (UDS), extraskeletal Ewing sarcoma (EES) and primary non resectable (Group III) synovial sarcoma (SS) (HR RMS-like Group) in complete remission after ST including 9 cycles of ifosfamide, vincristine and actinomycin D +/- doxorubicin, surgery and/or radiotherapy were eligible for randomization to stop treatment (S-arm) or receive maintenance chemotherapy (M-arm) with eight 10-days courses consisting of trofosfamide (2x 75mg/m²/day) and idarubicine (1 x 5mg/m²/day 1,4,7,10) alternating with trofosfamide and etoposide (2x 25mg/m²/day). The study was designed with 80% power and a two-sided alpha level of 5% to detect an increase in 3 yr EFS from 60 to 75%. Randomisation was stratified according to risk groups. To reduce possible imbalances in the number of treatment assignments, a permuted block design was used. The initial calculated sample size was 145 pts in each group (recruitment period six years). Due to the lower than planned recruitement rate, the accrual was extended to 10 years and sample size recalculated to 98 pts in each group. Results: Between 1.7.2009 and 30.6.2019, 441 pts were eligible at diagnosis and 337 at the end of ST. 195 pts were randomized: 99 were assigned to the S-arm and 96 to M-arm. The distribution of the following clinical features:age, gender, tumor size, IRS-Group, T-Status, N-Status, histology and localisation showed no significant difference between the treatment groups. In the intent to treat population, with a median follow up of 4.9 years (IQR 3.0-5.7) in surviving pts, 3yr EFS and OS in M-arm vs S-arm were respectively: EFS 66.2% (95% IC 57.1-76.79) vs 75.0% (95% IC 66.8-84.3) (p 0.07) and OS 81.9% (95% IC 74.2-90.4) vs 84.6 (95% IC 77.5-92.4) (p 0.15). Toxicity grade 3 (no grade 4) in the M-arm was: hematological in 51 %, febrile infection 5%, sensory neuropathy in 1% pts. Conclusions: The addition of maintenance therapy with trofosfamide, etoposide and idarubicine after ST does not improve EFS and OS in patients with high risk RMS and RMS-like sarcomas. Clinical trial information: 2007-0001478-10.

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.

A case report of retroperitoneal Ewing sarcoma requiring adrenalectomy.

Introduction and importanceEwing's sarcoma is a rare entity of malignant in both skeletal and extra-skeletal sites. There are few patients reported as Extra-Skeletal Sarcoma, and fewer reported cases for Extraskeletal Ewing sarcoma involving the retroperitoneal region. Reporting such a rare entity will add to literature in helping the diagnosis and management of such cases.Case presentationWe present a case of 26 year old previously healthy female complaining of a vague abdominal pain and discovered to have retroperitoneal Ewing sarcoma adherent to left adrenal gland.Clinical discussionShe was managed with a combination of neoadjuvant chemotherapy and resection through exploratory laparotomy.ConclusionIn short, Ewing sarcoma should be considered in the differential diagnosis for young patient who is presenting with a retroperitoneal mass.

Primary Extraskeletal Ewing Sarcoma of the Thoracolumbar Epidural Space: Rare Case Report in a Child

Abstract Introduction Ewing sarcomas are a family of tumors that can be of skeletal or extraskeletal origin. We report a rare case of a child with extraskeletal Ewing sarcoma in the thoracolumbar epidural space. Case Report The patient was a 1-year-old female child with sphincter alteration, flaccid paraplegia, and areflexia. A magnetic resonance imaging (MRI) scan showed a large extensive epidural lesion with compression of the dural sac in the D6–L2 segment, and a left paravertebral extension through the L1–L2 foramen. Laminotomy was performed, with subtotal resection of the lesion. The histopathological and immunohistochemical analyses indicated Ewing sarcoma. Due to the child's age, radiotherapy was not performed, only chemotherapy, due to the aggressiveness of the neoplasm. The patient showed rapid tumor recurrence and ended up dying. Discussion Extraskeletal Ewing sarcoma can appear in different locations in the body. They are aggressive tumors with local recurrence and distant metastases. In our case, a combination of MRI and positron-emission tomography–computed tomography scan presented a clearer result, especially in the presence of metastasis. In the histopathological analysis, small blue cells with a clear cytoplasm and indistinct nucleoli were observed. In the immunohistochemical analysis, CD99 (MIC2) expression is highlighted. The best treatment outcome would have been surgical resection with chemotherapy and radiotherapy. Conclusion We reported a rare case of thoracolumbar epidural Ewing sarcoma in which, despite surgery and chemotherapy, the tumor behaved very aggressively, leading to an unfavorable prognosis.