Primary extraosseous intracranial Ewing's sarcoma: Case report and literature review

Brain Metastasis With a Solitary Lesion Secondary to Knee Joint Ewing Sarcoma: A Case Report

Brain metastasis from Ewing sarcoma is rare and can present with various symptoms. We present a 21-year-old female who underwent surgery for Ewing sarcoma of the knee joint and, after six months, was reported with complaints of headache and vomiting. Considering recommended investigations, metastatic Ewing sarcoma of the brain was diagnosed, and a treatment protocol, such as a combination of surgery, chemotherapy, and radiation, was given. Our observation shows this is the first case reported with a solitary metastatic brain lesion associated with Ewing sarcoma.

Intracranial extraosseous dural-based Ewing's sarcoma with fluid-haematocrit levels: imaging findings of a rare tumour

Extraosseous dural-based primary Ewing's sarcoma of the central nervous system is a rare tumour posing a diagnostic challenge. On cross-sectional radiological imaging, the lesion has an extra-axial location with heterogeneous appearance. These lesions are usually multicystic with internal haemorrhage causing fluid-haematocrit levels. It mimics conditions like an aneurysmal bone cyst, microcystic meningioma, telangiectatic osteosarcoma or cystic metastasis. Exclusion of primary Ewing's sarcoma or malignancy elsewhere in the body is required to rule out a secondary. Surgery along with adjuvant chemotherapy and focal radiotherapy is the preferred mode of treatment. Due to the presence of non-specific small round blue cells on H&E stain, these tumours are also confused with lymphoma, osteosarcoma, rhabdomyosarcoma, Merkel cell carcinoma, ependymoblastoma and neuroendocrine carcinoma. Immunohistochemistry provides a definitive diagnosis. A high degree of suspicion in the preoperative scans is crucial for prognostication and early management of this aggressive tumour leading to improved patient survival.

Primary intracranial Ewing sarcoma/ peripheral primitive neuroectodermal tumor, an entity of unacquaintance: a series of 8 cases

PURPOSE

The purpose is to highlight the primary intracranial (meningeal-based) occurrence of Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET).

METHODS

This report is a collation of clinicopathological features of eight cases of molecularly and clinicoradiologically confirmed primary (non-metastatic) intracranial (non-osseous) meningeal ES/PNET.

RESULTS

The age range was 1 to 33 years with a median age of 9 years. Male to female ratio was 0.6:1. All patients were diagnosed on the debulking surgical material (gross total resection, 2 cases; subtotal resection, 6 cases) and showed primitive embryonal histomorphology with diffuse membranous CD99 immunoexpression and EWSR1 gene rearrangement by fluorescence in situ hybridization. Seven of them showed a typical FISH pattern of split signals with break-apart probe, while one showed an unusual signal pattern of loss of green signals. EFT-2001 adjuvant protocol was followed along with focal radiotherapy (RT) in all cases (except case 8, full course of chemotherapy could not be completed). Two cases had local recurrence-one of them died of disease recurrence before the administration of further treatment.

CONCLUSION

This series adds non-osseous intracranial site to the list of uncommon sites of occurrence for ES/PNET and more importantly emphasizes the need to be considered in a differential list of primary intracranial primitive embryonal tumors before embarking as primary central nervous system (CNS) embryonal tumor, NOS.

Ewing Sarcoma With Emphasis on Extra-skeletal Ewing Sarcoma: A Decade's Experience From a Single Centre in India

INTRODUCTION

The diagnosis of Ewing sarcoma family of tumours (ESFT) is challenging, especially in adults and in extra-skeletal or visceral location. Several morphologic mimics with varied treatment options and prognosis confer diagnostic dilemmas. Application of ancillary diagnostic modalities in surgical pathology in clinical routine has enabled accurate diagnosis of ESFT in bone, soft tissues, and viscera.

AIM

The study aims to assess the clinicopathological features including molecular test results of ESFT with emphasis on sex, age, and location, especially extra-skeletal soft tissue and visceral location.

MATERIAL AND METHODS

Data of clinicopathological, molecular tests (wherever performed), diagnosis rendered in 302 ESFT over a decade from our centre were reviewed. Statistical comparison of skeletal and extra-skeletal tumours with reference to age and sex was done using SPSS package. The P value of <.05 was considered significant.

RESULTS

The cohort included 302 ESFTs with 49% skeletal and 51% extra-skeletal tumours. Thigh was most common site among skeletal tumours; chest wall, paraspinal location, and retroperitoneum among soft tissues (39.4%); and kidney, ovary, and cervix among visceral tumours (11.3%). Fluorescence in situ hybridisation for EWSR1 gene rearrangement was positive in 54 patients and reverse-transcriptase polymerase chain reaction in 19 patients. Predominance of male sex, younger age and location in extremities among skeletal tumours and lack of gender predilection, higher age and axial location in extra-skeletal tumours were noted, which were statistically significant. Molecular tests were performed more frequently in extra-skeletal tumours, especially in visceral tumours to establish the diagnosis.

CONCLUSIONS

The study showed statistically significant differences in the age, sex, and location between skeletal and extra-skeletal ESFT. The increased percentage of extra-skeletal tumours especially in viscera was attributed to the increased awareness and availability of ancillary techniques.

Cranial Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumors: A Retrospective Study Focused on Prognostic Factors and Long-Term Outcomes

Purpose: Cranial Ewing sarcoma (ES)/peripheral primitive neuroectodermal tumors (pPNETs) are rarely reported because of their extremely low incidence, and the current understanding of these tumors is poor. The purpose of this study was to illustrate the clinical, radiological, and pathological features of cranial ES/pPNETs and to discuss prognostic factors by survival analysis.

Methods: A total of 31 patients who were pathologically diagnosed with cranial ES/pPNETs between 2000 and 2019 were enrolled in this study. To identify which parameters were associated with higher progression-free survival (PFS) and overall survival (OS) rates, univariate and multivariate analyses were performed.

Results: The mean follow-up period was 24.8 months (range, 1–109 months). Eighteen (58.1%) patients had local recurrence and seven (22.6%) patients had distant metastasis. The results of the univariate analysis suggest that the extent of resection and adjuvant radiotherapy are potential prognostic factors for PFS and OS. Adjuvant chemotherapy was associated with OS (P = 0.027) but not with PFS (P = 0.053). The multivariate analysis revealed that the extent of resection and adjuvant radiotherapy were independent prognostic factors for both PFS and OS. In addition, metastasis was an adverse prognostic factor for OS.

Conclusions: Surgical management plays a crucial role in the treatment of cranial ES/pPNETs, and gross total resection should be striven for whenever possible. Post-operative radiotherapy is highly recommended to improve PFS and OS. This study also confirms that metastasis is an adverse prognostic factor for cranial ES/pPNETs.

Primary intracranial extraosseous Ewing's sarcoma

INTRODUCTION

Common sites of occurrence of extraosseous Ewing's sarcoma include the soft tissues and bones of the lower extremity, 12 paravertebral, and retroperitoneal regions. Primary intracranial Ewing's sarcoma/pPNET is usually intraparenchymal located 13 when supratentorially, and an extraaxial epidural tumor radiographically mimicking a meningioma is extremely rare.

CASE PRESENTATION

A 20-year14 old male presented to the emergency department with a 1-day history of drowsiness, headache, and fever. Neurological exam15 ination revealed decreased muscle strength (4/5) in the left lower limb. Head computed tomography scan showed an epidural 16 space-occupying lesion in the right temporoparietal region, which was assumed to be a meningioma by radiographic criteria. However, the surgical specimen was diagnosed as Ewing's sarcoma.

CONCLUSION

Primary intracranial extraosseous Ewing's sarcoma is a rare condition that may mimic a meningioma on imaging. Physicians must be cognizant of this possibility, particularly in any young individual with a solitary contrast-enhancing dural-based lesion.

An unusual biconvex epidural lesion: acutely presenting extraosseous intracranial Ewing's sarcoma

Background

Ewing’s sarcoma family of tumors consists of small round cell neoplasms, inclusive of primitive neuroectodermal tumor (PNET), Askin’s tumor, and PNET of the bone. Extraosseous Ewing’s sarcoma occurs commonly at bones of lower extremities and paravertebral region of the spine. It rarely presents as a primary intracranial lesion. When intracranial, it can be misdiagnosed as central PNET (e.g., medulloblastoma, pinealoblastoma, or supratentorial PNET), other intracranial lesions, or even as an epidural hematoma.

Case presentation

We report the case of a 20-year-old patient who presented to the emergency department with complaints of drowsiness, headache, and fever for 1 day. On initial computed tomography (CT) scan of the brain, a right temporal biconvex epidural lesion involving squamous-temporal bone with periosteal reaction was noted.

The patient underwent urgent craniotomy, and a tumor was found and excised. Biopsy report confirmed Ewing’s sarcoma.

Conclusion

Ewing’s sarcoma is a rare intracranial malignancy with only a few cases reported in literature. In a young patient with a biconvex epidural lesion, in the absence of trauma or ongoing infection, the possibility of Ewing’s sarcoma should be considered as well.

Primary Intracranial pPNET/Ewing Sarcoma: Diagnosis, Management, and Prognostic Factors Dilemma-A Systematic Review of the Literature

BACKGROUND

Ewing sarcoma (ES) is a malignant bone tumor that is most commonly observed in the long bones, the pelvis, and the chest. Primary intracranial localization is extremely rare.

OBJECTIVE

In the aim of identifying the prognostic factors of this rare localization, we conducted a systematic review of the literature for patients with primary intracranial peripheral primitive neuroectodermal tumor/ES.

METHODS

A complete MEDLINE search was undertaken for all articles reporting data for primary intracranial peripheral primitive neuroectodermal tumor/ES. We divided the patient population into 2 groups: group I, patients who were free of disease; and group II, patients who died or had uncontrolled disease at the last available follow-up. We conducted a comparative statistical analysis of data between the 2 groups.

RESULTS

A total of 48 patients were included in the review. There were 32 patients in group I and 12 in group II. Fifty percent of tumors in group II and only 16% of tumors in group I were infratentotorial (P = 0.03). Signs of bone involvement were observed in 19% of patients in group I and 54% in group II (P = 0.03). Total removal was accomplished in 29% of patients in group I and in no patients in group II (P = 0.03). Radiotherapy was performed in 73% of patients in group II and 81% in group I (P = 0.43). Chemotherapy was administered in 36% of patients in group II and 74% in group I (P = 0.03).

CONCLUSIONS

Infratentorial localization and the presence of bone involvement were associated with poor prognosis; Surgery seems to be a predictive factor of prognosis; radiotherapy and chemotherapy must be performed whenever the tumor is not totally removed.

Intracranial Ewing sarcoma: four pediatric examples

BACKGROUND

Ewing sarcoma typically arises in bone and is unrelated to intraparenchymal small blue cell embryonal central nervous system (CNS) tumors previously designated primitive neuroectodermal tumors (PNETs). When the CNS is impacted, it is usually secondary to local extension from either the epidural space, skull, or intracranial or spinal metastases. Primary examples within the cranial vault are rare, usually dural-based, and are largely case reports in the literature. We detail four pediatric patients with solitary, primary intracranial Ewing sarcoma, all manifesting the archetypal EWRS1 gene rearrangement that confirms diagnosis.

PROCEDURE

Neurosurgical Department records, spanning 21 years (1995-2016), were reviewed to identify patients. Demographics, clinical history, pathological/genetic features, and clinical course were retrieved from the medical record and personal files of the authors.

RESULTS

Four patients, one male and three females, age 5 to 16 years, were identified. One presented in extremis from a large lesion, two with soft tissue masses, and the fourth as an incidental finding after being involved in a motor vehicle collision. Three had clear bony involvement: a 10-year-old girl with a large left temporal lesion had clear origin in the skull, with spiculated calcified striations throughout the mass; a 9-year-old girl presented with a bony left petrous apex mass; and a 16-year-old girl presented with a left temporal mass with extension to the dura and underlying bone erosion. Only the 5-year-old boy had a large left frontoparietal mass traversing the falx with no bony contact. All four tumors manifested the diagnostic EWSR1 mutation and were treated with an Ewing sarcoma regimen. Outcomes were variable, with one patient showing progressive metastatic disease and death 3 years after presentation, one patient with disease-free survival 10.5 years after completion of therapy, and one alive and well at the completion of therapy 1 year after diagnosis. One patient completed therapy recently with post-therapy scans showing no evidence of disease.

CONCLUSION

Testing for the EWSR1 mutation confirms the diagnosis of Ewing sarcoma and excludes other types of embryonal CNS tumors. Long-term disease-free survival is possible with adherence to the appropriate therapeutic regimen after gross surgical resection.

Primary Ewing's Sarcoma of the Temporal Bone: A Rare Case Report and Literature Review

Ewing's sarcoma is a malignant, round cell tumor arising from the bones and primarily affecting children and adolescent, accounting for 3 % of all childhood malignancies. Although the long bones and the trunk are typically affected, rare cases of it involving isolated bones throughout the body have been reported. Involvement of the skull bones is rare, constituting 1-6 % of the total Ewing's sarcoma cases but those affecting the cranial bones are rarer still, constituting only 1 %. We describe an 8 months old infant having Ewing sarcoma, of the petrous and mastoid parts of temporal bone along with the occipital bone, whose clinical presentation mimicked mastoiditis with facial nerve palsy. We discuss the clinical and therapeutic course of an extensive primary Ewing sarcoma of the temporal bone, which was treated without performing surgery and review this entity's literature in detail.

Imaging of the Sella and Parasellar Region in the Pediatric Population

Masses in the sella and parasellar region comprise about 10% of all pediatric brain tumors but type and frequency differs from those in adults. Imaging is critical for diagnosis and characterization of these lesions. By assessing the site of origin, signal and contrast enhancement characteristics, and the presence or absence of characteristic patterns, differential diagnosis can narrow the possibilities. The clinical presentation is often characteristic for lesion type and should be considered. This article summarizes the characteristic imaging features of the most frequent pediatric tumors and tumor-mimicking lesions in children in this region.

Primary intracranial dural-based Ewing sarcoma/peripheral primitive neuroectodermal tumor mimicking a meningioma: A rare tumor with review of literature

Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) is a malignant small, round cell tumor arising from bone and soft tissue in children and young adults. It can occur at osseous and extraosseous sites. Its usual locations are diaphysis of long bones followed by pelvis, ribs, vertebrae, and rarely skull. We reviewed the literature and PubMed advanced search on ES/pPNET occurring at extraosseous sites, mainly involving the central nervous system (CNS). We reported a case of a 22-year-old male presenting with seizure finally diagnosed as a case of ES/pPNET. The challenges in management of this rare CNS tumor and its differential diagnosis are highlighted. We found that most cases of ES involving CNS represent secondary metastases from extracranial sites of ES/pPNET and there are rare case reports of primary intracranial ES-pPNET. Furthermore, among these intracranial tumors, most common tumors occupy an intraaxial location and only a handful of cases of dural-based or extraaxial tumors mimicking meningioma are reported. Differentiation of pPNET from central PNET (cPNET) is important as it has definitive therapeutic and prognostic implications. Awareness of this entity of ES/pPNET, its rare dural presentation, and differentiation from the more common cPNET is needed for appropriate patient management. Meningeal ES/pPNET has to be kept in mind in the differential diagnosis of meningeal tumors eroding bone.

Epileptic seizure in primary intracranial sarcoma: a case report and literature review

PURPOSE

The aim of this study is to describe epileptic seizures in patients with primary intracranial sarcomas.

METHODS

We report a 17-year-old girl diagnosed with primary high-grade intracranial sarcoma with initial clinical manifestation of nonconvulsive status epilepticus. Literature reports between 2000 and 2014, relevant to primary intracranial sarcomas in children, were reviewed. The clinical presentations and neurological outcomes were analyzed.

RESULTS

Eleven of 29cases (38 %), 8 males and 3 females, who exhibited epileptic seizures as one of the initial symptoms and diagnosed with primary intracranial sarcomas were collected. The median age of disease onset was 5 years. The two most common seizure types were generalized seizures (45 %) and status epilepticus (36 %). Nine of 11 patients (82 %) had tumor growth involving the frontal lobe. Nine cases had the median duration of follow-up 1.7 years, of which 6 cases showed tumor recurrence and 3 cases died during the period of follow-up.

CONCLUSIONS

Epileptic seizures as one of the clinical manifestations are uncommon. The two most common seizure types were generalized seizures and status epilepticus. The most frequent location of primary intracranial sarcoma-related seizures was the frontal lobe. The clinical outcome varied.

Synthetic treatment of intracranial peripheral primitive neuroectodermal tumor with multiple metastasis: a case report

Ewing sarcomas (ES) and peripheral primitive neuroectodermal tumors (pPNET) are now thought to belong to the same tumor family. Ewing sarcoma family tumor (ESFT) members commonly originate in bones and soft tissues. However, a few published articles describe ESFT arising from cranial cavities. Pathologically, ES/pPNET are composed of small round cells. Unambiguous distinction between pPNET and other small round cell tumors, in particular central PNET, is of clinical significance. Definitive diagnoses of pPNET can be obtained through CD99 (MIC2 gene product) membrane positivities and molecular identifications of chromosomal rearrangements between EWS and ETS family genes. Multimodal approaches comprising surgical resections, radiotherapies, and chemotherapies are required for the treatment of ESFT. Decompressive medical measures are preferentially performed when epidural masses are compressing spinal cords. In cases of ES-induced brain herniations, emergent radiotherapies may serve as effective tools. We report a case of multiple disseminated intracranial ES/pPNET for which synthetic treatments were used.

Primary intracranial Ewing's sarcoma with unusual features

Pediatric primary "small round blue cell" tumors in the CNS represent several entities, some more common than others. Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) is rare and must be distinguished from other tumors such as medulloblastoma [1, 2], atypical rhabdoid/teratoid tumor, ependymomal tumors, metastatic sarcomas, hematologic malignancies, and other mimics. Although therapy for ES/pPNET is effective, it brings severe side effects, including cardiac toxicity, making correct recognition important [3]. As small blue cell tumors look similar, diagnosis often depends on special stains, immunohistochemistry, and molecular techniques. While the combination of membranous immunohistochemical reactivity for CD99 with cytoplasmic glycogen provides effective screening, demonstration of characteristic translocations of EWSR1 (chromosome 22) or FUS (chromosome 16) by fluorescent in situ hybridization (FISH) can confirm the diagnosis. We are reporting three primary ES/pPNET of the CNS, two of which occurred in children. While the adult case demonstrates the classic histopathology, the two pediatric cases have histopathology that significantly deviates from the usual. One is suggestive of a primary sarcoma, and the other mimics an ependymoma, but all three cases are confirmed with FISH. These observations suggest that primary ES in the CNS may have histology different from the classic morphology and a high index of suspicion should be maintained in order to make the correct diagnosis. A search of the literature suggests that these tumors are most frequently seen in children and young adults. Imaging often shows a supratentorial enhancing mass that touches the leptomeninges. Survival over three years is good but long term prognosis is unknown [3, 4].

Dural metastasis of Ewing's sarcoma

BACKGROUND

Metastatic Ewing's sarcoma to the central nervous system is an uncommon condition and debate concerning the true origin of its metastases is still up to date. To the best of our knowledge, only two cases of dural metastatic Ewing's sarcoma have been published in the English medical literature. We present an additional case in a 24-year-old female and discuss the pathogenesis of these unusual tumors with review of the relevant literature concerning their treatment and outcome.

CASE DESCRIPTION

A 24-year-old female with previous history of pelvis Ewing's sarcoma and recently discovered lung metastases, presented with moderate headache for the past 2 weeks and weakness in her left leg for the past 2 days. Computed tomography scan and magnetic resonance imaging revealed an extra-axial right frontoparietal mass invading the superior sagittal sinus but with clear delineation with brain parenchyma. Imaging features were suggestive of a meningioma as no abnormalities in the skull abutting to the tumor were noted. The patient underwent surgical removal of her tumor. Near total resection was achieved and histological examination showed evidence of metastatic Ewing's sarcoma. Postoperative adjuvant radiation and chemotherapy were administered. The patient improved well postoperatively with full recovery of her motor weakness. She is symptom free with no signs of progression, at most recent follow-up, 8 months after surgery.

CONCLUSION

Despite its rarity, metastatic Ewing's sarcoma must be considered in the differential diagnosis of extra-axial dural masses particularly meningiomas.

What's in a name? Intracranial peripheral primitive neuroectodermal tumors and CNS primitive neuroectodermal tumors are not the same

BACKGROUND

Intracranial peripheral primitive neuroectodermal tumors (P-PNET) are extremely rare. They can be easily misdiagnosed as central nervous system primitive neuroectodermal tumors (CNS-PNET) or meningiomas. Little is known about the optimal treatment and prognosis of these tumors.

PATIENTS AND METHODS

We evaluated the treatment and outcome of 17 patients with intracranial, nonmetastatic, genetically confirmed P-PNET. Three patients were treated at our institutions. Thirteen other cases providing sufficient treatment and follow-up information were extracted from the literature.

RESULTS

The median age at diagnosis was 17 years. All patients underwent initial surgery. Complete resection was achieved in 9 of the 17 cases (53 %). Combined adjuvant treatment consisting of radiotherapy (focal, n = 10; craniospinal, n = 1) and chemotherapy was administered to 11 of the 17 patients (59 %). The median follow-up time was 1.4 years. In 8 of the 17 patients (47 %), the disease progressed; 4 of the 17 patients (24 %) died. The 2-year progression-free and overall survival rates were 64 % and 76 %, respectively.

CONCLUSION

The differential diagnosis for intracranial, meningeal-based, small, round-cell tumors should include P-PNET. It is highly probable that complete resection has a positive impact on survival--as previously reported for extracranial P-PNET--but this cannot be shown by our data. Intensive adjuvant treatment consisting of radiotherapy and chemotherapy seems to be essential. A statistically grounded recommendation for the appropriate target volume and radiation dose is not yet possible. However, in most case reports of primary intracranial P-PNET published to date, patients were treated with focal irradiation. The optimal chemotherapy regimen has yet to be established, with both the Ewing tumor and CNS-PNET protocols being promising candidates for effective treatment.