Primary intracranial Ewing sarcoma with an unusually aggressive course: a case report and review of the literature

Conventional and advanced MR imaging findings of primary Ewing sarcoma of the tentorium: a case report with literature review

BACKGROUND

Primary intracranial Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) is an extremely uncommon tumor. Care should be taken as it can be mistaken for a meningioma radiologically.

CASE DESCRIPTION

This paper reports a case of a 44-year-old male presenting with headache. A magnetic resonance imaging demonstrated a mass involving the tentorium, cerebrum and cerebellum with solid-cystic component. The solid component was hyperintense on T1-weighted images with significant enhancement. There was restriction in diffusion-weighted images and microhemorrhagic signal change in susceptibility weighted images. MR perfusion revealed increased relative cerebral blood volume and mean transit time values. Surgical pathology was reported as ES.

CONCLUSIONS

Intracranial ES/pPNET is a rare tumor that generally arises from the meninges. It must be distinguished from meningioma since it can be mistaken radiologically, because the treatment and prognosis are quite different. Localization and conventional MR signal characteristics of both lesions are similar. Whereas, MR perfusion findings may be helpful in discrimination.

Primary Intracranial Ewing Sarcoma With EWSR1-FLI1 Gene Translocation Mimicking a Meningioma and a Multidisciplinary Therapeutic Approach: A Case Report and Systematic Review of Literatures

Ewing sarcoma and peripheral primitive neuroectodermal tumor (ES/pPNET) is an undifferentiated malignant tumor that is most prevalent in children and young adults and often radiologically mimics a meningioma. A 38-year-old female patient visited our hospital with complaints of right-sided tinnitus, right hemiparesis, and imbalance. She underwent preoperative imaging and was subsequently diagnosed as having a meningioma on the petrous ridge. After partial resection, EWSR1-FLI1 gene fusion was confirmed, and she was diagnosed with ES/pPNET. The tumor was successfully treated using a multidisciplinary approach of adjuvant chemo- and radiotherapy. This case is noteworthy because it is an extremely rare case of an intracranial ES/pPNET, and it is worth sharing our clinical experience that the tumor was successfully treated through a multidisciplinary therapeutic approach even though complete resection was not achieved.

Primary Intracranial Ewing Sarcoma Invading the Superior Sagittal Sinus with EWSR1-FLI1 Gene Fusion and EWSR1 Gene Mutation: A Case Report and Literature Review

BACKGROUND

Primary intracranial Ewing sarcoma (ES) is an extremely rare intracranial malignant tumor, mostly occurring in children and adolescents. Because of its rarity, the magnetic resonance imaging (MRI) features and treatment strategies of primary intracranial ES are still unclear.

METHODS

The purpose of this study was therefore to report a case of primary intracranial ES, whose molecular features included both EWSR1-FLI1 (EWS RNA binding protein 1- Friend leukemia integration 1) gene fusion and EWSR1 gene mutation. It is worth noting that this is the first reported case of ES invading the superior sagittal sinus and mostly causing occlusion. At the same time, there were polymorphisms of four drug metabolism-related enzymes in the tumor. Subsequently, we conducted a literature review to characterize the clinical features, imaging findings, pathological features, treatments, and prognoses of primary intracranial ESs.

RESULTS

A 21-year-old female was admitted to the hospital with headache with nausea and vomiting for 2 weeks. An MRI showed a 3.8 × 4.0 cm large heterogeneous mass in the bilateral parietal lobe with peritumoral edema. The tumor invaded the superior sagittal sinus and mostly caused occlusion of the middle segment of the superior sagittal sinus. The mass was successfully removed using a neuromicroscope. Postoperative pathology indicated a primary intracranial ES. High throughput sequencing (next generation sequencing) showed that there was EWSR1-FLI1 gene fusion and EWSR1 gene mutation in the tumor, with polymorphisms of four drug metabolism-related enzymes and low tumor mutational burden. Subsequently, the patient received intensity modulated radiation therapy. The patient has signed an informed consent form.

CONCLUSIONS

The diagnosis of primary intracranial ES depended on histopathology, immunohistochemistry staining, and genetic testing. At present, total tumor resection combined with radiotherapy and chemotherapy is the most effective treatment. We report the first case of primary intracranial ES invading the superior sagittal sinus and causing middle segment occlusion, accompanied by EWSR1-FLI1 gene fusion and EWSR1 gene mutation.

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.

Aggressive primary sinonasal Ewing sarcoma with intraorbital and intracranial extension

Ewing sarcoma (ES) of the extraskeletal form is a rare occurrence and even rarer to manifest in the sinonasal tract. We describe a case of an advanced sinonasal ES with orbital and intracranial extension that was managed with chemotherapy and endoscopic surgery. Despite completing chemotherapy and surgical resection, the tumor progressed rapidly even before postoperative radiotherapy, and subsequently, she succumbed to death due to sepsis. We would like to discuss the management challenges, pitfalls, and surgical approach which may improve the outcome of this complicated disease.

Educational Case: Ewing Sarcoma of Bone

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, seehttp://journals.sagepub.com/doi/10.1177/2374289517715040. ¹.

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.

The spectrum of rare central nervous system (CNS) tumors with EWSR1-non-ETS fusions: experience from three pediatric institutions with review of the literature

The group of CNS mesenchymal (non‐meningothelial) and primary glial/neuronal tumors in association with EWSR1‐non‐ETS rearrangements comprises a growing spectrum of entities, mostly reported in isolation with incomplete molecular profiling. Archival files from three pediatric institutions were queried for unusual cases of pediatric (≤21 years) CNS EWSR1‐rearranged tumors confirmed by at least one molecular technique. Extra‐axial tumors and cases with a diagnosis of Ewing sarcoma (EWSR1‐ETS family fusions) were excluded. Additional studies, including anchored multiplex‐PCR with next‐generation sequencing and DNA methylation profiling, were performed as needed to determine fusion partner status and brain tumor methylation class, respectively. Five cases (median 17 years) were identified (M:F of 3:2). Location was parenchymal (n = 3) and undetermined (n = 2) with topographic distributions including posterior fossa (n = 1), frontal (n = 1), temporal (n = 1), parietal (n = 1) and occipital (n = 1) lobes. Final designation with fusion findings included desmoplastic small round cell tumor (EWSR1‐WT1; n = 1) and tumors of uncertain histogenesis (EWSR1‐CREM, n = 1; EWSR1‐CREB1, n = 1; EWSR1‐PLAGL1, n = 1; and EWSR1‐PATZ1, n = 1). Tumors showed a wide spectrum of morphology and biologic behavior. For EWSR1‐CREM, EWSR1‐PLAGL1 and EWSR1‐PATZ1 tumors, no significant methylation scores were reached in the known brain tumor classes. Available outcome (4/5) was reported as favorable (n = 2) and unfavorable (n = 2) with a median follow‐up of 30 months. In conclusion, we describe five primary EWSR1‐non‐ETS fused CNS tumors exhibiting morphologic and biologic heterogeneity and we highlight the clinical importance of determining specific fusion partners to improve diagnostic accuracy, treatment and monitoring. Larger prospective clinicopathological and molecular studies are needed to determine the prognostic implications of histotypes, anatomical location, fusion partners, breakpoints and methylation profiles in patients with these rare tumors.

Optimum treatment for primary intracranial Ewing sarcoma

Ewing sarcoma (ES) is an aggressive, high-grade neuroectodermal neoplasm that frequently manifests in children and young adults. Although ES without osseous involvement most commonly involves paravertebral regions of the spine, it very rarely presents as a primary intracranial tumor. This report discusses a unique presentation of an adult extraosseous ES arising from the pineal region with extension into the third and fourth ventricles and multiple drop metastases to the spine. This case demonstrates the application of current chemotherapeutic and adjuvant management and offers insight into possible treatment modalities for metastasis in an atypical extraosseous ES involving the brain and spine.

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.

Intracranial Ewing sarcoma with whole genome study

INTRODUCTION

Ewing sarcoma (ES) as a primary intracranial tumor is very rare. Recently, CNS embryonal tumors with ES-like genomic change have been reported. Patients and methods We report a case of intracranial Ewing sarcoma in a 13-year-old girl who complained of headache and migraine. The tumor had developed in the right middle cranial fossa with a mass effect on the brain with impending transuncal herniation.

RESULTS

Undifferentiated small round cell morphology with completely negative results for friend leukemia integration 1 transcription factor (Fli-1) and a nonspecific cytoplasmic CD99-positive staining pattern mislead the diagnosis as central nervous system (CNS) embryonal tumor, NOS. However, whole genome sequencing (WGS) revealed Ewing sarcoma (EWS)-Fli-1 gene fusion, which was confirmed by fluorescence in situ hybridization study and the diagnosis was revised to ES.

CONCLUSIONS

This case is a true intracranial but extra-axial ES confirmed by WGS. We report this case of intracranial ES to demonstrate the importance of marker gene studies using FISH or NGS.

Clinical Features and Long-Term Outcome of Primary Intracranial Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumors: 14 Cases From a Single Institution

OBJECTIVE

Primary intracranial Ewing sarcoma (ES)/peripheral primitive neuroectodermal tumors (pPNETs) are extremely rare, and only a few studies have reported >4 cases of this disease. The purpose of this study was to explore the clinical features, treatment, and outcome of primary intracranial ES/pPNETs.

METHODS

The clinical data of 14 patients who had been surgically treated from February 2003 to November 2017 and in whom immunohistochemical staining results had confirmed the diagnosis of primary intracranial ES/pPNETs were retrospectively analyzed. Kaplan-Meier survival analysis was used to estimate the survival rate and the median survival time (MST).

RESULTS

Gross total resection (GTR) was achieved in 7 cases, and subtotal resection was performed in 7 cases. During follow-up, 10 (71.4%) patients had local recurrence and 3 (21.4%) patients had distant metastasis. The overall 1-, 2-, and 5-year survival rates were 78.6%, 47.6%, and 19.0%, respectively. Kaplan-Meier survival analysis showed that postoperative radiotherapy was a significant prognostic factor for longer MST (P = 0.034). GTR and radiotherapy with or without adjuvant chemotherapy yielded the highest 2-year survival rate (100%). Three patients who underwent GTR, radiotherapy, and chemotherapy had the highest 2-year survival rates (100%) and the longest MST (48 months).

CONCLUSIONS

Primary intracranial ES/pPNETs have an aggressive clinical course, with a high tendency for local recurrence and distant metastasis. Radiotherapy plays a significant role in improving the survival of patients. GTR combined with radiotherapy and chemotherapy may be the most beneficial treatment modality.

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.

Skull and Spinal Ewing's Sarcoma in Children: An Institutional Study

Background:

Ewing’s sarcoma is a disease of children and young adults and occurs most often in bone and soft tissues. The intracranial and spinal manifestation of the disease is rare and reported incidence is 1%–6%.

Aims and Objectives:

We conducted this study to determine the surgical outcome of children with skull and spine Ewing’s sarcoma (SSES).

Methods:

This is a prospective analysis of 13 patients of SSES who reported to the Department of Neurosurgery, Nizam’s Institute of Medical Sciences, Hyderabad, Telangana, India, between 2014 and 2016. All cases after detailed examination, magnetic resonance imaging, and computed tomography scan were subjected to surgery followed by adjuvant therapy comprising chemotherapy and radiotherapy. Outcome was analyzed at 6 months as well at latest follow-up. Neurological function, local recurrence, primary or secondary nature of the disease, distant relapse, and treatment-related complications were analyzed in this study.

Results:

There were eight female and five male patients with a mean age of 12 years (ranging from 4 to 8 years). Pain was the common presenting feature in all cases. Focal neurological deficits corresponding to the anatomical location was seen in six patients. These 13 cases were distributed anatomically as four cases involving the cloves, two cases with occipital bone and lobe involvement, one case of parietal bone and lobe involvement, and six cases of spinal involvement. Surgery was performed in all cases where gross total excision (Ozge C, Calikoglu M, Cinel L, Apaydin FD, Ozgür ES. Massive pleural effusion in an 18-year-old girl with Ewing sarcoma. Can Respir J 2004;11:363-5), near-total excision, and subtotal excision was achieved in these 13 cases (Steinbok P, Flodmark O, Norman MG, Chan KW, Fryer CJ. Primary Ewing’s sarcoma of the base of the skull. Neurosurgery 1986;19:104-7). Subsequently all cases underwent multiagent chemoradiotherapy. Postsurgery pain subsided in 12 (92%) of patients. Ten patients maintained or improved motor function. In seven cranial cases and in six spinal cases, four cases showed improvement whereas three (23%) had deterioration of motor function.

Conclusions:

Surgical outcome of SSES in short-term follow-up is good with current recommended management regimen of maximum excision followed by chemo and radiotherapy. However, metastasis is not uncommon.

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.

First Case of Primary Sellar/Suprasellar-Intraventricular Ewing Sarcoma: Case Report and Review of the Literature

BACKGROUND

Intracranial Ewing sarcoma (ES) and peripheral primitive neuroectodermal tumors (pPNETs) are extremely rare and poorly differentiated neoplasms. Immunohistochemical and cytogenetic findings support the possibility of a unique nosologic entity. Primary intracranial localization of this tumor is extremely rare; a few cases are reported in the literature, with only some confirmed by genetic studies.

CASE DESCRIPTION

We report a 12-year-old patient with a sellar/suprasellar mass with intraventricular extension that in all its features mimicked a transinfundibular craniopharyngioma. The patient underwent complete resection of the lesion via an endoscopic endonasal transtuberculum approach 6 days after ventriculoperitoneal shunt for acute obstructive hydrocephalus. Histopathologic and genetic examination demonstrated ES/pPNET. The diagnosis was confirmed by detection of a rearrangement of the EWSR1 gene by fluorescent in situ hybridization and identification of the diagnostic t(11;22) translocation by reverse transcriptase polymerase chain reaction. The patient remained in complete clinical remission 12 months after tumor resection followed by adjuvant chemotherapy with no radiologic evidence of tumor recurrence.

CONCLUSIONS

To our knowledge, this is the first case of primary intrasellar/suprasellar-intraventricular ES/pPNET confirmed by molecular genetic analysis. Extensive investigations, including pathologic, immunohistochemical, and genetic studies, are needed for differentiation of these tumors from other, more common sellar/suprasellar tumors. Our case highlights that an interdisciplinary therapeutic approach is mandatory to guarantee a favorable outcome.

Primary Ewing's sarcoma of the sinonasal tract, eroding the ethmoid and sphenoid sinus with intracranial extension: A rare case report

Ewing's sarcoma (ES) is an aggressive tumour that may present with skeletal and extraskeletal forms. The extraskeletal form is rarely encountered in the head and neck region and is extremely rare in the sinonasal tract. This is the case report of a ES of the ethmoid sinus with intracranial and orbital extension in a 33-year-old male patient who presented with anosmia, epistaxis, reduction of visual acuity in the left eye and headache. On otorhinolaryngological clinical examination and biopsy via flexible endoscope, the lesion was misdiagnosed as ethmoid sinus carcinoma. The subsequent magnetic resonance imaging (MRI) of the brain revealed a large mass (6×7 cm) eroding the ethmoid and sphenoid sinuses, extending beyond the orbits and occupying the anterior cranial fossa with a maximum extension of ~5 cm. The patient underwent surgical resection and the microscopic examination of the specimen established the diagnosis of ES (immunohistochemically positive for CD99, neuron-specific enolase, CD56, synaptophysin, pancytokeratin, low-molecular weight cytokeratins and vimentin. The periodic acid Schiff stain exhibited strong intracytoplasmic block positivity and fluorescence in situ hybridization revealed a t(22;11) translocation. First-line chemotherapy was administered for 3 cycles; however, on restaging MRI, local disease progression was diagnosed. The patient received radiotherapy and second-line chemotherapy for 6 cycles. At 15 months after the diagnosis, the patient remains recurrence-free and maintains a good functional status and quality of life.

Epidemiological trends of histopathologically WHO classified CNS tumors in developing countries: systematic review

BACKGROUND

Many developing countries are lagging behind in reporting epidemiological data for individual central nervous system (CNS) tumors. This paper aimed to elicit patterns for the epidemiology of individual World Health Organization (WHO) classified CNS tumors in countries registered by WHO as "developing".

MATERIALS AND METHODS

Cyber search was carried out through 66 cancer networks/registries and 181 PubMed published papers that reported counts of CNS tumors for the period of 2009-2012. The relationship between the natural log of incidence Age Standardized Rate (ASR) reported by Globocan and Latitude/ Longitude was investigated.

RESULTS

Registries for 21 countries displayed information related to CNS tumors. In contrast tends for classified CNS tumor cases were identified for 38 countries via 181 PubMed publications. Extracted data showed a majority of unclassified reported cases [PubMed (38 countries, 45.7%), registries (21 countries, 96.1%)]. For classified tumors, astrocytic tumors were the most frequently reported type [PubMed (38 countries, 1,245 cases, 15.7%), registries (21 countries, 627 cases, 1.99%]. A significant linear regression relationship emerged between latitudes and reported cases of CNS tumors.

CONCLUSIONS

Previously unreported trends of frequencies for individually classified CNS tumors were elucidated and a possible link of CNS tumors occurrence with geographical location emerged.

Ewing sarcoma of the posterior fossa in an adolescent girl

Medulloblastoma, astrocytoma, and ependymoma represent the most common infratentorial tumors in childhood, while Ewing sarcomas in that localization are extremely rare. A large left infratentorial space-occupying lesion was diagnosed in a 12-year-old girl with signs of increased intracranial pressure. Following total tumor resection, histological and molecular examination revealed Ewing sarcoma with rearranged EWSR-1 gene. The patient achieved complete remission following adjuvant chemotherapy and radiotherapy according to Euro-EWING 2008 treatment protocol. Intracranial Ewing sarcoma, although rare, should be an important differential diagnosis of intracranial tumors in childhood which requires aggressive multimodal treatment.

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.