Ewing Sarcoma/peripheral Primitive Neuroectodermal Tumor Research Articles

The prognostic factors of Ewing sarcoma/peripheral primitive neuroectodermal tumor: A retrospective analysis of 67 patients at a single center.

To investigate the characteristics and factors that impact the prognosis of Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) patients. We retrospectively analyzed ES/pPNET patients diagnosed at our hospital from January 2011 to December 2020. We used 1-way analysis of variance to investigate whether the age differences between different subgroups were statistically significant and used the Kaplan–Meier method and Cox regression model for the survival analysis. Of the 67 included patients, 13 had central nervous system PNET, and 54 had ES/pPNET. The median survival time of the 54 ES/pPNET patients was 18 months; the 1-year, 3-year and 5-year progression-free survival rates were 37.0% and 9.3% and 1.9%, respectively; and the 1-year, 3-year and 5-year overall survival (OS) rates were 66.7%, 27.8%, and 7.4%, respectively. The 1-way analysis of variance results showed no statistically significant age difference between the different subgroups (P = .127 between the central nervous system PNET and ES/pPNET groups, P = .764 between different subgroups within the ES/pPNET group). The univariate survival analysis showed that metastasis at diagnosis and the treatment method were independent factors affecting the OS rate of ES/pPNET patient (P = .003 and 0.000, respectively). The multivariate survival analysis also showed that the treatment method and metastasis at diagnosis were related factors affecting OS (P = .025 and 0.001, respectively). The prognosis of patients with primitive neuroectodermal tumors is poor. The treatment method and metastasis at the time of diagnosis influences ES/pPNET patient survival time, but there is no significant tumor site-dependent correlation with patient age or sex.

Prostate Ewing Sarcoma/PNET: A case of long survival in a highly aggressive malignancy

Prostate Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/PNET) is extremely rare. Currently, a multimodal approach is recommended, although there is no standard treatment. Nevertheless, this tumor has a very poor prognosis, with the longest reported survival of 24 months. We present a case of locally advanced prostate ES/PNET in a 29-year-old male who was treated with a multimodal approach. The patient is alive and disease free, with a seven year follow-up, with very good quality of life. This exceptionally long survival may be the result of the very aggressive multimodal treatment chosen and described herein.

Clinical characteristics and treatment analysis of primary meningeal Ewing sarcoma/peripheral primitive neuroectodermal tumors: A report of 12 cases

Objective To investigate the clinical characteristics, treatment methods and prognosis of primary meningeal Ewing sarcoma/peripheral primitive neuroectodermal tumors (ES/pPNETs). Methods The clinical data of 12 patients who had been surgically treated from February 2008 to December 2017 at Department of Neurosurgery, Tongji Hospital, Tongji Medical School, Huazhong University of Science and Technology and in whom immunohistochemical staining results had confirmed the diagnosis of primary meningeal ES/pPNETs were retrospectively analyzed. A fluorescence in situ hybridization (FISH) analysis was performed in 4 cases.Of the 12 patients, 7 were males and 5 were females. The age ranged from 1 to 43 years, and the median age was 14.5 years. The disease duration ranged from 2 days to 7 months (median disease duration: 2 months). Postoperative chemotherapy was performed in 9 cases. Postoperative radiotherapy was performed in 7 cases. Results All 12 cases were misdiagnosed by MRI. Immunohistochemistry experiments revealed that 12 cases were positive for CD99. A FISH analysis was performed in 4 cases, and EWS/FLI1 translocation was detected in 3 cases.Gross total resection (GTR) was performed in 6 cases and subtotal resection (STR) in 6. The follow-up period ranged from 2 months to 84 months (median follow-up period: 20 months). One case was lost to follow-up after 24 months. At the last follow-up, local recurrence occurred in 7 cases, and distant metastasis occurred in 3 cases. The number of deaths was 9 and that of survivors was 2. The median survival time (MST) of 11 patients was 20 months. Of the 12 patients, the number of survivors in 1-year and 2-year were 9 and 6, respectively. The number of survivors in 1-year and 2-year were 5 and 4, respectively, in patients with GTR, while they were 4 and 2, respectively, in patients with STR. Conclusions Primary meningeal ES/pPNETs mostly occur in children and adolescents, and the misdiagnosed rate seems high. Gross total resection combined with adjuvant radiotherapy and chemotherapy could improve the prognosis of patients. However, the postoperative recurrence rate is high. Key words: Ewing sarcomas; Primitive neuroectodermal tumors; Disease attributes; Treatment; Prognosis

Bone marrow examination in patients with Ewing sarcoma/peripheral primitive neuroectodermal tumor without metastasis based on 18F-fluorodeoxyglucose positron emission tomography/computed tomography

Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/PNET) is an aggressive bone tumor. Bone marrow aspiration and biopsy (BMAB) has been recognized as the gold standard for assessing bone marrow status. While the latest guideline suggests the need to omit bone marrow aspiration in patients with no findings on 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) based on one retrospective report, there is no study using 18F-FDG PET/computed tomography (CT). We retrospectively reviewed 26 consecutive, previously untreated, ES/PNET patients. We compare the results of bone marrow aspiration and biopsy (BMAB) and those of 18F-FDG PET/CT in ES/PNET patients. All of the 21 patients without metastases on 18F-FDG PET/CT had negative BMAB. The sensitivity of bone marrow involvement in bone metastases positive patients on 18F-FDG PET/CT was 75% (3/4), and the specificity was 100% (22/22). In addition to the metastatic findings on 18F-FDG PET/CT, tumor diameter, lactate dehydrogenase level at diagnosis, and the presence or absence of bone metastasis were factors related to bone marrow involvement. It may be a reasonable option to omit BMAB in ES/PNET patients with no distant metastasis based on 18F-FDG PET/CT findings.

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.

Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumor in the Adrenal Gland of an Adolescent

Ewing sarcoma/peripheral primitive neuroectodermal tumors (ES/pPNETs) typically occur in the long or flat bones, the chest wall, extraskeletal soft tissue, or less frequently, in solid organs. They can arise from anywhere in the body; however, ES/pPNETs arising from the adrenal gland are very rare, especially in children and adolescents. Herein, the authors report a case of an ES/pPNET in the adrenal gland of a 17-year-old girl, who was successfully treated with a multimodal treatment, with a brief review of the pertinent literature.

Ewing sarcoma/peripheral primitive neuroectodermal tumor and related tumors.

Ewing sarcoma/peripheral primitive neuroectodermal tumor (EWS/pPNET) and other tumors with EWS gene rearrangements encompass a malignant and intermediate neoplasm with a broad anatomic distribution and a wide age range but a predilection for soft tissue in children, adolescents, and young adults. The overlapping histologic, immunohistochemical and cytogenetic and molecular genetic features create diagnostic challenges despite significant clinical and prognostic differences. Ewing sarcoma is the 3rd most common sarcoma in children and adolescents, and desmoplastic small round cell tumor is a rare neoplasm that occurs more often in older children, adolescents, and young adults. Pathologic examination is complemented by immunohistochemistry, cytogenetics, and molecular genetics. This article reviews the clinicopathologic features of EWS/pPNET and desmoplastic small round cell tumor in the spectrum of tumors with EWS gene rearrangements. Other tumors with different histopathologic features and an EWS gene rearrangement are discussed elsewhere in this volume.

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

The occurrence of Ewing sarcoma-peripheral primitive neuroectodermal tumor as a primary intracranial tumor is very rare, with only 29 cases reported in the literature, 19 of which have included molecular studies. We present the clinical, radiologic and pathologic findings of an intracranial Ewing sarcoma in a 22-year-old woman arising from the dura over the right frontal convexity. The patient underwent craniotomy with gross total excision of the tumor. The tumor showed atypical histology and 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)(q24;q12) translocation by reverse transcription-polymerase chain reaction. Additional features were detected in this tumor that are known to be associated with an unfavorable prognosis, including loss of p16 expression and gains of chromosomes 1q and 12. The patient experienced the most rapid downhill course reported to date for intracranial Ewing sarcoma, developing multiple extracranial metastases at 2 months and dying 6 months after the initial operation.

Primary Ewing sarcoma/peripheral primitive neuroectodermal tumor of the vulva

We report a case of Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) arising in the vulva in a 17-year-old adolescent girl. Primary extraskeletal ES/pPNET is uncommon and only rarely affects the female genital tract. Characteristic histologic features of ES/pPNET were present in this case including a monomorphic population of small round blue cells with cytoplasmic glycogen confirmed by periodic acid-Schiff and were immunohistochemically positive for CD99 in a membranous and Fli-1 in a nuclear pattern. The presence of an EWS/Fli-1 fusion transcript was demonstrated by reverse transcription polymerase chain reaction and confirmed by direct sequencing. This report described another very rare case of ES/pPNET arising in the vulva and confirmed by molecular analysis.

A 15‐YEAR‐OLD FEMALE WITH PROGRESSIVE MYELOPATHY

March 2005. A 15-year-old female presented with urinary retention, inability to walk and low back pain. MRI disclosed an elongated epidural mass in the thoracic spine with cord compression and invasion into the surrounding bone and soft tissue. Cytologic preparation at intraoperative consultation disclosed a rather monotonous small tumor cells with hyperchromatic nuclei and vacuolated cytoplasm. These vacuoles were best visualized with DiffQuick stain. Pathologic studies revealed an Ewing sarcoma/peripheral primitive neuroectodermal tumor (EWS/pPNET) with typical features including periodic acid Schiff positive diastase sensitive cytoplasmic substance; strong membranous pattern of immunoreactivity for CD99, and a reciprocal translocation of t(11;22)(q24;q12) that was demonstrated by fluorescent in situ hybridization (FISH). The vacuolated cytoplasm was produced by glycogen as demonstrated by electron microscopy. Although primary vertebral EWS/pPNETs are uncommon, they should be considered in the differential diagnoses of extradural/epidural mass of the spine in young patients.

Diagnostic significance and clinical application of specific chimeric genes in soft tissue sarcomas by RT-PCR using paraffin-embedded tissues: a study of 103 specimens

To investigate the expression of the chimeric genes resulting from the specific chromosomal translocations in soft tissue sarcomas (STS) and its diagnostic significance for STS. The variety of fusion transcripts were detected in 103 cases of STS, including 30 cases of synovial sarcoma (SS), 15 cases of rhabdomyosarcoma (RMS), 25 cases of Ewing's sarcoma/peripheral primitive neuroectodermal tumors (ES/pPNET), 12 cases of dermatofibrosarcoma protuberans (DFSP), 14 cases of aveolar soft part sarcoma (ASPS), 3 cases of leiomyosarcoma (LMS), 2 cases of malignant fibrous histocytoma (MFH), and 2 cases of fibrosarcoma (FS); and 20 cases of control tumors by reverse transcription-polymerase chain reaction (RT-PCR) using formalin fixed, paraffin embedded specimens. Of the 34 cases of SS 28 (93.3%) expressed SSX-SYT chimeric transcripts (14 were positive for SYT-SSX1, 9 for SYT-SSX2). Four of the six cases of alveolar RMS had a PAX3/PAX7-FKHR fusion transcript. None of the 9 cases of embryonic and polymorphic RMS expressed PAX3/PAX7-FKHR. Of the 25 cases of ES/pPNET, 19 were positive for EWS-FLI1 fusion transcript and 1 for EWS-ERG fusion transcript. COL1A1-PDGFB fusion transcript was expressed in 8 of the 12 cases (66.7%) of DFSP. Of the fourteen cases of ASPS, ten expressed ASPL-TFE3 fusion transcript. None of the 3 cases of LMS, 2 cases of MFH, 2 cases of FS, and 20 control cases contained any of the fusion transcript. Chimeric gene transcript resulting from specific chromosomal translocations is a reliable index for the molecular diagnosis of STS and RT-PCR assay for detection of specific fusion gene provides a useful tool for confirmation of the diagnosis of STS in diagnostically difficult cases and in retrospective studies.

Detection of EWS-FLI1 fusion transcript in Ewing's sarcoma/peripheral primitive neuroectodermal tumors by one-step RT-PCR using paraffin-embedded tissues

To investigate the expression of EWS-FLI1/ERG fusion transcript resulting from t(11;12)(q24;12) in paraffin-embedded tissues and its diagnostic implication for Ewing's sarcoma/peripheral primitive neuroectodermal tumors (ES/pPNET). One-step reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to detect a characteristic EWS-FLI1/ERG fusion transcript in 25 cases of ES/pPNET and 15 cases of other small round cell tumors (including 8 cases of rhabdomyosarcoma, 4 cases of synovial sarcoma, 2 cases of neuroblastoma and 1 case of lymphoma) using formalin-fixed and paraffin-embedded tissues. EWS-FLI1/ERG fusion transcript was detected in 20 of the 25 ES/pPNET cases (80%). The 15 non-ES/pPNET control cases were negative for EWS-FLI1/ERG fusion transcript. Detection of EWS-FLI1/ERG fusion transcript is a reliable index for molecular diagnosis of ES/pPNET. One-step RT-PCR is a practical method for such analysis in routine paraffin-embedded tumor tissues.

Performance characteristics of a reverse transcriptase-polymerase chain reaction assay for the detection of tumor-specific fusion transcripts from archival tissue.

Pediatric small round cell tumors still pose tremendous diagnostic problems. In difficult cases, the ability to detect tumor-specific gene fusion transcripts for several of these neoplasms, including Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/PNET), synovial sarcoma (SS), alveolar rhabdomyosarcoma (ARMS), and desmoplastic small round cell tumor (DSRCT) using reverse transcriptase-polymerase chain reaction (RT-PCR), can be extremely helpful. Few studies to date, however, have systematically examined several different tumor types for the presence of multiple different fusion transcripts in order to determine the specificity and sensitivity of the RT-PCR method, and no study has addressed this issue for formalin-fixed material. The objectives of this study were to address the specificity, sensitivity, and practicality of such an assay applied strictly to formalin-fixed tissue blocks. Our results demonstrate that, for these tumors, the overall sensitivity for detecting each fusion transcript is similar to that reported in the literature for RT-PCR on fresh or formalin-fixed tissues. The specificity of the assay is very high, being essentially 100% for each primer pair when interpreting the results from visual inspection of agarose gels. However, when these same agarose gels were examined using Southern blotting, a small number of tumors also yielded reproducibly detectable weak signals for unexpected fusion products, in addition to a strong signal for the expected fusion product. Fluorescence in situ hybridization (FISH) studies in one such case indicated that a rearrangement that would account for the unexpected fusion was not present, while another case was equivocal. The overall specificity for each primer pair used in this assay ranged from 94 to 100%. Therefore, RT-PCR using formalin-fixed paraffin-embedded tissue sections can be used to detect chimeric transcripts as a reliable, highly sensitive, and highly specific diagnostic assay. However, we strongly suggest that the final interpretation of the results from this assay be viewed in light of the other features of the case, including clinical history, histology, and immunohistochemistry, by the diagnostic pathologist. Additional studies such as FISH may be useful in clarifying the nature of equivocal or unexpected results.

Primary Cutaneous Ewing??s Sarcoma/Peripheral Primitive Neuroectodermal Tumors in Childhood

Childhood cutaneous and subcutaneous malignancies are rare and include metastatic tumors of diverse histogenesis as well as primary lesions, such as sweat gland carcinomas. Some cutaneous malignancies exhibit a small round cell tumor morphology with few definitive differentiating features; they can thus pose a significant diagnostic problem. We describe two primary malignancies of the skin and superficial subcutis, which were originally diagnosed as sweat gland carcinomas on the basis of their morphological features. A cytogenetic analysis performed on one of these lesions showed the t(11;22)(q24;q12) rearrangement, believed to be unique to the Ewing's sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) group of neoplasms. In view of this unexpected result, reverse transcriptase-polymerase chain reaction analysis was performed on both lesions and showed that they expressed EWS/FLI-1 fusion gene mRNA transcripts, the molecular equivalent of t(11;22)(q24;q12). The two tumors also had an immunohistochemical profile suggesting ES/pPNET, including strong expression of the MIC2 antigen. Both patients were treated with wide local excision, and one was given a course of chemotherapy. Neither patient showed evidence of tumor elsewhere after follow-up periods of 2 years and 16 years. These findings suggest that these tumors are indeed a form of primary ES/pPNET arising in the skin or superficial subcutis, which may be of low-grade malignancy and curable by local surgery.