Primitive neuroectodermal tumor and Ewing's sarcoma

Peripheral primitive neuroectodermal tumor of the orbit in Graves' ophthalmopathy - A rare presentation

Graves' ophthalmopathy is the most common cause of both unilateral and bilateral proptoses in adults. Peripheral primitive neuroectodermal tumor (pPNET) is a small round cell malignant lesion of neuroectodermal origin which very rarely affects the orbit. In this case report, we have discussed about a young woman with existing Graves' ophthalmopathy who presented with worsening proptosis; computed tomography imaging revealed an irregular mass lesion in the right orbit without bone erosion. Biopsy and immunohistochemistry of the mass lesion revealed features of primitive neuroectodermal tumor (PNET). The tumor was MIC-2 gene positive, and on follow-up, no recurrence was noted after successful surgical resection. PNET of the orbit is very rare, and to our best knowledge, this is the first case of peripheral PNET in patent with Graves' ophthalmopathy.

Modeling human telencephalic development and autism-associated SHANK3 deficiency using organoids generated from single neural rosettes

Human telencephalon is an evolutionarily advanced brain structure associated with many uniquely human behaviors and disorders. However, cell lineages and molecular pathways implicated in human telencephalic development remain largely unknown. We produce human telencephalic organoids from stem cell-derived single neural rosettes and investigate telencephalic development under normal and pathological conditions. We show that single neural rosette-derived organoids contain pallial and subpallial neural progenitors, excitatory and inhibitory neurons, as well as macroglial and periendothelial cells, and exhibit predictable organization and cytoarchitecture. We comprehensively characterize the properties of neurons in SNR-derived organoids and identify transcriptional programs associated with the specification of excitatory and inhibitory neural lineages from a common pool of NPs early in telencephalic development. We also demonstrate that neurons in organoids with a hemizygous deletion of an autism- and intellectual disability-associated gene SHANK3 exhibit intrinsic and excitatory synaptic deficits and impaired expression of several clustered protocadherins. Collectively, this study validates SNR-derived organoids as a reliable model for studying human telencephalic cortico-striatal development and identifies intrinsic, synaptic, and clustered protocadherin expression deficits in human telencephalic tissue with SHANK3 hemizygosity.

A rare radiotherapy-sensitive primitive neuroectodermal tumor with APC gene amplification in an adult: a case report and literature review

Primitive neuroectodermal tumor (PNET) of the lung is rare in adults, and treatment options vary. We herein describe the disease course and follow-up of PNET in an adult. A 27-year-old man was admitted to our hospital because of cough and headache, and whole-exome sequencing revealed positive expression of the EWSR1-FLI1 fusion gene and amplification of the APC gene. Although the patient received multidisciplinary treatment including chemotherapy regimens of etoposide plus cisplatin; focal radiotherapy focusing on the cerebrum, lung, and kidneys; and a subsequent palliative gastrointestinal operation, he eventually died of multiple organ functional failure. His overall survival period was 18 months, and his progression-free survival period was 4 months. During the treatment, the patient showed remarkable sensitivity to radiotherapy. In conclusion, PNET of the lung in adult patients is extremely rare, and the prognosis is very poor. Involvement of a multidisciplinary team in the development of personalized therapeutic strategies is essential. This patient with APC gene amplification showed excellent sensitivity to radiotherapy for intrapulmonary and intracranial lesions, suggesting that APC gene amplification may be related to radiotherapy sensitivity. However, further clinical research is needed.

Imaging Findings of Hepatic Ewing's Sarcoma on Computed Tomography and Gadobenate Dimeglumine-enhanced Magnetic Resonance Imaging: A Case Report and Literature Review

Ewing's sarcoma (ES) is a tumor that often occurs in the long bones and rarely arises from visceral organs primarily. Here, we report a case of primary hepatic ES, discuss its computed tomography (CT) and gadobenate dimeglumine-enhanced magnetic resonance (MRI) features. This is the first Chinese and fifth primary hepatic ES case reported, based on a literature review. Imaging examinations showed that the tumor was solid, with necrosis and hemorrhage. Contrast-enhanced images showed that the tumor was hypervascular and especially had heterogeneous signal intensity on hepatobiliary phase MRI images. Intratumoral vessels and vascular invasion were also present.

A challenging diagnosis: Lesson from case series of sacral Ewing sarcoma

Background

Ewing's sarcoma is an aggressive bone and the surrounding soft tissue cancer primarily found in children and young adults. It is mostly observed in the trunk and long bones while unusually seen in the sacrum. Sacral Ewing sarcoma has a unique anatomic limitation due to neurological structures, vertebral column, and pelvic involvement. Hence, identifying sacral Ewing's sarcoma remains a challenge.

Method

This is a case series including three patients diagnosed with Sacral Ewing's sarcoma. These three cases have been diagnosed based on clinical and radiographic examination, MRI, histopathology, and immunohistochemistry examination.

Discussion

Sacral Ewing's sarcoma remains a challenge to diagnose due to its unique anatomy site. MRI examination is sensitive to detect lesions but nonspecific. Thus, require histopathological confirmation.

Conclusion

Early diagnosis of Ewing's sarcoma is essential and we need to perform further examinations, such as immunohistochemistry examination, to confirm the diagnosis of Ewing's sarcoma.

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Sacral Ewing's sarcoma remains a challenge to diagnose due to its unique anatomy site.

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MRI examination is sensitive to detect lesions but nonspecific.

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We recommended to perform further examinations, such as immunohistochemistry examination, to confirm the diagnosis of Ewing’s sarcoma.

Congenital primary primitive neuroectodermal tumor of the orbit in a newborn

INTRODUCTION

Primitive neuroectodermal tumors arise from the progenitor cells of the neural crest, in the central nervous system or other peripheral locations.

CASE PRESENTATION

We report a rare case of a congenital malignant tumor, diagnosed as a primary orbital primitive neuroectodermal tumor on histopathological examination.

CONCLUSION

Multidisciplinary management with adjuvant chemotherapy needed for the management of these cases.

Primitive neuroectodermal tumor incidence, treatment patterns, and outcome: An analysis of the National Cancer Database

BACKGROUND

Primitive neuroectodermal tumors (PNETs) comprise less than 1% of all sarcomas. The rarity of this disease has resulted in a paucity of information about disease process and management. This study sought to evaluate the incidence, treatment patterns, and outcomes among patients with PNET.

METHODS

The National Cancer Database was queried for diagnoses of PNET between 2004 and 2014. Patients were dichotomized based on tumor type (central [cPNET] vs peripheral [pPNET]). Demographic, tumor, treatment, and outcome variables were analyzed for the entire patient cohort and by type of PNET.

RESULTS

White (86.4%) males (56.6%) represented the majority of patients. The incidence of PNET remained stable over the study period (r²  = 0.0821). A total of 70.7% underwent surgical resection of the primary site, 50.3% received radiation, and 74.7% received systemic chemotherapy. Compared to those with pPNET, patients with cPNET more often received radiation treatment (P < .001), primary tumor resection (P < .001), and experienced increased 90-day mortality (P < .014).

CONCLUSION

cPNET and pPNET are rare and aggressive malignancies that tend to arise in White males. Multimodal treatment including surgery, chemotherapy, and radiation is conventional. Patients with cPNET more often receive radiation and primary tumor resection with increased 90-day mortality.

A case report of neonatal orbital peripheral primitive neuroectodermal tumor and literature review

Primitive neuroectodermal tumors are rare malignant neoplasms from primitive neural crest cells. Most primitive neuroectodermal tumors occur in the central and sympathetic nervous systems. We report a Chinese newborn patient presenting a huge unilateral proptosis after birth, diagnosed as orbital peripheral primitive neuroectodermal tumor by histopathology and immunohistochemistry. Our case is the first reported case of orbital peripheral primitive neuroectodermal tumor diagnosed in the newborn period. The clinical manifestations, radiological findings, histopathologic, and immunohistochemistry results are described in detail. We also conducted a literature search focusing on primitive neuroectodermal tumor of the orbit. To the best of our knowledge, all articles with English abstracts were reviewed here.

Extraskeletal Ewing's sarcoma/peripheral primitive neuroectodermal tumor of the small bowel presenting with gastrointestinal perforation

Extraskeletal Ewing’s sarcoma (E-EWS)/peripheral primitive neuroectodermal tumor (pPNET) is a rare soft tissue tumor that arises from a multipotent progenitor cell and is considered to be of neuroectodermal origin. Although soft tissue E-EWS/pPNETs are common, they are exceedingly rare in the small bowel. Only 30 cases of E-EWS/pPNET of the small bowel have been reported. However, only one case of gastrointestinal perforation has been reported till today. Here, we report the second case of E- EWS/pPNET with gastrointestinal perforation.

Renal primitive neuroectodermal tumor with elevated plasma adrenocorticotropic hormone levels: A case report

Introduction

Primitive neuroectodermal tumors are small round‐cell tumors – Ewing sarcoma family, frequently occurring in the extremities, but rarely in the kidney.

Case presentation

A 58‐year‐old woman presented with whole‐body edema and weakness of lower limb muscles. Computed tomography revealed a left renal tumor, and the plasma adrenocorticotropic hormone level was elevated. The tumor was surgically removed without complications, her plasma adrenocorticotropic hormone reverted to normal levels, and symptoms disappeared after surgery. Histopathological examination revealed a primitive neuroectodermal tumor arising in her kidney. The patient was alive without metastasis 3 years after the surgery.

Conclusion

We report the first case of renal primitive neuroectodermal tumor accompanying elevated plasma adrenocorticotropic hormone levels which are thought to be produced and secreted in an ectopic fashion.

Colonic Ewing Sarcoma/PNET associated with liver metastases: A systematic review and case report

Ewing Sarcoma is a highly lethal undifferentiated tumor of bone. ES is a small round cell tumor with etiological and characteristic chromosomal translocations between TET/FET (TLS/FUS, EWSR1, and TAF15) and ETS (E26 transformation-specific) family genes. Generally, therapeutic approach for metastatic Ewing Sarcoma includes both local (surgery and radiotherapy) and systemic (chemotherapy) disease control with an overall cure rate of 20%. For extra-osseous tumors, the most common primary sites of disease are trunk, extremities, head and neck, retroperitoneum. Among other sites, Ewing Sarcoma/PNET may also rarely arise in colon and rectum. Even if colonic Ewing Sarcoma/PNET have been previously reported in 5 cases, none of those reports came from right side of the colon. In this article, we report the first case of right-sided Ewing Sarcoma with synchronous liver metastases completely responding to first line chemotherapy. Furthermore, we provide a systematic qualitative review of the current literature on adult colorectal Ewing Sarcoma using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Comparison of clinical features and outcomes in patients with extraskeletal vs skeletal Ewing sarcoma: an SEER database analysis of 3,178 cases

Background

The clinicopathological characteristics, outcomes and prognostic factors of primary extraskeletal Ewing sarcoma (EES) remained insufficiently explored. We aimed to examine these aspects and compared the same with skeletal Ewing sarcoma (SES).

Patients and methods

We identified Ewing sarcoma, peripheral primitive neuroectodermal tumors or Askin tumor patients who were registered in the Surveillance, Epidemiology, and End Results database from 1973 to 2014. Clinicopathological features were assessed by using Fisher’s exact tests. Cancer-specific survival (CSS) and overall survival (OS) were estimated by using the Kaplan–Meier method and the Cox proportional hazards model. Prognostic factors were identified by multivariate Cox regression analysis.

Results

The age of patients with EES was diagnosed to be higher and they were more likely to be female (46.1% vs 36.2%; P<0.001), have tumor <10 cm (49.8% vs 35.4%; P<0.001), have regional node involvement (5.4% vs 1.0%; P<0.001) and receive surgery (69.1% vs 53.8%; P<0.001) compared to patients with skeletal tumors. Metastatic status did not differ by origin. Kaplan–Meier analysis showed that the origin had significant difference in CSS and OS among patients aged 0–19 years and with metastatic stage at presentation, but not in patients aged 20–39, ≥40 years and with no-metastatic stage. A Cox multivariable model controlling for differences between groups confirmed inferior survival for patients with EES. Age, tumor size, tumor stage and surgery were the most important factors significantly influencing both CSS and OS in the EES and SES patients. Race, year of diagnosis and tumor site were associated with CSS and OS among patients with SES, but failed in EES.

Conclusion

The clinicopathological characteristics, outcomes and prognostic factors differed among patients with EES compared to patients with SES. Extraskeletal origin was an unfavorable prognostic factor.

Diagnostic histochemistry of soft tissue lesions

Histochemical methods (HM) were, at one time, extensively used in all facets of anatomic pathology, including analysis of soft tissue lesions. That situation has changed with the advent of other adjunctive procedures, but HM still do contribute meaningfully to the evaluation of several tumefactive conditions in the soft tissue. This brief review considers selected neoplastic, quasineoplastic, and pseudoneoplastic lesions in that category, with emphasis on their histochemical properties.

Ewing's Sarcoma/Peripheral Primitive Neuroectodermal Tumors in Bronchus

Ewing sarcoma/peripheral primitive neuroectodermal tumors (ES/pPNET), a member of the Ewing sarcoma family of tumors, is a malignant soft tissue tumor with small undifferentiated neuroectodermal cells. Primary trachea-bronchial ES/pPNET is very rare. The most common pulmonary ES is due to a metastasis. We describe a case of ES/pPNET which originated in the left basal trunk bronchus. The patient was a 30-year-old male, presenting with irritable cough and fever for 10 days. A tumor of 60 mm in diameter was found in the left basal trunk bronchus, extending to the left lower lobe. No distant metastases were detected. Histopathological examination revealed a malignancy of ES/pPNET with a diffuse proliferation of round cells, a Flexner-Wintersteiner rosette formation and positive staining for CD99. The patient was successfully treated with a combination of left lower lobectomy and adjuvant chemotherapy and has remained disease-free for approximately 18 months at follow-up. This case highlights that ES/pPNET should be considered as a differential diagnosis in cases of trachea-bronchial tumors.

MR Imaging of Primary Chest Wall Neoplasms

Primary chest wall neoplasms are uncommon and comprise a heterogeneous group of lesions that may be challenging to classify and diagnose. These tumors may be primary or secondary, malignant or benign, and arise from cartilaginous/osseous structures or soft tissues. The role of magnetic resonance (MR) imaging in the evaluation of chest wall tumors continues to expand given its superior soft tissue contrast relative to computed tomography. MR imaging can facilitate differentiation of neoplasms from normal chest wall structures and other disease processes due to infection and inflammation, and can fully characterize abnormalities by demonstrating the various internal components of complex lesions. It is important that radiologists be able to identify key features of primary chest wall neoplasms on MR imaging to provide focused differential diagnoses and guide patient management.

Sarcoma With CIC-DUX4 Gene Fusion: Case Report of Kidney Tumor Location in a 12-year-old Boy

Recent molecular advances have identified a novel sarcoma defined molecularly by oncogenic fusion of the genes CIC and DUX4 termed CIC-DUX4 sarcomas. The most common site of involvement was the trunk but some cases have been described in the head and neck and extremities. We report one of the first cases of primitive renal CIC-DUX4 sarcoma: a 12-year-old boy who presented a renal tumor, a vena cava thrombus, and lung metastases. The morphological and immunohistochemical analysis showed an undifferentiated sarcoma. Molecular analysis demonstrated a CIC-DUX4 translocation, confirmed by fluorescence in situ hybridization. Despite treatment with chemotherapy, the evolution was unfavorable and the patient died 17 months after the diagnosis in a context of brain metastases. The diagnosis of sarcoma with CIC-DUX4 gene fusion is difficult in lack of specific pathological characteristics emphasizing the need for molecular analysis. Treatment has not yet been codified for these very aggressive tumors.

Primary primitive neuroectodermal tumor of the kidney

Renal primitive neuroectodermal tumor (PNET) is a rare entity. It should be differentiated from other primary renal malignancies. The differentiation of the malignant small round cell tumors may be challenging; however, it is essential for better management of the patient. We report a 45-year-old male having complaints of pain in the abdomen, hematuria, and mass in the abdomen for 6 months. Abdominal and pelvic sonography finding showed cystic-solid, right renal mass suggestive of malignancy. On histopathology diagnosed as malignant small round blue cell tumor suggestive of primitive neuroectodermal tumor. On immunohistochemistry, CD99 positivity confirmed the diagnosis of primary PNET of the kidney. We are presenting this case for its rarity, clinical presentation, and pathological findings.

Retrospective Analysis of Ploidy in Primary Osseous and Extraosseous Ewing Family Tumors in Children

Aims

To restrospectively study the DNA content in a series of childhood Ewing Family Tumors (EFT), and to investigate its prognostic value.

Methods

The study was performed on a series of 27 EFTs (osseous Ewing's sarcoma, 18 cases; extraos-sous Ewing's sarcoma, 2; peripheral neuroepithelioma, 4; Askin Rosai tumors, 3). Ploidy was investigated using both flow cytometry (FCM) and image cytometry (ICM) on tumor cell suspensions from formalin-fixed paraffin-embedded specimens or fresh frozen tissue obtained from the primary tumor at diagnosis.

Results

Ploidy was evaluable by FCM in all cases, and by ICM in 23/27. When fresh frozen tissue and paraffin-embedded samples from the same tumor were available for analysis, they yielded equal results. The rate of agreement between FCM and ICM was 82%. The majority of cases were diploid, and in the present series aneuploidy seemed to be associated with a poor outcome.

Conclusions

These results suggest that aneuploidy could be an indicator of a bad prognosis in EFT; however, the small number of cases precludes any conclusion of statistical value. Larger restrospective studies on ploidy using archival material could be performed and their reliability is supported by the concordance of results from fresh and formalin-fixed tissue.

Histologic Features and Prognosis of Spinal Intradural Extramedullary Ewing Sarcoma: Case Report, Literature Review, and Analysis of Prognosis

BACKGROUND

Ewing sarcoma is a malignant neoplasm that primarily involves extremity long bones, the pelvis, and soft tissues of children. The intradural extramedullary space is an uncommon location for Ewing sarcoma, and there is therefore a paucity of information regarding the features and natural history of this particular presentation. There is controversy regarding preoperative diagnosis, surgical management, and postoperative care, and there are no accepted standards.

METHODS

Herein we present a 61-year-old man with an L1-3 intradural extramedullary Ewing sarcoma who underwent gross total resection of the tumor via laminectomy. Pathologic analysis revealed a diagnosis of Ewing sarcoma based on the characteristic immunohistochemistry and the presence of EWSR1-FLI1 fusion transcript by reverse-transcription polymerase chain reaction.

RESULTS

There have been 28 cases of intradural extramedullary Ewing sarcoma reported in the literature. Out of 29 cases including the current case, 18 cases (62.1%) were men. The median and mean ages were 32 and 34.0 years, respectively, with a peak age group of 10-20 years. Twenty-two of 29 (72.4%) cases involved the lumbar spine, followed by the cervical spine (n = 7, 24.1%). Long-term prognosis was poor, with 1-, 2-, 3-, and 5-year progression-free survival rate of 75.0%, 56.3%, 37.5%, and 18.8%, respectively. The 1-, 2-, 3-, and 5-year overall survival rate was 89.5%, 80.5%, 80.5%, and 43.0%, respectively.

CONCLUSIONS

Herein, we present imaging and pathologic findings of the case with review of the literature.

Pediatric Orbital Primitive Neuroectodermal Tumors

PURPOSE

To present the clinical, radiological, histopathological, immunohistochemical features and the follow-up of orbital primitive neuroectodermal tumors (PNETs) in pediatric patients along with a review of the literature.

METHODS

A retrospective analysis of all diagnosed cases of orbital PNET was done. Patients' ophthalmic findings, imaging, immunohistochemistry, metastatic work-up, treatment, globe salvation, and survival were documented and a mini literature review of orbital PNET was performed.

RESULTS

Four diagnosed cases of orbital PNET presented with proptosis and visual impairment were treated during the study period. The radiological imaging showed primary orbital involvement. There were three males and one female with a mean age of 63.75 months (range: 3 to 244 months). Histopathology of all studied patients showed round malignant cells with hyperchromatic nuclei, increased nuclear cytoplasmic ratio, and positive test results for CD99 and FLI-1. The studied patients underwent orbital surgery for excision of tumors followed by chemotherapy. One of the patients also had external radiation in addition to chemotherapy after a second recurrence. The follow-up period of these patients varied from 1 to 5 years. Only one child who had recurrence twice was followed up to 5 years, but was lost to follow-up after that.

CONCLUSIONS

The authors believe that most orbital peripheral PNET tumors present as well-defined masses on both imaging and perioperatively and are easily removed surgically. The apparently disguised "benign profile" of orbital PNET may prove deceptive and the shorter duration of symptoms remains a strong reminder of the malignant nature of the lesion. [J Pediatr Ophthalmol Strabismus. 2018;55(2):93-99.].

Primary Ewing's sarcoma/primitive neuroectodermal tumor of the ileum: case report of a 16-year-old Chinese female and literature review

Background

Ewing’s sarcoma (ES) and primitive neuroectodermal tumors (PNET) are closely related tumors. Although soft tissue ES/PNET are common in clinical practice, they are rare in the small intestine. Because of the absence of characteristic clinical symptoms, they are easily misdiagnosed as other benign or malignant diseases.

Case presentation

Here, we present the case of a 16-year-old female who complained of anemia and interval hematochezia. Her serum test results showed only a slight elevation of CA-125 and a low level of hemoglobin. Computer tomography and magnetic resonance imaging revealed a cystic and solid mass in the lower abdominal quadrant and pelvic region, which prompted suspicion of a malignant gastrointestinal stromal tumor of the small intestine. After resection, the tumor’s histology and immunohistochemistry (positive for CD99, vimentin and synaptophysin) results suggested ES/PNET. Fluorescent in situ hybridization tests proved the breakpoint rearrangement of the EWSR1 gene in chr 22.Ultrastructural analysis revealed neurosecretory and glycogen granules in the tumor cell cytoplasm.

Conclusions

Together, these data supported the diagnosis of a rare case of localized ES/PNET in the small intestine without adjuvant chemo- or radiotherapy. To our knowledge, this is the first report from China of a primary small bowel ES/PNET in the English-language literature. In addition, on the basis of findings from previous publications and the current case, the optimal treatment for localized gastrointestinal ES/PNET is discussed.

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.

Pulmonary and pleural pathology: Contributions of Dr. Louis "Pepper" Dehner

Dr. Louis Dehner is an internationally renowned surgical pathologist who has published multiple textbooks and has authored or co-authored nearly 400 original articles in the medical literature. While many think of him as a pediatric pathologist, he has contributed to the literature across virtually the entire breadth of surgical pathology, and the lung and pleura is no exception. This review will highlight Dr. Dehner׳s contributions to the pulmonary and pleural pathology literature in the areas of infectious disease, medical lung disease and transplant pathology, and a number of neoplasms of the lung and pleura, with the remainder of this manuscript dedicated to the still evolving story of the pleuropulmonary blastoma as the signature contribution of his long and distinguished career.

Pediatric soft tissue tumor pathology: A happy morpho-molecular union

Since its foundation by remarkably talented and insightful individuals, prominently including Pepper Dehner, pediatric soft tissue tumor pathology has developed at an immense rate. The morphologic classification of tumoral entities has extensively been corroborated, but has also evolved with refinement or realignment of these classifications, through accruing molecular data, with many derivative ancillary diagnostic assays now already well-established. Tumors of unclear histogenesis, classically morphologically undifferentiated, are prominent amongst pediatric sarcomas, however, the classes of undifferentiated round- or spindle-cell-tumors-not-otherwise-specified are being dismantled gradually with the identification of their molecular underpinnings. Within recent years, for example, numerous subcategories of 'Ewing-like' round cell sarcoma have emerged. Such advances have provided the basis for novel diagnostic and prognostic sub-classifications. Efforts at defining cell- or lineage-of-origin for several tumor types have produced interesting insights especially for rhabdomyosarcoma. The remarkably early onset of pediatric sarcomas defies the theory necessitating stochastic accumulation of several somatic mutations for cancer development and indeed, these tumors may be remarkably genomically stable, often belying their aggressive nature. Much is coming to light recently regarding the role of epigenetic modifications in the evolution of these sarcomas. Indeed the morphologic features of embryonal tumors generally (not just sarcomas) may be highly reminiscent of arrested differentiation, and given the tight epigenetic regulation of cell fate determination and cell identity maintenance, a theory of epigenetically-driven oncogenesis sits easily with these tumors. The age-delimited distinct biologies of 'pediatric' and adult GIST are intriguing, particularly, the SDH-deficient 'pediatric' form, driven by a metabolic defect, but resulting in epigenetic dysregulation with genome-wide DNA methylation changes. There is little doubt that many of the gaps in our understanding of pediatric sarcoma biology will be filled by a deeper appreciation of the role of dysregulated epigenetics including chromatin biology, perhaps best exemplified in malignant rhabdoid tumor. The field of pediatric soft tissue tumor pathology grows ever more interesting. Importantly though, it must be emphasized, that none of this progress could have occurred, or indeed continue, without the initial step of accurate diagnosis, founded solidly on morphology - thank you Pepper for your unparalleled contributions to this field! The opportunity to be your apprentice for five years has been a bigger and more positive influence than words can express.

Imaging Evaluation of Malignant Chest Wall Neoplasms

Neoplasms of the chest wall are uncommon lesions that represent approximately 5% of all thoracic malignancies. These tumors comprise a heterogeneous group of neoplasms that may arise from osseous structures or soft tissues, and they may be malignant or benign. More than 50% of chest wall neoplasms are malignancies and include tumors that may arise as primary malignancies or secondarily involve the chest wall by way of direct invasion or metastasis from intrathoracic or extrathoracic neoplasms. Although 20% of chest wall tumors may be detected at chest radiography, chest wall malignancies are best evaluated with cross-sectional imaging, principally multidetector computed tomography (CT) and magnetic resonance (MR) imaging, each of which has distinct strengths and limitations. Multidetector CT is optimal for depicting bone, muscle, and vascular structures, whereas MR imaging renders superior soft-tissue contrast and spatial resolution and is better for delineating the full extent of disease. Fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT is not routinely performed to evaluate chest wall malignancies. The primary functions of PET/CT in this setting include staging of disease, evaluation of treatment response, and detection of recurrent disease. Ultrasonography has a limited role in the evaluation and characterization of superficial chest wall lesions; however, it can be used to guide biopsy and has been shown to depict chest wall invasion by lung cancer more accurately than CT. It is important that radiologists be able to identify the key multidetector CT and MR imaging features that can be used to differentiate malignant from benign chest lesions, suggest specific histologic tumor types, and ultimately guide patient treatment. (©)RSNA, 2016.

Ewing's Sarcoma and Peripheral Primitive Neuroectodermal Tumor of Bone and Soft Tissue

The histological diagnosis of Ewing's sarcoma (Es) continues to be a difficult task for pathologists. A number of new Es varieties has been described, leading to further complexity. Conventional Es, atypical Es, and peripheral neuroectodermal tumor (pPNET), including peripheral neuroepithelioma, belong genetically to the same family of neoplasms, displaying common chromosomal rearrangements and analogous gene reorganizations. The main translocations are t(11;22) and t(21;22), with genes EWS, FLI-1 and ERG being involved, as well as other members of the ETS family of transcription factors. The prevalence of morphology should be maintained with the use of conventional histological techniques and supported with the analysis of the expression of CD99 Mic2 (HBA 71, 0.13) antigen, which is present in over 90% of cases, as well as with FLI-1 rearranged gene derived protein. Moreover, FISH and RT-PCR in paraffin-embedded tumor tissue may be of use in extremely difficult cases for differential diagnosis. Nevertheless, a number of mixed tumor types, such as primitive sarcoma or biphenotypic sarcoma, may show structural and genetic diversity, thus rendering their diagnosis even more complex.

Peripheral Neuroectodermal Tumor-Ewing's Sarcoma of the Thumb With Local Recurrences and Pleural Metastases After 17 Years

We report a case of an 8-year-old boy who initially presented with a painful subungual mass that was diagnosed as a "glomus tumor" largely based on the clinical presenta tion. Local excision was performed, and the patient remained tumor free for 17 years, after which he experienced three local recurrences and massive pleural metastases within the next 2 years. The tumor was poorly differentiated with small round cells and increased mitotic activity on light microscopy. The precise nature of the tumor was difficult to characterize and was unraveled primarily by immunoperoxidase studies, particularly the diffuse strong positivity of HBA-71 (MIC 2) antibody, also called pe ripheral neuroectodermal tumor-Ewing's sarcoma antigen, which is reported to be fairly specific for these tumors, and the expression of neural markers Leu-7 (HNK-1 ) and neuron-specific enolase. In addition, ultrastructural examination revealed imma ture cell junctions, cell processes, and abundant pools of intracytoplasmic glycogen. Metastatic pleural tumor recurred very rapidly after excision, but showed a dramatic, although short-lasting, response to chemotherapy with cisplatin and etoposide. The thumb is an uncommon location for peripheral neuroectodermal tumor-Ewing's sar coma, and a 17-year, disease-free interval is most unusual for a malignant tumor of this nature. We discuss this case with respect to its unique clinical behavior and in the context of the differential diagnosis of small, round cell neoplasms. Int J Surg Pathol 2(2):147-156, 1994

Exenteration and Custom Implant Brachytherapy as a Treatment for Recurrent Primary Extraskeletal Orbital Ewing Sarcoma

A 6-year-old boy initially presented to an outside hospital with a right orbital mass with biopsy positive for translocation involving EWS RNA-binding protein 1 gene and imaging consistent with primary extraskeletal Ewing sarcoma (ES). There was no evidence of metastatic disease. Patient underwent gross tumor resection and adjuvant chemotherapy (VAdriaC/IE) followed by postoperative 45-Gy proton beam radiation. After 19 months, a solitary in-field local recurrence occurred, which was unsuccessfully surgically resected. Thereafter, treatment commenced with irinotecan and temozolomide, and the patient presented to the center of the authors. MRI showed locally recurrent disease without evidence of metastatic disease. Right orbital exenteration was performed, and an orbital mold was fashioned to deliver brachytherapy. There were no complications. The patient had no evidence of recurrent disease at 37-month follow up. This is the first report of orbital implant brachytherapy for recurrent primary ES of the orbit, and an additional report of primary extraskeletal ES of the orbit, which is a rare primary orbital tumor.

Primary Ewing Sarcoma Presenting as a Vulvar Mass in an Adolescent: Case Report and Review of Literature

BACKGROUND

Extraosseous Ewing sarcoma (ES) tumors presenting in the genitourinary tract are highly uncommon. Few cases of primary vulvar and vaginal cases of ES have been published.

CASE

A 15-year-old adolescent presented with a bothersome 5-cm mass located on her left labium minorum. Following excision, a diagnosis of a primary ES was made. The patient was treated with multiagent chemotherapy and was doing well 20 months after treatment completion.

SUMMARY AND CONCLUSION

Based on the few available case reports and our reported case, it appears that extraosseous ES arising in superficial sites such as the vulva have better prognosis and should be treated with complete excision and multiagent chemotherapy.

Peripheral Primitive Neuroectodermal Tumor (pPNET) of the Penis: A Case Report and Literature Review

Primitive neuroectodermal tumors are derived from primitive neuroectodermal cells and belong to a highly malignant subgroup of round-cell tumors. Peripheral primitive neuroectodermal tumors of the penis are an extremely rare malignant form among penile neoplasms. These tumors are often difficult to diagnose due to atypical symptoms. Here, we report a case of a 24-year-old patient in China with a neoplasm localized at the base of his penis. The initial symptom was dysuria without any inducement. The results of blood and urine examinations indicated no abnormalities. The imaging examination results indicated a firm mass near the base of the penis. The hematoxylin and eosin (H&E) staining revealed round, small tumor cells with heterotypical darkened nuclei. In addition, immunohistochemistry (IHC) revealed strong and diffuse positive staining for CD99 (mic-2), VIM (vimentin), and NCAM1/CD56 (neural cell adhesion molecule 1). In addition, 60% of cells were positive for the cell proliferation marker Ki-67. Based on the above results, the case was diagnosed with peripheral primitive neuroectodermal tumor (pPENT). We reviewed the literature from 1999 to 2013 and identified reports of pPENT with a low incidence and atypical symptoms. Accurate diagnosis with multiple detection technologies, including laboratory diagnostic tests, imaging, morphologic and immunologic examinations, is very important to reduce the misdiagnosis rate.

Primary Multiple Pulmonary Primitive Neuroectodermal Tumor: Case Report and Literature Review

Primitive neuroectodermal tumors (PNETs) arising directly from the lung are extremely rare but particularly aggressive neoplasms. Although thoracic PNET usually develops on the chest wall, there have been reports of primary Ewing sarcoma/PNET of the lung.We present the case of a 16-year-old male with PNET diagnosed following histologic and immunohistochemical examination of a video-assisted thoracic surgical biopsy. As typically occurring for these tumors, the diagnosis was initially delayed in our patient and prognosis was poor despite aggressive surgical resection and postoperative chemotherapy. We attempted to explore the use of targeted pharmacotherapy through high-throughput sequencing in this case. We found that this treatment using Avastin and Cetuximab could provide a new therapeutic direction for PNET.PNENTs arising from the lung parenchyma without pleural or chest wall involvement are extremely rare. Although uncommon, if the pathological features are similar to Ewing sarcoma, PNENTs should be kept in mind, and the target therapy may be a potent treatment for this disease.

A note from history: Landmarks in history of cancer, part 7

In the 2 and half decades reviewed (1970-1995), research established that chromosomal translocation, deletion, and DNA amplification are prerequisites to cancerogenesis and that oncogenes, tumor-suppressor genes, growth factors, and cytokines play crucial roles in the pathomechanism of cancer. Human papillomavirus, human immunodeficiency virus, herpes virus, and hepatitis B virus were identified as cancer-causing viruses. Several laboratory tests were developed for the detection of primary and recurrent cancers, and cancer prevention by screening methods was popularized. Sonography, computerized tomography, magnetic resonance imaging, positron emission tomography, excision of sentinel lymph nodes, and immunohistochemical techniques became routine procedures. Clinicopathologic staging and classification of tumors were standardized. Limited surgery, adjuvant and neoadjuvant chemoradiation, and the therapeutic use of monoclonal antibodies, tumor vaccines, and targeted chemotherapy became routine practice. The decline in cancer incidence and mortality demonstrated that cancer prevention and advancement in oncology are pivotal to success in the crusade against cancer. Above all, it was clearly established that the care of patients with cancer can be accomplished best in a multidisciplinary setting involving surgical oncologists, radiologists, radiation therapists, medical oncologists, surgical pathologists, and laboratory scientists. In conclusion, the 25 years from 1970 and 1995 are the high-water mark in clinical oncology, and this is the period when oncology turned from art to science.

Mandibular peripheral primitive neuroectodermal tumor: a rare case report with review of literature

Primitive neuroectodermal tumor (PNET) is a high grade malignant neoplasm of small round cell tumor family, commonly affecting children and young adults. Peripheral primitive neuroectodermal tumor (pPNET) is a predominately neural, nonepithelial malignancy seen outside the nervous system that can arise in any place throughout the body including the diverse tissues of the head and neck. The diagnosis of PNET is confounded by its clinical and histopathological similarity to Ewing's sarcoma of the bone and has seldom been reported in the literature. The paucity of literature pertaining to the successful diagnosis and management of this lesion mandates its documentation and discussion. This article describes a case of an 11-year-old boy with an aggressive pPNET of the mandible. The clinical and radiographic presentations of this rare entity along with a detailed review on the current management modalities have been discussed.

Primary primitive neuroectodermal tumor arising in the mesentery and ileocecum: A report of three cases and review of the literature

Primitive neuroectodermal tumor (PNET) is most commonly encountered in the soft tissue or bone in children and young adults, and its involvement in the intestines is exceedingly rare. To the best of our knowledge, eighteen cases have been reported to date. The present study reports three cases of PNET arising in the mesentery and ileocecum in 59- and 22-year-old males and a 36-year-old female. Computed tomography revealed a solid mass in the lower abdomen, with areas of cystic changes. Microscopically, the tumors were composed of small round cells arranged in sheets and rosettes with scant cytoplasm, hyperchromatic nuclei and a high mitotic rate. The tumor cells were immunopositive for CD99 and FLI1. EWS/FLI1 translocations were detected in all cases. Case 1 and case 2 underwent tumor resection without any preoperative radiotherapy, chemotherapy or biological therapy. Case 3 underwent tumor resection and received eight cycles of IAP chemotherapy (2.0 mg ifosfamide, 80 mg epirubicin, 30 mg cisplatin 30mg). Case 3 was followed up for 34 months until they succumbed to peritoneal recurrence, whereas the other cases were not followed up. The incidence of these small round-cell tumors in the intestinal system, their clinical and pathological features and differential diagnosis are discussed with a review of the literature.

Peripheral primitive neuroectodermal tumor of the parotid gland in a child: A case report

Primitive neuroectodermal tumor (PNET) is a term used to describe a group of highly malignant neoplasms of soft-tissue origin, with varying degrees of divergent differentiation. The occurrence of peripheral PNET in the head and neck region has been reported infrequently in the medical literature. This disease generally occurs in adolescents and young adults, and rarely occurs in children <3 years old. The current study presents an extremely rare case of pPNET of the parotid gland in a 2-year-old male, which had been previously misdiagnosed and treated as a mumps. The lesion showed the characteristic histological features of pleomorphic cellular infiltrate with hyperchromatic small cells scattered in the fibrovascular stroma, interposed by fibrous septa and Homer-Wright rosettes. Positive immunohistochemical staining for CD99 and vimentin was detected. The patient was treated with chemotherapy and radiotherapy following surgical removal, and has been under close observation since the treatment (approximately seven months), with no signs of recurrence. The clinical history and radiological and histopathological findings are presented, together with the immunoreactivity of this tumor.

Ewing's Sarcoma: An Uncommon Breast Tumor

Ewing’s sarcoma/primitive neuroectodermal tumors (EWS/PNET) are rare malignant and aggressive tumors, usually seen in the trunk and lower limbs of children and young adults. They are uncommon in the breast. We report a case of a 43-year-old woman who developed a painless breast mass. An initial core needle biopsy concluded to a fibrocystic dystrophy contrasting with a rapidly growing mass; thus a large lumpectomy was done. Diagnosis of primary PNET of the breast was established, based on both histopathological examination and immunohistochemical findings. Surgical margins were positive, therefore, left modified radical mastectomy with axillary lymph nodes dissection was performed. The patient was given 6 cycles of adjuvant chemotherapy containing cyclophosphamide, adriamycin and vincristine. Twenty months later, she is in life without recurrence or metastasis. EWS/PNET may impose a diagnostic challenge. Indeed, mammography and ultrasonography features are non specific. The histopathological pattern is variable depending on the degree of neuroectodermal differentiation. Immuno-phenotyping is necessary and genetic study is the only confirmatory tool of diagnosis showing a characteristic cytogenetic anomaly; t (11; 22) translocation.

Germ cell tumors of the ovary: an update

CONTEXT

The field of ovarian germ cell tumors (OGCTs) has remained relatively unchanged in the last 2 decades. However, the introduction of new stem cell pluripotency markers has provided a new understanding into the identification and taxonomy of OGCT types. New data have provided new insights into unusual teratoma-associated autoimmune disorders and the origin of gliomatosis peritonei.

OBJECTIVE

To review the impact of new pluripotency markers in the diagnosis of malignant OGCT (MOGCT) and analyze new nomenclature proposals and clinicopathologic entities.

DATA SOURCES

Ovarian germ cell tumors from routine material and expert consultation files at San Cecilio University Hospital, Granada, Spain, and the relevant literature were reviewed.

CONCLUSIONS

Although a correct diagnosis of MOGCT can often be made with histologic and classic immunohistochemical studies, the new immunohistochemical pluripotency markers give higher diagnostic accuracy. Germ cell tumors represent a caricature of the phases of normal embryonic differentiation from primordial germ and stem cells to extraembryonal and somatic tissue differentiation. Since every stage of differentiation and its related tumor type exhibit characteristic markers, the analysis of their expression facilitates tumor typing, thus complementing the use of classic antibodies. They also allow a more precise evaluation of the degree of immaturity in teratoma. The new term, primitive endodermal tumors, simplifies the understanding of the complex histology of the yolk sac tumor group, as this terminology encompasses its multiple endodermal differentiations. Recently described autoimmune encephalitis due to antibodies against the N-methyl-d-aspartate receptor has become the most frequent autoimmune disorder associated with ovarian teratoma.

Primitive neuroectodermal tumor originating in the vulva: A case report

Primitive neuroectodermal tumors (PNETs) exhibit chromosomal translocations in common with those of Ewing’s sarcoma. They usually originate in bone or soft tissue but rarely arise in the vulva. The current case report presents a case of PNET originating in the vulva in a 60-year-old female, who previously underwent enucleation of a vulvar tumor in another hospital. The pathologist suspected a histopathological diagnosis of PNET, and simple vulvectomy and resection of the inguinal lymph nodes were performed. An ~3 cm mass recurred in the right side of the vulva four years following the initial surgery and the tumor was excised. The tumor comprised small, round-to-oval nuclei and stained positively for MIC-2, synaptophysin, neuron-specific enolase and neurofilament antibodies. To date, the patient remains alive and with no evidence of disease four years following multidisciplinary treatment, despite PNETs usually exhibiting a poor prognosis. This is due to the small tumor size and the absence of distant metastasis.

Optimal management of Ewing sarcoma family of tumors: recent developments in systemic therapy

The Ewing sarcoma family of tumors (ESFT) is defined by cell surface expression of CD99 and a translocation involving EWS and an ETS partner. Cytotoxic chemotherapy remains the benchmark of first- and second-line therapy, and although the majority of patients with localized disease are cured, almost one third of patients relapse or progress from their disease. Moreover, cure remains elusive in most patients who present with distant metastases. In recent years, the ESFT literature has been dominated by reports of attempts at modulating the insulin-like growth factor (IGF) receptor (IGFR). Unfortunately, three phase II studies examining inhibiting antibodies to IGFR-1 published disappointing results. Whether these results were due to failure to modulate the pathway or other limitations in study design and/or patient selection remain unclear. Other novel strategies currently being investigated in ESFT include tyrosine kinase, mammalian target of rapamycin (mTOR), and poly(ADP-ribose) polymerase (PARP) inhibitors.

Three cases of a peripheral primitive neuroectodermal tumor diagnosed using computed tomography or magnetic resonance imaging

The present study describes the findings from three cases of peripheral primitive neuroectodermal tumors (PNETs) diagnosed using computed tomography (CT) or magnetic resonance imaging (MRI). The patients were all diagnosed with PNETs of the peripheral central nervous system. All the lesions were soft-tissue masses with cystic degeneration. The CT images revealed that the lesions were large and inhomogeneous, with unclear borders and cystic degeneration. The surrounding tissues and structures were compressed against each other. Following the enhancement of the CT, the solid components of the tumors were enhanced, whereas the cystic components did not show enhancement. Following the enhanced MRI, irregular enhancement was noted in the solid components and the cystic and solid masses showed unclear borders. The surrounding tissues were compressed. The solid components of the tumors were enhanced, whereas the cystic components showed no enhancement. Based on these observations, PNETs were diagnosed. Thus, a CT or MRI is mandatory for the precise diagnosis of a peripheral PNET.

High grade primitive neuroectodermal tumor of the uterus: A case report

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Primitive neuroectodermal tumor of the uterus is extremely rare.

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Diagnosis requires timely evaluation with molecular analysis.

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Different combinations of adjuvant chemotherapy have been reported.