Tumor neuroectodérmico primitivo / Primitive neuroectodermal tumor

El tumor neuroectodérmico primitivo periférico (PPNET) o neuroepitelioma periférico es una neoplasia maligna de células redondas azules pequeñas derivadas de la cresta neural. Es uno de los tipos histológicos más indiferenciados entre los tumores malignos. Por ser indistinguible del sarcoma de Ewing, desde el punto de vista de imagen e histología, se considera una única patología para su estudio. Puede aparecer en la infancia o más frecuente en la adolescencia; el tratamiento incluye quimioterapia, cirugía y radioterapia. Se presenta el caso clínico de un paciente de 77 años de edad que consulta por ptosis palpebral y es catalogado como Síndrome de Horner. El diagnóstico final fue tumor neuroectodérmico periférico confirmado con histopatología e inmunohistoquímica

A primitive neuroectodermal tumor (PPNET) or peripheral neuroepithelioma is a malignant neoplasm of small round blue cells derived from the neural crest. It is one of the most undifferentiated histological types among malignant tumors, because it is indistinguishable from Ewing's sarcoma from the imaging and histology perspective. It considers a single pathology for this paper. It can appear in childhood or more frequently in adolescence; treatment includes chemotherapy, surgery, and radiation therapy. We present the clinical case of a 77 year-old patient who consulted for palpebral ptosis, and it classifies as Horner's Syndrome. The final diagnosis was a peripheral neuroectodermal tumorconfirmed with histopathology and immunohistochemistry.

Cytokeratin-positive primitive neuroectodermal tumor of the prostate: Case report and review of literature.

Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) of the prostate is extremely rare. Here, we report a case of ES/PNET of prostate in a 24-year-old man presenting with dysuria and pelvic discomfort. Computed tomography scan revealed a heterogeneous mass involving the prostate without evidence of distant metastases. Histologically, the tumor was composed of small round blue cells strongly and diffusely positive for CD99 and epithelial markers. Fluorescence in situ hybridization confirmed rearrangement of the Ewing's sarcoma region on chromosome 22.

Tumor neuroectodérmico de seios paranasais: diagnóstico e tratamento / Primitive neuroectodermal tumor of paranasal sinuses: diagnosis and treatment

Tumores neuroectodérmicos primitivos (PNET) são neoplasias raras e extremamente agressivas encontradasprincipalmente em crianças e adultos jovens. São classificados em periféricos ou centrais, de acordo com sua origem. O diagnóstico baseia-se na história clínica, sendo essenciais exames de imagem, como tomografia computadorizada e ressonância magnética, e, para a confirmação, estudo anatomopatológico. É importante distingui-los de outros tumores de células redondas pequenas,como linfoma, sarcoma de Ewing extraósseo e rabdomiossarcoma,exigindo diferenciação imunoistoquímica através de marcadores específicos. O tratamento envolve cirurgia, quimioterapia e radioterapia, sendo o prognóstico pobre e a sobrevida bastante reservada. O objetivo deste artigo é discutir as características clínicas, radiográficas ehistológicas dos tumores neuroectodérmicos primitivos e seu tratamento...

Primitive neuroectodermal tumours (PNET) are rare and highly aggressive neoplasms found mainly in children and young adults. They are classified in peripheral or central according to their origin. The diagnosis is based on clinical history, computed tomography and magnetic resonance imaging, but the pathological study is the only way to confirm it. It´s very important to distinguish the PNET from other small cell round cell tumors - such as lymphoma, Ewing´s sarcoma and rhabdomyosarcoma – through immunohistochemical specific markers. The treatment includes surgical resection, chemotherapy and irradiation. The prognosis is poor and the survival rate is variable. This article aims to discuss the clinical, imagingand histological features of the primitive neuroectodermal tumors and their treatment...

Ewing's Sarcoma of the Lesser Sac Masquerading as a Pancreatic Tumor

Extraosseous Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is an uncommon, aggressive, and malignant tumor with a poor patient outcome. Its occurrence in the lesser sac is a rare event and to the best of our knowledge, has not been previously described. The present case was clinically and radiologically misdiagnosed as a pancreatic tumor/gastrointestinal stromal tumor. Histopathology revealed a tumor with "small round cells" that were positive for CD99, confirming the diagnosis of ES/PNET. This report highlights the importance of considering Ewing's sarcoma in the differential diagnosis of intraabdominal, extraintestinal masses.

Multimodality treatment approach in management of primary peripheral primitive neuroectodermal tumor of the orbit.

Primitive neuroectodermal tumor is a small round cell malignancy which rarely involves the orbit. We report a case of a two-year old male child presenting as unilateral eccentric proptosis with extraconal and intraconal mass, diagnosed as primary peripheral primitive neuroectodermal tumor (pPPNET) on histopathology and immunohistochemistry. There is no defined consensus in the management of these tumors due to its rare presentation. We describe its distinguishing features with emphasis on multimodal and aggressive treatment approach which ensures appropriate management of these cases.

Polyphenotypic peripheral neuroepithelioma occuring in the foot: a case report.

Peripheral neuroepithelioma of the soft tissues is an uncommon member of primitive neuroectodermal tumors. Divergent differentiation and polyphenotypia is known in peripheral neuroepithelioma. We report one such recurrent peripheral neuroepithelioma in an infant which was detected at one month of age, in the foot. Microscopically, it showed tumor cells in nests and lobules with abundant Homer-Wright rosettes. Immunohistochemically, tumor cells were immunoreactive for neural markers but also displayed an aberrant myoid phenotype. The prognostic implications of this anomalous phenotype are unclear as of now, but documentation of this is necessary for possible future references.

Morphological, immunohistochemical and electron microscopic compartive study of ewing's sarcoma, primitive neuroectodermal tumour and neuroblastoma

Ewings sarcoma [ES], primitive neuroectodermal tumour [PNET] and neurobl [NB] are most commonly considered in the differential diagnosis of small blue round cell tumor of infancy and childhood. The differential diagnosis between these overlapped tumours of utmost importance for therapy and prognosis. The aim of this study is to assess the morphological, the limnunohistochemical and the ultarstructural diagnostic features of these overlapping tumours. The material consisted of 18 cases including 8 cases of ES [7 bone aiid 1 soft tissue], 3 cases of PNET and 7 cases of neuroblastoma [all were primary tumors]. ES was diagnosed by its positivity for CD 99, the presence of glycogen either histochemically or by ElM along with the classic morphology of ovoid cells lacking rosettes and spindle cell pattern. For NB, it was diagnosed by its positivity for NSE and negativity for CD 99, the presence of neurits, neurosecretory granules and neuropils by E/M along with the rosettes by light microscopy and the absence of glycogen both histochemically and by E/M. For PNET, it had some features of ES as the presence of glycogen and positivity for CD 99 and some features of NB as positivity for NSE and the presence of neurosecretory granules and neurits as well as the occasional presence of rosettes by light microscopy. From the present study, it is recommended to make benefit from both the immunohistochemistry and E/M in the diagnosis of this overlapping group of tumors which was important for therapy and management

Small round blue cell tumor of seminal vesicle in a young patient

Seminal vesicle tumor is a rare disease with unclear origin. Generally, it is presented as a pelvic mass that can be detected by sonography and digital rectal exam. The authors report a 25-year-old patient with a pelvic mass which the magnetic resonance and surgical specimen reveal a seminal vesicle tumor. Immunohistochemical findings favored a primitive neuroectodermal tumor of the seminal vesicle. Herein, the treatment, histological and histochemical findings of this entity are discussed.

Tumor neuroectodérmico primitivo (PNET) de la mama: reporte de un caso / Primitive neuroectodermic tumor (PNET) of the breast: proposal of a case

El tumor neuroectodérmico primitivo, se incluye entre las neoplasias de células redondas y azules, forma parte de la familia de tumores de Ewing. El tumor neuroectodérmico primitivo es uno de los tumores que pertenecen a la familia de neoplasias formadas por células redondas, pequeñas, indiferenciadas que presentan una expresión fenotípica neuroectodérmica. Aparece con mayor frecuencia en la segunda década de la vida. Tiene varias formas de presentación, la más frecuente es en hueso, seguida de partes blandas, cavidad abdominal, área torácico-pulmonar, columna vertebral y sistema nervioso central. Excepcionalmente, se han descrito casos en miocardio, vulva y meninges. El caso que presentamos a continuación, es el segundo caso reportado en la literatura mundial diagnósticado en la glándula mamaria, así como, la revisión de la literatura en relación con esta patología

Malignant peripheral neuroepithelioma "peripheral neuroblastoma" a case report

Peripheral neuroepithelioma is a rate malignant tumour of primitive peripheral non autonomic nervous system. The tumour can occur at any age involving soft tissue mainly of lower extremities. Other sites of occurrence are the shoulder-thoracic region and the head and neck. It is a very aggressive tumour with early metastasis mainly to the lung. Herewith we report a case of 16 years old female who was presented with soft mass of labia majora of 3 years duration which has been rapidly enlarging in the last 6 months. The mass was excised and followed by administration of chemotherapy and radiotherapy. The patient developed secondaries in the lung 3 months after excision, with pleural effusion, but no local recurrence. However, eight months after the diagnosis and in January 2005, the patient died from the tumour

Meduloepitelioma teratóide maligno do globo ocular: relato de caso e revisão da literatura / Intraocular malignant teratoid medulloepithelioma: case report and review of the literature

Os autores relatam um caso de meduloepitelioma teratóide maligno intra-ocular acometendo uma menina de 7 anos com história de glaucoma congênito. O padrão histológico demonstrou ilhas de epitélio primitivo, com freqüentes estruturas tubulares e focos de cartilagem. Após procedimento cirúrgico, a paciente encontra-se bem, sem evidência de recorrência tumoral

Histopathological and Immunohistochemical Characteristics of Primary Renal Primitive neuroectodermal Tumor

We report a 32-year-old male who presented with huge [17x10.5x5 cm] right kidney with metastasis in the liver and retroperitoneal lymph nodes. Histological, detailed immunohistochemical studies and electron microscopic examinations were performed. Microscopy revealed small to intermediate sized cells with hyperchromatic nuclei, scanty cytoplasm, abundant mitosis with no pseudorossete formation. Immunohistochemical study revealed positive staining of the tumor cells for S100, neurofilaments, neuron specific enolase, vimentin and myoglobin. Primitive neuroectodermal tumors are rare malignant round cell tumors of the kidney. A correct diagnosis can be made on light microscopic features, and by immunohistochemically positive staining for more than one neural marker. This neoplasm should be differentiated from other renal neoplasms composed of small round cells

Cytodiagnosis of retroperitoneal primitive neuroectodermal tumour (PNET)--a case report.

A rare case of Retroperitoneal Primitive Neuro Ectodermal Tumour (PNET) in thirty years old female is presented. Fine needle aspiration cytology (FNAC) characterised by small round cells with scanty cytoplasm, poorly to well formed rosettes with neurofibrillary background; whereas periodic acid-schiff (PAS) rarely react with Primitive Neuro Ectodermal Tumour (PNET), prompted the diagnosis of PNET at cytology itself. Cytological appearances of PNET have been reviewed and the various differential diagnoses are discussed.

Tumor neuroectodérmico primitivo: neuroepitelioma periférico / Primitive neuroectodermal tumor of the chest wall

Presentamos un paciente de sexo masculino, de 29 años de edad, que consultó por tumoración dolorosa de pared toracoabdominal derecha. Los estudios por imágenes sugieren como diagnóstico diferencial: tumor de askin (neuroepitelioma), teniendo en cuenta sus características morfológicas y topográficas. Mediante el estudio anatomopatológico y con inmunohistoquímica se confirmó el diagnóstico de neuroepitelioma primitivo

Tumor neuroectodérmico primitivo periférico: uma revisão / Peripheral primitive neuroectodermal tunors: a revision

Os autores fizeram um levantamento bibliográfico sobre o conceito, classificaçäo, diagnóstico e prognóstico dos tumores neuroectodérmicos primitivos periféricos (PNETs), fazendo um comentário final quanto ao tratamento destas patologias

Tumor neuroepitelial disembrioplástico: estudo epidemiológico de uma única instituiçäo / Dysembryoplastic neuroepithelial tumor: an epidemiological study from a single institution

A real incidência do tumor neuroepitelial disembrioplástico (DNT) é desconhecida. Diferentes estimaçoes foram feitas, de acordo com o tipo de recrutamento dos pacientes. Nas séries provenientes de pacientes operados por epilepsia fármaco-resistente, as taxas variam amplamente, de 5 por cento a 87 por cento. Em uma série de 600 tumores pediátricos do sistema nervoso central, 9 DNT foram encontrados (1,5 por cento). Como o DNT foi identificado apenas em 1988, revimos nossos casos (1975-1991) de gangliogliomas (n=25), oligoastrocitomas (n=9), oligodendrogliomas do lobo temporal (n=11), astrocitomas grau II (OMS 1993) (n=44), independentemente da idade dos pacientes, bem como todos os astrocitomas grau II (n=61) e oligodendrogliomas (n=10) em pacientes até a idade de 20 anos. Sete DNT foram encontrados. Quatro haviam sido previamente diganosticados como gangliogliomas e 3, como astrocitomas grau II. A partir de 1992, 4 outros DNT foram diagnosticados, perfazendo um total de 11 casos. Oito pacientes tinham menos de 17 anos (6 a 17, média 10,3 anos) e três tinham 27, 42 e 51 anos. Oito tumores eram temporais, 1 frontal e 2 occipitais. Todos os pacientes apresentavam epilepsia fármaco-resistente. Dentre todos os tumores neuroepiteliais diagnosticados em nosso Serviço nos últimos 22 anos, DNT compreendem 1,2 por cento em pacientes até 20 anos (n=660), 0,24 por cento em pacientes acima de 20 anos (n=1254) e 0,63 por cento na totalidade dos pacientes (n=1914).

Dysembryoplastic neuroepithelial tumour of the central nervous system--a case report.

Dysembryoplastic neuroepithelial tumour (DNT) of the central nervous system is a recently recognized entity. We describe the clinical and characteristic histomorphological features in a patient with DNT. As this lesion carries a favourable prognosis, it becomes essential to make an accurate histopathological diagnosis.

Nonneoplastic, noninflammatory, cerebral intraventricular cysts

Atualmente, os cistos intraventriculares nao neoplasicos e nao inflamatorios sao divididos em dois grupos distintos: cistos neuroepiteliais (neurogliais) e cistos coloides. Os cistos neuroepiteliais e coloides eram considerados originarios do neuroepitelio primitivo, porem, estudos imuno-histoquimicos recentes sugerem uma origem endodermica para os cistos coloides...