Solitary fibrous tumor of the pleura with air cystic component.

We present an uncommon case of a solitary fibrous tumor of the pleura with the appearance of an air-containing cystic mass. We discuss the differential diagnosis through the imaging findings, the hypothetical origins of the air component, and the possible relationship between the air component and the aggressivity of the tumor.

Tumor fibroso pleural ¿son realmente benignos? ¿Cuándo deben operarse? / Pleural fibrous tumor, are they really benign? When should they have operation?

El tumor fibroso pleural es un tumor habitualmente asintomático, benigno y de lento crecimiento, que en un pequeño porcentaje de los casos tiene un comportamiento más agresivo. Para definir los criterios de malignidad es necesario un análisis inmunohistoquímico. El tratamiento de elección es la resección quirúrgica completa con márgenes de seguridad ya sea por toracotomía o por videotoracoscopia en función del tamaño. Se encuentra en estudio la utilización de terapia adyuvante radioterápica o quimioterápica que en el momento actual no cuenta con resultados significativos. Presentamos dos casos que fueron tratados de forma quirúrgica, con extirpación completa siendo el primero definido como maligno según los criterios histológicos y el segundo benigno, pero de alto riesgo. Solo uno de ellos recibió terapia adyuvante. (AU)

Solitary fibrous pleural tumor is a usually asymptomatic, benign and slow-growing tumor, which in a small percentage of cases has a more aggressive behavior. To define the malignancy criteria, an immunohistochemical analysis is necessary. The gold standard treatment is a complete surgical resection with safety margins either by thoracotomy or by videothoracoscopy depending on the size. The use of radiotherapy or chemotherapy as an adjuvant therapy is under study, which at the present time does not have significant results. We present two cases that were treated surgically, with complete removal, one being classified as malignant according to histological criteria and the other benign but high risk. Only one of them received adjuvant therapy. (AU)

Solitary fibrous tumor: Two cases report with a focus on the differential diagnosis / Tumor Fibroso Solitário: Relato de dois casos com foco no diagnóstico diferencial

Solitary fibrous tumor (SFT) is a neoplasm of fibroblastic/myofibroblastic origin with intermediate biological behavior. We report here two cases of SFT affecting an unusual anatomical site in 58-year-old and 40-year-old female patients and discuss the differential diagnosis of this lesion. In case 01, the lesion showed the clinical appearance of an asymptomatic "blister" with normal color, rubbery consistency, measuring 0.3 cm, and affected the lower lip; while in case 02, a symptomatic red nodular lesion with a soft consistency and measuring 0.5 cm affected the floor of the mouth. Excisional biopsies were performed. Microscopically, two well-delimited benign neoplasms were observed, exhibiting the proliferation of ovoid to spindle-shaped mesenchymal cells, vascular spaces with staghorn arrangement, and the absence of mitosis figures. Immunohistochemistry was performed in case 01 to assist in the diagnosis. Weak and diffuse immunostaining was observed for α-SMA and intense and diffuse immunopositivity for Bcl-2 and CD34. Based on histopathological and immunohistochemical features, a diagnosis of SFT was rendered in both cases. The low occurrence and nonspecific clinical features of oral SFT may make its clinical diagnosis difficult. Also, morphological and immunohistochemical are essential for differential diagnosis with other mesenchymal neoplasms.(AU)

O tumor fibroso solitário (TFS) é uma neoplasia de origem fibroblástica/miofibroblastica com comportamento biológico intermediário. Nesse artigo relatamos dois casos de TFS afetando sítios anatômicos incomuns em pacientes do sexo feminino de 58 anos e 40 anos e discutir os seus diagnósticos. No caso 01 clinicamente a lesão apresentou um aspecto de "bolha" assintomática, coloração normal da mucosa, consistência borrachoide medindo 0,3 cm, em região de lábio inferior, enquanto que no caso 02, como uma lesão sintomática, vermelha, nodular com consistência mole e medindo 0,5 cm afetando o assoalho bucal. As biópsias excecionais foram realizadas. Microscopicamente, observamos duas lesões neoplásicas bem delimitadas exibindo uma proliferação de células mesenquimais variando de ovoides a fusiformes, vasos sanguíneos em formato de "chifre de veado", com ausência de figuras de mitoses. No caso 01 foi realizado análise imuno-histoquímica para auxiliar no diagnóstico. Foi observado uma marcação fraca e difusa de α-SMA e uma intensa e difusa imunopositividade para o Bcl-2 e CD34.Baseado nos achados histopatológicos e imuno-histoquímicos o diagnóstico de TFS foi estabelecido em ambos os casos. A baixa ocorrência e os achados clínicos inespecíficos do TFS oral podem dificultar o diagnóstico clínico. Além disso, as análises morfológicas e imuno-histoquimicas são essenciais para realização do diagnóstico diferencial com outras neoplasias mesenquimais.(AU)_

Abordagem orbital para excisão de tumor fibroso solitário no seio frontal relativo a um caso clínico / Orbital approach for solitary fibrous tumor in the frontal sinus excision: case report / Abordaje orbitario para escisión de un tumor fibroso solitario en seno frontal: a propósito de un caso clínico

Apresentamos um caso de tumor fibroso solitário do seio frontal que herniava para a cavidade orbitária. Esta patologia é rara e cerca de trinta casos foram relatados na literatura mundial. O manejo foi feito com um grupo multidisciplinar e uma abordagem combinada transnasal e endoscópica externa através de uma incisão no nível do ângulo interno superior da órbita. A grande maioria da massa tumoral foi retirada e a fístula óssea foi selada com a colocação de uma malha orbital, que foi recoberta por uma membrana autóloga de fatores de crescimento, obtida e processada do sangue do próprio paciente. Os resultados imediatos foram muito bons e o acompanhamento é necessário para o controle do tumor... (AU)

We present a case of a solitary fibrous tumor of the frontal sinus that herniated within the orbital cavity. This pathology is rare and around thirty cases have been reported in the world literature. Management was done with a multidisciplinary group and a combined transnasal endoscopic and external approach through an incision in superior internal angle of the orbit. The tumor mass was removed, and the supraorbital bone was sealed with an orbit mesh, which was covered with an autologous membrane of growth factors, obtained, and processed from the patient's own blood. The immediate result was excellent, and follow-up is required to control the tumor... (AU)

Presentamos un caso de un tumor fibroso solitario de seno frontal que se hernió dentro de la cavidad orbitaria. Esta patología es rara y se han reportado una treintena de casos en la literatura mundial. El manejo se hizo con un grupo multidisciplinario y un abordaje combinado endoscópico transnasal y externo a través de una incisión a nivel de ángulo superior interno de la órbita. Se retiró la masa tumoral en su gran mayoría, y se selló la fístula ósea con la colocación de una malla para órbita, la cual se cubrió con una membrana autóloga de factores de crecimiento, obtenida y procesada de la propia sangre del paciente. Los resultados inmediatos fueron muy buenos y se precisa seguimiento para control de la tumoración... (AU)

Tumor fibroso solitario (TFS) parafaríngeo: reporte de caso y revisión de literatura / Parapharyngeal solitary fibrous tumor (SFT): case report and literature review

El espacio parafaríngeo es una región donde puede surgir un amplio espectro de tumores, que son poco frecuentes y comprenden solo el 0,5 al 1,5% de las neoplasias de cabeza y cuello. Generalmente, son hallazgos y suelen presentarse como masas asintomáticas. Incluye neoplasias primarias, extensión directa de regiones adyacentes y enfermedad metastásica. La literatura describe múltiples patologías e histologías que pueden surgir de esta zona, entre ellas, tenemos los tumores fibrosos solitarios, que son un espectro de neoplasias mesenquimatosas fibroblásticas de histogénesis incierta, que generalmente involucran la pleura. Son lesiones muy poco frecuentes y su localización parafaríngea es excepcional, siendo su primer reporte en la literatura en 1993. Se presenta el caso de un tumor fibroso solitario del espacio parafaríngeo evaluado en nuestro centro, con su enfrentamiento diagnóstico, resolución quirúrgica y seguimiento respectivo, con el objetivo de presentar esta patología poco frecuente a nuestros colegas y contribuir al conocimiento médico.

The parapharyngeal space is a region where a wide spectrum of tumors can arise, which are rare and comprise only 0.5% to 1.5% of head and neck neoplasms. They are generally findings and usually present as asymptomatic masses. Includes primary neoplasms, direct extension from adjacent regions, and metastatic disease. The literature describes multiple pathologies and histologies that can arise from this area, among them, we have solitary fibrous tumors, which are a spectrum of fibroblastic mesenchymal neoplasms of uncertain histogenesis, which are generally the pleura. It is a very rare lesion and its parapharyngeal location is exceptional, being its first report in the literature in 1993. We present the case of a solitary fibrous tumor of the parapharyngeal space evaluated in our center, with its diagnos- tic confrontation, surgical resolution and respective follow-up, with the aim of presenting this rare pathology to our colleagues and contributing to medical knowledge.

Tumor fibroso solitario de próstata: informe de caso y revisión de la literatura / Solitary fibrous tumor of the prostate: case report and literature review

El tumor fibroso solitario (TFS) es una neoplasia mesenquimatosa de tipo fibroblástico que, a pesar de ser localizado principalmente en pleura, se ha observado en otros órganos como la próstata. Por su parte, el tumor fibroso solitario de la próstata es una neoplasia de baja incidencia, crecimiento lento y potencial maligno incierto, que generalmente se compone de células fusiformes de apariencia citológicamente benignas, dispuestas en una arquitectura desorganizada, mezcladas con colágeno y pequeños vasos sanguíneos. Establecer su diagnóstico se ha vuelto más reproducible desde la identificación de la fusión de los genes NAB2-STAT6 por biología molecular, que lleva a la sobreexpresión de STAT6 por inmunohistoquímica, el cual es un marcador muy sensible y específico para TFS. Presentamos el caso clínico de un paciente que debutó con síntomas de compresión vesical, en quien se identificó una masa con epicentro en la próstata que infiltraba la vejiga y llegaba a la pared rectal, y que luego de estudios de patología, inmunohistoquímica y pruebas moleculares se clasificó como un TFS de la próstata, finalmente tratado con cistoprostatectomía radical más derivación urinaria

Solitary fibrous tumor (SFT) is a mesenchymal neoplasm of fibroblastic type, which despite being located mainly in the pleura, has been observed in other organs such as the prostate. On the other hand, solitary fibrous tumor of the prostate is a rare neoplasm, slow growing, and of uncertain malignant potential, which is generally composed of spindle cells of cytologically benign appearance, arranged in a disorganized architecture, mixed with collagen and small blood vessels. Establishing its diagnosis has become more reproducible since the identification of the NAB2-STAT6 gene fusion by molecular biology, leading to the overexpression of STAT6 by immunohistochemistry, a very sensitive and specific marker for SFT. We present a clinical report of a patient who consulted with symptoms of bladder compression, in whom a mass was identified with the epicenter in the prostate infiltrating into the bladder and reaching the rectal wall. Following histopathology study, immunohistochemistry and molecular tests it was classified as a SFT of the prostate, finally treated with radical cystoprostatectomy plus urinary shunt

Recurrent meningeal malignant tumor: Assessment of differences in the solitary fibrous tumor/hemangiopericytoma spectrum through a case report / Tumor maligno recurrente de origen meníngeo: evaluación de las diferencias de la entidad tumor fibroso solitario/hemangiopericitoma mediante un caso clínico

Solitary fibrous tumors (SFTs) are neoplasms that grow from mesenchymal fusiform cells. In the central nervous system, meninges are the common origin of these neoplasms. Although literature reports mostly SFT as benign neoplasm, malignancy data have been described in recurrences or metastatic lesions. Definitive diagnosis includes immunohistochemical profiles assessing cellular positivity for CD34, vimentin, CD99 and Bcl-2. Recent studies have demonstrated NAB2-STAT6 gene fusion as a distinct molecular feature of SFT with overexpression of the fusion protein NAB2-STAT6 in nuclei of these cells. Since several years, pathologists have grouped SFT and hemangiopericytomas (HPC) as different phenotypes of the same entity although both neoplasms do not share numerous features. This article, based on a case of a recurrent malignant SFT, aims to emphasize differences in the SFT/HPC spectrum due to the diagnostic, therapeutic and prognostic implications (AU)

Los tumores fibrosos solitarios (TFS) son neoplasias que crecen a partir de células mesenquimales y las meninges constituyen su origen preferente en el sistema nervioso central. Aunque la literatura relaciona la mayoría de los TFS como neoplasias benignas, se describen datos de malignidad en recidivas tumorales o lesiones metastásicas. El diagnóstico definitivo incluye el perfil inmunohistoquímico, que evalúa la positividad celular para CD34, vimentina, CD99 y Bcl-2. Estudios recientes han demostrado la fusión del gen NAB2-STAT6 como una característica molecular distintiva de los TFS, con sobreexpresión de la proteína de fusión NAB2-STAT6 en los núcleos de las células. Los patólogos han agrupado los TFS y los hemangiopericitomas como diferentes fenotipos de una misma entidad, aunque ambas neoplasias no comparten numerosas características. Este artículo, basado en un caso de una lesión maligna recurrente, tiene como objetivo enfatizar las diferencias en el espectro SFT/hemangiopericitoma por sus implicaciones diagnósticas, terapéuticas y pronósticas (AU)

Recurrent meningeal malignant tumor: Assessment of differences in the solitary fibrous tumor/hemangiopericytoma spectrum through a case report.

Solitary fibrous tumors (SFTs) are neoplasms that grow from mesenchymal fusiform cells. In the central nervous system, meninges are the common origin of these neoplasms. Although literature reports mostly SFT as benign neoplasm, malignancy data have been described in recurrences or metastatic lesions. Definitive diagnosis includes immunohistochemical profiles assessing cellular positivity for CD34, vimentin, CD99 and Bcl-2. Recent studies have demonstrated NAB2-STAT6 gene fusion as a distinct molecular feature of SFT with overexpression of the fusion protein NAB2-STAT6 in nuclei of these cells. Since several years, pathologists have grouped SFT and hemangiopericytomas (HPC) as different phenotypes of the same entity although both neoplasms do not share numerous features. This article, based on a case of a recurrent malignant SFT, aims to emphasize differences in the SFT/HPC spectrum due to the diagnostic, therapeutic and prognostic implications.

Tumor fibroso solitario intrapulmonar de patrón adenofibromatoso: un reporte de caso / Solitary intrapulmonary fibrous tumor with an adenofibromatous pattern: A case report

El tumor fibroso solitario es una neoplasia de origen mesenquimal que suele darse en la pleura y que normalmente tiene un curso benigno. La localización intrapulmonar es rara y aún más raro es el patrón adenofibromatoso. Presentamos un caso de un tumor fibroso solitario intrapulmonar con características adenofibromatosas en un paciente con antecedente de adenocarcinoma de próstata. El tumor mostró características inmunohistoquímicas de positividad para STAT6, CD34 y Bcl-2.(AU)

Solitary fibrous tumor is a neoplasm of mesenchymal origin that generally occurs in the pleura and is usually benign. An intrapulmonary location is rare and the adenofibromatous pattern is even more infrequent. We present a case of a solitary intrapulmonary fibrous tumor with adenofibromatous characteristics in a patient with a history of adenocarcinoma of the prostate. Immunohistochemically, the tumor was positive for STAT6, CD34 and Bcl-2.(AU)

[Solitary intrapulmonary fibrous tumor with an adenofibromatous pattern: A case report]. / Tumor fibroso solitario intrapulmonar de patrón adenofibromatoso: un reporte de caso.

Solitary fibrous tumor is a neoplasm of mesenchymal origin that generally occurs in the pleura and is usually benign. An intrapulmonary location is rare and the adenofibromatous pattern is even more infrequent. We present a case of a solitary intrapulmonary fibrous tumor with adenofibromatous characteristics in a patient with a history of adenocarcinoma of the prostate. Immunohistochemically, the tumor was positive for STAT6, CD34 and Bcl-2.

[Fat-forming solitary fibrous tumor with NAB2/ STAT6 gene fusion. Case report of genial location and literature review]. / Tumor fibroso solitario variedad lipomatosa con fusión génica NAB2/STAT6. Estudio de un caso de localización geniana y revisión de la literatura.

The lipomatous variety solitary fibrous tumor is a soft tissue neoplasm composed of mature adipose tissue and hemangiopericytoma areas. A 53-year-old man consulted for facial asymmetry and maxillofacial magnetic resonance imaging showed a cystic lesion, 3 x 2 cm in size, in front of the anterior wall of the maxillary sinus. Histologically, there were dense spindle cells expressing CD34, CD99, Bcl-2, and STAT6, myxoid zones, hemangiopericytomatous blood vessels, and S100 positive adipocytes. NAB2/STAT6 gene fusion was revealed by RT-PCR. The main differential diagnosis was raised with the spindle cell lipoma and malignant variant of the lipomatous solitary fibrous tumor. STAT6 overexpression and NAB2/STAT6 gene fusion are specific for lipomatous solitary fibrous tumor and the presence of lipoblasts and atypical lipomatous tumor areas suggests malignancy. These tumors located in the head and neck region have a benign biological behavior.

Tumor fibroso solitario variedad lipomatosa con fusión génica NAB2/STAT6. Estudio de un caso de localización geniana y revisión de la literatura / Fat-forming solitary fibrous tumor with NAB2/ STAT6 gene fusion. Case report of genial location and literature review

El tumor fibroso solitario variedad lipomatosa es una neoplasia de partes blandas compuesta por tejido adiposo maduro y áreas de hemangiopericitoma. Un varón de 53 años se presentó clínicamente con asimetría facial. La resonancia magnética maxilofacial demostró una lesión quística, de 3 x 2 cm, por delante de la pared anterior del seno maxilar. Histológicamente, había áreas fusocelulares densas que expresaban CD34, CD99, Bcl-2 y STAT6, zonas mixoides, vasos sanguíneos hemangiopericitomatosos y adipocitos S100 positivos. La fusión génica NAB2/STAT6 fue revelada mediante RT-PCR. El principal diagnóstico diferencial se planteó con el lipoma de células fusiformes y la variante maligna del tumor fibroso solitario lipomatoso. La sobreexpresión de STAT6 y la fusión génica NAB2-STAT6 son específicas del tumor fibroso solitario lipomatoso y la presencia de lipoblastos y áreas de tumor lipomatoso atípico sugiere malignidad. Estos tumores en cabeza y cuello tienen un comportamiento biológico benigno.(AU)

The lipomatous variety solitary fibrous tumor is a soft tissue neoplasm composed of mature adipose tissue and hemangiopericytoma areas. A 53-year-old man consulted for facial asymmetry and maxillofacial magnetic resonance imaging showed a cystic lesion, 3 x 2 cm in size, in front of the anterior wall of the maxillary sinus. Histologically, there were dense spindle cells expressing CD34, CD99, Bcl-2, and STAT6, myxoid zones, hemangiopericytomatous blood vessels, and S100 positive adipocytes. NAB2/STAT6 gene fusion was revealed by RT-PCR. The main differential diagnosis was raised with the spindle cell lipoma and malignant variant of the lipomatous solitary fibrous tumor. STAT6 overexpression and NAB2/STAT6 gene fusion are specific for lipomatous solitary fibrous tumor and the presence of lipoblasts and atypical lipomatous tumor areas suggests malignancy. These tumors located in the head and neck region have a benign biological behavior.(AU)

Tumor fibroso solitario gigante de pleura / Giant solitary fibrous tumor of the Pleura

Resumen Objetivo: Reportar el caso de una masa gigante en hemitórax izquierdo de 19 cm de diámetro en un paciente de 59 años que debutó con disnea, tos y dolor torácico, confirmándose por estudio imagenológico. Materiales y Método: Registro clínico de un paciente al cual se le diagnostica tumor fibroso solitario de pleura, siendo intervenido quirúrgicamente para exéresis de la lesión. Resultados: Se realiza toracotomía posterolateral izquierda para exéresis de tumor gigante, requiriendo además, resección de diafragma y pericardiectomía parcial con evolución favorable. Discusión: El tumor fibroso solitario es una neoplasia rara derivada del mesénquima que afecta más comúnmente a la pleura, típicamente bien circunscrita, pediculada, con vasos dentro del pedículo tumoral, pudiendo llegar a ser de gran tamaño, siendo considerados gigantes cuando tienen más de 15 cm de diámetro. Conclusión: El diagnóstico correcto es de vital importancia, ya que con la resección quirúrgica es potencialmente curable. El tratamiento quirúrgico puede efectuarse por toracotomía o videotoracoscopia, dependiendo del tamaño del tumor. A pesar del comportamiento benigno, requiere seguimiento a largo plazo debido a la tendencia a la recidiva.

Aim: To report the case of a 19 cm diameter giant mass in the left hemithorax in a 59-year-old patient who presented with dyspnea, cough and chest pain, confirmed by imaging study. Materials and Method: Clinical record of a patient who was diagnosed with a solitary fibrous tumor of the pleura, undergoing surgery to excise the lesion. Results: A left posterolateral thoracotomy was performed to excise the giant tumor, also requiring resection of the diaphragm and partial pericardiectomy with favorable evolution. Discussion: The solitary fibrous tumor is a rare neoplasm derived from the mesenchyme that most commonly affects the pleura, typically well circumscribed, pedunculated, with vessels within the tumor pedicle, and can become large, being considered giant when they are larger than 15 cm diameter. Conclusión: The correct diagnosis is of vital importance, since surgical resection it a potentially curable treatment. Surgical treatment can be performed by thoracotomy or videothoracoscopy, depending on the size of the tumor. Despite the benign behavior, it requires long-term follow-up due to the tendency to recur.

Síndrome paraneoplásico de Doege-Potter: manejo paliativo / Doege-Potter syndrome: palliative care

El síndrome de Doege-Potter es un síndrome paraneoplásico excepcional asociado a los tumores fibrosos solitarios, otra entidad muy poco común. Se caracteriza por hipoglucemias sintomáticas mantenidas por la sobreproducción de factor de crecimiento insulínico tipo 2, una molécula muy similar a la insulina. La intervención quirúrgica es la única opción para evitar la aparición de este síndrome. En formas inoperables, la quimioterapia ha demostrado eficacia en el control de la hipoglucemia. No obstante, el uso de corticoides es la opción terapéutica indicada en el control de síntomas derivados de esta entidad cuando el paciente no es candidato a ningún otro tratamiento agresivo, mejorando su calidad de vida. (AU)

Doege-Potter syndrome is a rare paraneoplastic syndrome associated with solitary fibrous tumors, which also represent another uncommon disease. It is characterized by symptomatic hypoglyce- mia due to overproduction of insulin growth factor type 2, a molecule similar to insulin. Surgical treatment is the only option to prevent this syndrome from developing. In inoperable cases, chemotherapy has shown efficacy in the management of hypoglycemia. Nevertheless, the use of corticosteroids has been recognized as the best therapeutic option to keep symptoms under control when the patient is not a candidate to any other agressive treatment, improving quality of life. (AU)

Solitary fibrous tumor of the left adrenal gland associated with Doege-Potter syndrome. Case report.

We present the case of a 71-year-old man with a history of type 2 diabetes mellitus manifesting abdominal pain, weight loss, dyspnea on small efforts, muscle weakness, and left subcostal swelling. Associated with this, he developed frequent episodes of syncope, diaphoresis, and night sweats, during which blood glucose levels below 50 mg/dL and improvement were documented after the administration of hypercaloric beverages or intravenous dextrose. Abdominal computed tomography revealed the presence of a tumor of approximately 20 cm dependent on the left adrenal gland. Histopathological diagnosis of a solitary retroperitoneal fibrous tumor was obtained, confirmed by immunohistochemistry.

Se presenta el caso de un varón de 71 años con antecedente de diabetes mellitus tipo 2 que manifiesta dolor abdominal, pérdida de peso, disnea de pequeños esfuerzos, debilidad muscular y aumento de volumen subcostal izquierdo. Asociado a esto desarrolló episodios frecuentes de síncope, diaforesis y sudoraciones nocturnas, durante los cuales se documentaron cifras de glucemia < 50 mg/dl y mejoría tras la administración de bebidas hipercalóricas o dextrosa intravenosa. La tomografía computarizada abdominal reveló la presencia de una tumoración de aproximadamente 20 cm dependiente de la glándula suprarrenal izquierda. Se obtuvo diagnóstico histopatológico de tumor fibroso solitario retroperitoneal confirmado por inmunohistoquímica.

Tumor fibroso solitario gigante de pleura. Serie de casos / Giant Solitary Fibrous Tumor of the Pleura. Case Series

Resumen Introducción. El tumor fibroso solitario de pleura (TFSP) es una neoplasia poco frecuente, con aproximadamente 1.000 casos reportados en la literatura mundial. La aproximación diagnóstica inicial se realiza con estudios imagenológicos. Métodos. De forma retrospectiva, se recopilaron cuatro casos de pacientes con TFSP gigante operados en nuestra institución. Se describen las características sociodemográficas, clínicas, imagenológicas, macroscópicas y microscópicas de cada caso. Resultados. Todos los pacientes de la serie cursaron con manifestaciones clínicas, con un promedio de 23,75 meses de evolución. El 50% de los tumores se localizaron en la cavidad pleural derecha y el 50% en la izquierda. En tomografía computarizada (TC) de tórax, los cuatro casos se presentaron como una masa sólida, de densidad heterogénea, con diámetros mayores entre 17 y 22 cm y contornos variables (lisos en tres casos y lobulados en un paciente). Se observaron calcificaciones intratumorales en dos casos y derrame pleural en tres pacientes. En cirugía, todas las masas presentaron pedículos. El análisis histológico e inmuno-químico confirmó la naturaleza benigna de tres casos y malignidad en una de las neoplasias. Conclusiones. Los TFSP generalmente son benignos y de buen pronóstico. Sin embargo, entre 10 y 20% de esos tumores son malignos. Las imágenes diagnósticas pueden sugerir el diagnóstico de TFSP, pero la confirmación de la naturaleza de la lesión debe realizarse con el análisis histopatológico de toda la pieza quirúrgica.

Abstract Introduction. Solitary fibrous tumor of the pleura (SFTP) is a rare neoplasm, with ~1.000 cases reported in the worldwide literature. The initial diagnostic approach is performed by imaging studies. Methods. Retrospectively, we collected four cases of patients with giant SFTP operated in our institution. The sociodemographic, clinical, imaging, macroscopic, and microscopic characteristics of each case are described. Results. All the patients in the series had clinical manifestations, with an average of 23.75 months of evolution. 50% of the tumors were located in the right pleural cavity and 50% in the left. In chest computed tomography (CT), the four cases presented as a solid mass, of heterogeneous density, with greater diameters between 17 and 22 cm, and variable contours (smooth in three cases and lobulated in one patient). Intratumoral calcifications were observed in two cases and pleural effusion in three patients. In surgery, all masses presented pedicles. The histological and immunochemical analysis confirmed the benign nature of three cases and malignancy in one of them. Conclusions. SFTPs are usually benign and have a good prognosis. However, between 10 and 20% of these tumors are malignant. Diagnostic images may suggest the diagnosis of SFTP, but confirmation of the nature of the lesion should be made with the histopathological analysis of the entire surgical specimen.

Tumor fibroso solitario de la pleura / Solitary fibrous tumor of the pleura

El tumor fibroso solitario de la pleura (TFSP) representa una neoplasia benigna de evolución habitualmente silente, hallazgo incidental y heterogeneidad en su presentación. Raramente se malignizan y la sintomatología se relaciona fundamentalmente con el compromiso por compresión de las estructuras vecinas. Su tratamiento es la cirugía. Se describe el caso de un paciente masculino de 49 años con antecedentes de hipertensión arterial, diabetes mellitus y obesidad que consultó al Servicio de urgencias por disnea. Se solicitó tomografía de tórax que evidenció voluminosa masa de densidad de partes blandas en hemitórax izquierdo con desplazamiento del mediastino y descenso del diafragma del mismo lado. La fibrobroncoscopia no evidenció lesión endoluminal. Fue evaluado por Cirugía del Tórax. Se realizó abordaje de la masa mediante toracotomía postero lateral izquierda. El estudio anatomopatológico informó formación tumoral de 25 × 16 × 13 cm, peso de 1905 gr y en la microscopía se describió proliferación celular fibroblástica, células fusiformes de núcleos pequeños ovoides y escaso citoplasma dispuestas en haces desordenados con colágeno interpuesto. La inmunohistoquímica informó vimentina y CD34 positivos. Se realizó el diagnóstico de tumor fibroso solitario de la pleura. La evolución posterior fue buena.

The solitary fibrous tumor of the pleura (SFTP) represents a benign neoplasm of commonly silent evolution, incidental finding and heterogeneous presentation. It rarely becomes malignant and symptoms mainly result from the involvement of neighboring structures due to compression. It is treated with surgery. We describe the case of a 49-year-old male patient with history of arterial hypertension, diabetes mellitus and obesity who consulted the Emergency Services because he was experiencing dyspnea. We requested chest tomography that showed a voluminous soft tissue density mass in the left hemithorax with mediastinal shift and decreased diaphragm on the same side. The fibrobronchoscopy didn't show endoluminal lesion. The patient was evaluated by the Thorax Surgery staff. The mass was treated by means of left posterolateral thorachotomy. The anatomopathological study reported the formation of a tumor of 25 × 16 ×13 cm and 1905 gr, and the microscopy described fibroblast cell proliferation, spindle cells of small ovoid nuclei and very little cytoplasm placed in disorganized bundles with collagen interposition. The immunohistochemistry disclosed positive vimentin and CD34. The patient was diagnosed with solitary fibrous tumor of the pleura, with good subsequent evolution.

Resultados en el tratamiento de los hemangiopericitomas intracraneanos. Serie de casos / Results in the treatment of intracranial hemangiopericytomas. Case series

Objetivo Los hemangiopericitomas intracraneanos (HPC) son tumores de muy baja frecuencia, alta recidiva local y riesgo de metástasis extracraneal. El objetivo del siguiente trabajo es presentar los resultados en el tratamiento de los HPC en nuestra institución en los últimos 20 años y realizar una revisión de la literatura del tema. Material y métodos Se realizó un estudio retrospectivo que incluyó a los pacientes con diagnóstico de tumor fibroso solitario/hemangiopericitoma (TFS/HPC) intracraneanos intervenidos quirúrgicamente en el periodo 1997-2017. Se incluyeron pacientes con inmunomarcación positiva para STAT-6 y grado histológico II-III. Se recabaron datos demográficos, características tumorales, tratamiento y sobrevida de estos pacientes. Resultados Un total de 19 pacientes cumplieron los criterios de inclusión. La mediana de seguimiento fue de 96 meses (12-230). La mortalidad fue del 21% (n = 4). El 57,9% presentaron al menos una recidiva tumoral (n = 11) (con una recurrencia del 6, del 67 y del 90% a 1, 5 y 10 años, respectivamente). Cinco pacientes presentaron metástasis extracraneal. Tuvieron mayor sobrevida los pacientes con tumores < 6 cm (p < 0,05). Conclusiones Se presentó una serie de pacientes operados de TFS/HPC según los nuevos criterios de la OMS. El tamaño es un factor predictor de sobrevida. Actualmente no existen criterios validados de resección quirúrgica en esta patología. Una clasificación con orientación quirúrgica sería de utilidad en el futuro (AU)

Objective Intracranial hemangiopericytoma (HPC) is a rare central nervous system tumor characterized by its low incidence, high rate of local recurrence and risk of metastasis. The main objectives of this paper are two: to show the results in the treatment of HPC in our institution in the last 20 years and to make a review of the literature on this topic. Methods Retrospective review that includes patients diagnosed with intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) that have undergone surgery from 1997 to 2017. It includes patients that had nuclear expression of STAT-6 (detected by immunohistochemistry) and grade II/III histopathological diagnosis (defined by the World Health Organization in 2016). We collected demographic data, tumor characteristics, treatment and survival of these patients. Results A total of 19 patients fulfilled inclusion criteria. The median follow up was 96 months (12-230). The mortality rate was 21% (n = 4). 57.9% of patients presented at least one tumor recurrence (n = 11) (recurrences of 6%, 67% y 90% at 1, 5 and 10 years). Five patients presented extracranial metastasis. Patients with tumors < 6 cm had greater survival (P < .05). Conclusions A series of patients undergoing SFT/HPC were presented according to the new WHO criteria. Size is a predictor of survival. Currently there are no validated criteria for surgical resection in this pathology. A classification with surgical guidance would be useful (AU)

Results in the treatment of intracranial hemangiopericytomas. Case series. / Resultados en el tratamiento de los hemangiopericitomas intracraneanos. Serie de casos.

OBJECTIVE: Intracranial hemangiopericytoma (HPC) is a rare central nervous system tumor characterized by its low incidence, high rate of local recurrence and risk of metastasis. The main objectives of this paper are two: to show the results in the treatment of HPC in our institution in the last 20years and to make a review of the literature on this topic. METHODS: Retrospective review that includes patients diagnosed with intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) that have undergone surgery from 1997 to 2017. It includes patients that had nuclear expression of STAT-6 (detected by immunohistochemistry) and gradeII/III histopathological diagnosis (defined by the World Health Organization in 2016). We collected demographic data, tumor characteristics, treatment and survival of these patients. RESULTS: A total of 19 patients fulfilled inclusion criteria. The median follow up was 96 months (12-230). The mortality rate was 21% (n=4). 57.9% of patients presented at least one tumor recurrence (n=11) (recurrences of 6%, 67% y 90% at 1, 5 and 10years). Five patients presented extracranial metastasis. Patients with tumors <6cm had greater survival (P<.05). CONCLUSIONS: A series of patients undergoing SFT/HPC were presented according to the new WHO criteria. Size is a predictor of survival. Currently there are no validated criteria for surgical resection in this pathology. A classification with surgical guidance would be useful.

El análisis inmunohistoquímico para el diagnóstico del tumor fibroso solitario/hemangiopericitoma / Immunohistochemical analysis for the diagnosis of solitary fibrous tumor/hemangiopericytoma

Resumen El tumor fibroso solitario/ hemangiopericitoma (TFS/HP) es un tumor extraaxial de origen mesenquimático de infrecuente observación, que usualmente se confunde con el meningioma, del cual puede ser clínica y radiológicamente indistinguible. El análisis molecular con la detección de la expresión nuclear STAT6 (signal transducer and activator of transcription 6) o la fusión NAB2-STAT6 (NGFI-A binding protein 2) es recomendable para confirmar el diagnóstico. Presentamos 3 casos clínicos, 2 mujeres y 1 varón, con diagnóstico anatomopatológico de meningioma meningotelial en el primer caso; y los casos 2 y 3 con sospecha radiológica de meningioma. La revisión anatomopatológica con estudio molecular permitió certificar el diagnóstico de TFS/ HP. Para el diagnóstico diferencial entre TFS/HP meníngeo y meningioma, se recomienda buscar la expresión de STAT6 como primer paso o la fusión NAB2-STAT6. La revisión de las muestras de biopsia debe estar garantizada en todos los pacientes, inclusive en aquellas que fueron estudiadas en Servicios de Patología Nivel 3.

Abstract The solitary fibrous tumor/ hemangiopericytoma (TFS/HP) is a rare mesenchymal extraaxial tumour. TFS/HP can sometimes be difficult to distinguish from other extra-axial tumors like meningioma, which can be clinically and radiologically indistinguishable. Molecular analysis with STAT6 (signal transducer and activator of transcription 6) nuclear expression or NAB2-STAT6 (NGFI-A binding protein 2) fusion is recommended to confirm the diagnosis. We present 3 cases, 2 women and 1 male, with pathological diagnosis of meningothelial meningioma in the first case; cases 2 and 3 with radiological suspicion of meningioma. The pathological review with molecular study certified the diagnosis of TFS/HP. For differential diagnosis between meningeal TFS/HP and meningioma, it is recommended to look for STAT6 expression as a first step, or NAB2-STAT6 fusion in order to confirm TFS/HP. The review of biopsy samples must be guaranteed in all patients, including those who were studied in Pathology Services Level 3.