Pheochromocytoma/paraganglioma type 5 syndrome as a cause of secondary hypertension in a Colombian patient: case report / Síndrome de feocromocitoma-paraganglioma de tipo 5 como causa de hipertensión arterial en una paciente colombiana: reporte de caso

Pheochromocytoma is a tumor derived from neural crest cells able to produce sympathomimetic substances and, hence, a particular clinical picture. It is responsible for less than 1% of high blood pressure cases, with an estimated incidence between 0.4 and 0.6 cases per 100,000 people each year, and an average survival of seven years. Pheochromocytoma is a solid tumor with a high genetic component, as heritability can reach 40%. Once diagnosed, its treatment and prognosis are partly conditioned by the associated pathogenic variants that can be documented, especially those related to RET, SDHx, VHL, and NF1 genes. We present the case of a young woman with abdominal pain and high blood pressure, who was found to have a pheochromocytoma. Genetic testing detected a rare and recently discovered pathogenic variant: the SDHA:c.1A>C (p.Met1Leu). The patient responded adequately to the surgical treatment and continued the follow-up without documented recurrences. The diagnostic approach for pheochromocytoma patients must start with a clinical suspicion, followed by metabolite measurement in blood and urine, and finally, imaging. Currently, technology development allows precision medicine applicability. In this case of pheochromocytoma, recent developments in precision medicine resulted in the detection of associated genetic components involving the patient and her family. Adequate screening of the index patient is required for documenting pathogenic variants and better characterizing the disease.

El feocromocitoma es un tumor derivado de las células de la cresta neural con la capacidad de producir sustancias simpaticomiméticas y, por ende, un cuadro clínico particular. Causa menos del 1 % de los casos de hipertensión arterial sistémica y su incidencia se estima entre 0,4 y 0,6 casos por 100.000 personas cada año, con una supervivencia media de siete años. De todos los tumores sólidos, el feocromocitoma tiene un mayor componente genético, que puede heredarse hasta en el 40 % de los casos. Una vez diagnosticada la enfermedad, se debe definir el tratamiento y el pronóstico, en parte condicionados por las variantes genéticas asociadas, en especial RET, SDHx, VHL y NF1. Se presenta el caso de una mujer joven con dolor abdominal e hipertensión arterial sistémica, a quien se le diagnosticó feocromocitoma. Al secuenciar el exoma, se identificó una variante patogénica extremadamente rara y de reciente descubrimiento: SDHA: c.1A>C (p.Met1Leu). La paciente respondió adecuadamente al tratamiento quirúrgico y continuó en seguimiento sin recurrencias. El abordaje diagnóstico de los pacientes con feocromocitoma comienza con la sospecha clínica, seguida de la medición de determinados metabolitos en sangre y orina, y, finalmente, los estudios de imagenología. Los desarrollos tecnológicos actuales permiten la aplicación de la medicina de precisión en este campo. En este caso de feocromocitoma, se identificó un componente genético importante que no solo afecta al paciente, sino también, a sus familiares. La tamización adecuada del caso índice permite identificar mutaciones y caracterizar mejor la enfermedad.

Jugular Foramen Paragangliomas.

Paragangliomas are the most common tumors at jugular foramen and pose a great surgical challenge. Careful clinical history and physical examination must be performed to adequately evaluate neurological deficits and its chronologic evolution, also to delineate an overview of the patient performance status. Complete imaging evaluation including MRI and CT scans should be performed, and angiography is a must to depict tumor blood supply and sigmoid sinus/internal jugular vein patency. Screening for multifocal paragangliomas is advisable, with a whole-body imaging. Laboratory investigation of endocrine function of the tumor is necessary, and adrenergic tumors may be associated with synchronous lesions. Preoperative prepare with alpha-blockage is advisable in norepinephrine/epinephrine-secreting tumors; however, it is not advisable in exclusively dopamine-secreting neoplasms. Best surgical candidates are young otherwise healthy patients with smaller lesions; however, treatment should be individualized each case. Variations of infratemporal fossa approach are employed depending on extensions of the mass. Regarding facial nerve management, we avoid to expose or reroute it if there is preoperative function preservation and prefer to work around facial canal in way of a fallopian bridge technique. If there is preoperative facial nerve compromise, the mastoid segment of the nerve is exposed, and it may be grafted if invaded or just decompressed. A key point is to preserve the anteromedial wall of internal jugular vein if there is preoperative preservation of lower cranial nerves. Careful multilayer closure is essential to avoid at most cerebrospinal fluid leakage. Residual tumors may be reoperated if growing and presenting mass effect or be candidate for adjuvant stereotactic radiosurgery.

Feocromocitoma y paraganglioma en un hospital pediátrico de Argentina. Serie de casos / Pheochromocytoma and paraganglioma at a children's hospital in Argentina. A case series

El feocromocitoma y el paraganglioma son tumores neuroendocrinos secretores de catecolaminas. Los feocromocitomas se originan en la médula suprarrenal, mientras que los paragangliomas son extraadrenales. Se describe una serie de casos de niños con diagnóstico anatomopatológico de feocromocitoma o paraganglioma que consultaron en un hospital pediátrico de alta complejidad de Argentina. Se incluyeron 21 pacientes, 14 varones, con una mediana de edad de 11,4 años; 8 casos con feocromocitoma y 13 casos con paraganglioma. Se presentaron con hipertensión arterial 14/21. La mayoría de los paragangliomas tuvieron localización paraaórtica (9/13). Debido a que representan una causa potencialmente curable de hipertensión arterial, la sospecha clínica es muy importante. El diagnóstico temprano y la instauración de un tratamiento antihipertensivo adecuado, que permita afrontar la cirugía con normotensión arterial, aseguran la curación en la mayoría de los casos si la resección tumoral es completa.

Pheochromocytomas and paragangliomas are neuroendocrine tumors producing catecholamines. Pheochromocytomas occur in the adrenal medulla, while paragangliomas are those that occur outside the adrenal gland. Here we describe a case series of children with a pathological diagnosis of pheochromocytoma or paraganglioma who consulted at a tertiary care children's hospital in Argentina. A total of 21 patients (14 males) were included; their median age was 11.4 years; 8 children had pheochromocytoma and 13, paraganglioma. Arterial hypertension was observed in 14/21. Most paragangliomas were para-aortic (9/13). Since they are a potentially curable cause of hypertension, clinical suspicion is very important. An early diagnosis and the initiation of an adequate antihypertensive treatment, which allows the patient to undergo surgery with normal blood pressure, ensure a cure in most cases if tumor resection is complete.

Pheochromocytoma and paraganglioma at a children's hospital in Argentina. A case series. / Feocromocitoma y paraganglioma en un hospital pediátrico de Argentina. Serie de casos.

Pheochromocytomas and paragangliomas are neuroendocrine tumors producing catecholamines. Pheochromocytomas occur in the adrenal medulla, while paragangliomas are those that occur outside the adrenal gland. Here we describe a case series of children with a pathological diagnosis of pheochromocytoma or paraganglioma who consulted at a tertiary care children's hospital in Argentina. A total of 21 patients (14 males) were included; their median age was 11.4 years; 8 children had pheochromocytoma and 13, paraganglioma. Arterial hypertension was observed in 14/21. Most paragangliomas were para-aortic (9/13). Since they are a potentially curable cause of hypertension, clinical suspicion is very important. An early diagnosis and the initiation of an adequate antihypertensive treatment, which allows the patient to undergo surgery with normal blood pressure, ensure a cure in most cases if tumor resection is complete.

El feocromocitoma y el paraganglioma son tumores neuroendocrinos secretores de catecolaminas. Los feocromocitomas se originan en la médula suprarrenal, mientras que los paragangliomas son extraadrenales. Se describe una serie de casos de niños con diagnóstico anatomopatológico de feocromocitoma o paraganglioma que consultaron en un hospital pediátrico de alta complejidad de Argentina. Se incluyeron 21 pacientes, 14 varones, con una mediana de edad de 11,4 años; 8 casos con feocromocitoma y 13 casos con paraganglioma. Se presentaron con hipertensión arterial 14/21. La mayoría de los paragangliomas tuvieron localización paraaórtica (9/13). Debido a que representan una causa potencialmente curable de hipertensión arterial, la sospecha clínica es muy importante. El diagnóstico temprano y la instauración de un tratamiento antihipertensivo adecuado, que permita afrontar la cirugía con normotensión arterial, aseguran la curación en la mayoría de los casos si la resección tumoral es completa.

The Pheochromocytoma/Paraganglioma syndrome: an overview on mechanisms, diagnosis and management.

Pheochromocytomas/paragangliomas (PPGL) are rare, metastatic, and potentially fatal neuroendocrine tumors, often neglected because they present symptoms similar to other prevailing clinical conditions such panic syndrome, thyrotoxicosis, anxiety, hypoglycemia, etc., delaying diagnosis and treatment. The rate of diagnosis of PPGL has been increasing with the improvement in the measurement of catecholamine metabolites and the expanding availability of imaging procedures. Its essential genetic nature has been extensively investigated, comprising more than 20 genes currently related to PPGL and more new genes will probably be revealed. This overview will shed some light on the clinical, laboratory, topographical, genetic diagnosis, and management of PPGL.

Oncocytic Lipoadenoma: Report of 3 Rare Cases Involving the Parotid Gland, Including a Synchronous Presentation With Paraganglioma of the Right Carotid Bifurcation and Literature Review.

Oncocytic lipoadenoma (OL) is a rare salivary gland tumor characterized by the presence of oncocytic cells and mature adipose tissue. To date, only 30 cases of OL have been reported in the English-language literature. We present 3 additional OL cases involving the parotid, including a synchronous presentation with paraganglioma of the right carotid bifurcation. Microscopically, both the OLs were composed of a mixed population of oncocytes and adipocytes in varying proportions surrounded by a thin, connective tissue fibrous capsule. Oncocytes were positive for pan-cytokeratins (CKs) AE1/AE3, epithelial membrane antigen, CK5, CK7, CK14, CK18, and CK19. Calponin, p63, alpha-smooth muscle actin, and carcinoembryonic antigen were negative. Vimentin and S-100 protein were positive only in adipose cells. Despite distinctive morphologic features, OL is often misdiagnosed, given its rarity. We hope to contribute to surgeons' and pathologists' awareness and knowledge regarding the existence of this tumor and provide adequate management through conservative surgical excision.

Endolymphatic Sac Tumour: A Case Report and Review of the Literature

Introduction Endolymphatic sac tumor (ELST) is a slow-growing, low-grade, locallyinfiltrative tumor arising from the endolymphatic sac/duct, which is located in the posterior part of the petrous temporal bone. It may be sporadic in origin, or may be associated with Von-Hippel Lindau (VHL) syndrome. Case description A 40-year-old female patient with an ELST without VHL syndrome who was treated successfully by microsurgical extirpation of the tumor. Discussion We discuss the radiological features and the histopathology of this rare tumor and review the relevant literature. Conclusion The case herein reported adds to the previously-reported cases of this rare tumor.

Multidisciplinary practice guidelines for the diagnosis, genetic counseling and treatment of pheochromocytomas and paragangliomas.

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors that arise from chromaffin cells of the adrenal medulla and the sympathetic/parasympathetic neural ganglia, respectively. The heterogeneity in its etiology makes PPGL diagnosis and treatment very complex. The aim of this article was to provide practical clinical guidelines for the diagnosis and treatment of PPGLs from a multidisciplinary perspective, with the involvement of the Spanish Societies of Endocrinology and Nutrition (SEEN), Medical Oncology (SEOM), Medical Radiology (SERAM), Nuclear Medicine and Molecular Imaging (SEMNIM), Otorhinolaryngology (SEORL), Pathology (SEAP), Radiation Oncology (SEOR), Surgery (AEC) and the Spanish National Cancer Research Center (CNIO). We will review the following topics: epidemiology; anatomy, pathology and molecular pathways; clinical presentation; hereditary predisposition syndromes and genetic counseling and testing; diagnostic procedures, including biochemical testing and imaging studies; treatment including catecholamine blockade, surgery, radiotherapy and radiometabolic therapy, systemic therapy, local ablative therapy and supportive care. Finally, we will provide follow-up recommendations.

The North American Neuroendocrine Tumor Society Consensus Guidelines for Surveillance and Management of Metastatic and/or Unresectable Pheochromocytoma and Paraganglioma.

ABSTRACT: This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the medical management and surveillance of metastatic and unresectable pheochromocytoma and paraganglioma held on October 2 and 3, 2019. The panelists consisted of endocrinologists, medical oncologists, surgeons, radiologists/nuclear medicine physicians, nephrologists, pathologists, and radiation oncologists. The panelists performed a literature review on a series of questions regarding the medical management of metastatic and unresectable pheochromocytoma and paraganglioma as well as questions regarding surveillance after resection. The panelists voted on controversial topics, and final recommendations were sent to all panel members for final approval.

A case of orbital extra-adrenal paraganglioma in a quarter horse

Paragangliomas are tumors originating from paraganglia cells which represent a considerable constituent of the dispersed neuroendocrine system. Rarely these tumors are found within the orbital region. This report documents a case of primary extra-adrenal paraganglioma in a 15-year-old female quarter horse, diagnosed on the basis of clinical signs, gross anatomopathological, histopathological and immunohistochemical investigations. Clinical diagnostics led to full appreciation of the severe tumor invasiveness and to an informed decision by the owner for euthanasia. Gross inspection confirmed the previous clinical assessments of exophthalmos consequential to pressure from the orbital neoplasia, revealing a mass infiltrating into surrounding tissues. Histopathology and immunohistochemistry allowed for the final diagnosis of paraganglioma. Histology sections showed a partially encapsulated infiltrative mass with multifocal angiotropic growth, and composed of polygonal cells organized in nests, packets, and bundles supported by a fibrovascular stroma. The lobules were lined peripherally by spindle cells. The tumor was highly vascular with blood-filled lacunae and multifocal to coalescing areas of liquefactive necrosis. The polygonal cells were characterized by indistinct borders, lightly eosinophilic cytoplasm with moderate amount of granules, round or oval central nuclei with stippled chromatin (“salt and pepper” appearance) and inconspicuous nucleoli. Immunohistochemistry aided in the diagnostic discrimination of paraganglioma from neuroendocrine carcinoma and in the assessment of tumor differentiation. Orbital paraganglioma holds low likelihood for animal survival, but may have good prognosis when timely addressed.

A case of orbital extra-adrenal paraganglioma in a quarter horse

Paragangliomas are tumors originating from paraganglia cells which represent a considerable constituent of the dispersed neuroendocrine system. Rarely these tumors are found within the orbital region. This report documents a case of primary extra-adrenal paraganglioma in a 15-year-old female quarter horse, diagnosed on the basis of clinical signs, gross anatomopathological, histopathological and immunohistochemical investigations. Clinical diagnostics led to full appreciation of the severe tumor invasiveness and to an informed decision by the owner for euthanasia. Gross inspection confirmed the previous clinical assessments of exophthalmos consequential to pressure from the orbital neoplasia, revealing a mass infiltrating into surrounding tissues. Histopathology and immunohistochemistry allowed for the final diagnosis of paraganglioma. Histology sections showed a partially encapsulated infiltrative mass with multifocal angiotropic growth, and composed of polygonal cells organized in nests, packets, and bundles supported by a fibrovascular stroma. The lobules were lined peripherally by spindle cells. The tumor was highly vascular with blood-filled lacunae and multifocal to coalescing areas of liquefactive necrosis. The polygonal cells were characterized by indistinct borders, lightly eosinophilic cytoplasm with moderate amount of granules, round or oval central nuclei with stippled chromatin (“salt and pepper” appearance) and inconspicuous nucleoli. Immunohistochemistry aided in the diagnostic discrimination of paraganglioma from neuroendocrine carcinoma and in the assessment of tumor differentiation. Orbital paraganglioma holds low likelihood for animal survival, but may have good prognosis when timely addressed.(AU)

Primary malignant tumors of the adrenal glands.

Malignancy must be considered in the management of adrenal lesions, including those incidentally identified on imaging studies. Adrenocortical carcinomas (ACCs) are rare tumors with an estimated annual incidence of 0.7-2 cases per year and a worldwide prevalence of 4-12 cases per million/year. However, a much higher incidence of these tumors (>15 times) has been demonstrated in south and southeastern Brazil. Most ACCs cause hypersecretion of steroids including glucocorticoids and androgens. ACC patients have a very poor prognosis with a 5-year overall survival (OS) below 30% in most series. Pheochromocytoma or paraganglioma (PPGL) is a metabolically active tumor originating from the chromaffin cells of the adrenal medulla. The incidence of PPGL is 0.2 to 0.9 cases per 100,000 individuals per year. Pheochromocytomas are present in approximately 4-7% of patients with adrenal incidentalomas. Classically, PPGL manifests as paroxysmal attacks of the following 4 symptoms: headaches, diaphoresis, palpitations, and severe hypertensive episodes. The diagnosis of malignant PPGL relies on the presence of local invasion or metastasis. In this review, we present the clinical and biochemical characteristics and pathogenesis of malignant primary lesions that affect the cortex and medulla of human adrenal glands.

Primary malignant tumors of the adrenal glands

Malignancy must be considered in the management of adrenal lesions, including those incidentally identified on imaging studies. Adrenocortical carcinomas (ACCs) are rare tumors with an estimated annual incidence of 0.7-2 cases per year and a worldwide prevalence of 4-12 cases per million/year. However, a much higher incidence of these tumors (>15 times) has been demonstrated in south and southeastern Brazil. Most ACCs cause hypersecretion of steroids including glucocorticoids and androgens. ACC patients have a very poor prognosis with a 5-year overall survival (OS) below 30% in most series. Pheochromocytoma or paraganglioma (PPGL) is a metabolically active tumor originating from the chromaffin cells of the adrenal medulla. The incidence of PPGL is 0.2 to 0.9 cases per 100,000 individuals per year. Pheochromocytomas are present in approximately 4-7% of patients with adrenal incidentalomas. Classically, PPGL manifests as paroxysmal attacks of the following 4 symptoms: headaches, diaphoresis, palpitations, and severe hypertensive episodes. The diagnosis of malignant PPGL relies on the presence of local invasion or metastasis. In this review, we present the clinical and biochemical characteristics and pathogenesis of malignant primary lesions that affect the cortex and medulla of human adrenal glands.

Tumor de corpo carotídeo (paraganglioma): relato de dois casos submetidos a tratamento cirúrgico / Carotid body tumor (paraganglioma): report of two cases treated surgically

O tumor de corpo carotídeo é uma neoplasia rara, geralmente benigna, que acomete, sobretudo, indivíduos entre a quarta e a quinta décadas de vida. Manifesta-se pela presença de massa cervical consistente localizada abaixo do ângulo da mandíbula, pulsátil e comumente indolor. Pode evoluir para dor local, disfagia, soluços, rouquidão e síndrome do corpo carotídeo hipersensível. Este artigo relata os casos de duas pacientes diagnosticadas com essa neoplasia e submetidas ao tratamento cirúrgico. A primeira foi submetida a uma ressecção em bloco do tumor, enquanto a segunda, com estadiamento mais precoce, foi tratada com uma ressecção subadventicial da lesão.

A carotid body tumor is a rare neoplasm, generally benign, that predominantly affects people between their fourth and fifth decades of life. It manifests as a pulsatile and generally painless cervical mass with firm consistency, located below the angle of the jaw. It can progress to the extent that it causes localized pain, dysphagia, hiccups, hoarseness and hypersensitive carotid body syndrome. This article reports the cases of two female patients diagnosed with this tumor who were treated surgically. The first was treated with block resection of the tumor, while the second patient, who had an early stage tumor, was treated with subadventitial resection of the lesion.

Manejo clínico y quirúrgico de los feocromocitomas y paragangliomas / Clinical and surgical management of pheochromocytomas and paragangliomas

Los feocromocitomas y paragangliomas (Feo/PGL) son tumores neurendocrinos raros con diferentes presentaciones clínicas, asociados a alta morbimortalidad. Reconocer los signos y síntomas es el paso diagnóstico inicial. Las metanefrinas fraccionadas urinarias tienen una excelente sensibilidad y especificidad. La tomografía computarizada (TC) es el método de elección para su localización. La tomografía por emisión de positrones (PET) con F18-fluordeoxiglucosa (F18-FDG) es el método funcional recomendado para detectar metástasis. La resección quirúrgica constituye la única opción curativa en estos pacientes. La adrenalectomía laparoscópica es la vía de abordaje para la mayoría los Feo/PGL. El tratamiento farmacológico, 7 a 14 días previos con alfabloqueantes y betabloqueantes, tiene como objetivo normalizar la presión arterial y prevenir complicaciones cardiovasculares periquirúrgicas. Se conoce que al menos un tercio de los pacientes presentan una mutación genética germinal. El estudio genético debe estar orientado a las características sindrómicas, formas de presentación, localización y fenotipo bioquímico del tumor. Se recomienda el abordaje interdisciplinario en centros especializados con experiencia en esta patología poco frecuente. (AU)

Pheochromocytomas and paragangliomas are rare neuroendocrine tumors with different clinical manifestation associated with high morbidity and mortality. Recognize signs and symptoms is the first step in diagnosis. Urinary fractionated metanephrines have an excellent specificity and sensitivity. Computed Tomography (CT) is the first-choice imaging modality for location. F18-DG positron tomography (PET)/CT scanning is the functional modality of choice for metastatic disease. Surgery is the only curative treatment. Minimally invasive adrenalectomy is the surgical approach for most adrenal pheochromocytomas. Perioperative alpha and beta blockade for 7 to 14 days normalize blood pressure and prevent perioperative cardiovascular complications. Is recognize that at least one-third of the patients have disease-causing germline mutations. Genetic testing must be orientated to syndromic features, presentation, localization and biochemical profile of these tumors. Multidisciplinary teams at centers with appropriate expertise are recommended to ensure a favorable outcome. (AU)

Actualización del manejo diagnóstico y terapéutico del paraganglioma / Update on diagnostic and therapeutic management of paraganglioma

El paraganglioma es un tumor neuroendocrino poco frecuente que puede desarrollarse en diversos sitios del organismo. Alrededor del 97 por ciento son benignos y se curan mediante la extirpación quirúrgica, y el restante 3 por ciento son malignos, y provocar metástasis a distancia. Alrededor del 75 por ciento son esporádicos y el restante 25 por ciento son hereditarios (y tienen una mayor probabilidad de ser múltiples y de desarrollo a una edad temprana). Pueden tener predisposición genética asociada a síndromes tumorales familiares, como la neoplasia endocrina múltiple tipo 2, el síndrome de Von Hippel-Lindau y la neurofibromatosis tipo 1, o mutaciones específicas relacionadas solamente con el desarrollo de paragangliomas. Comparado con la forma de aparición esporádica, la presentación familiar tiene tendencia a aparecer en edades más jóvenes, y a tener múltiple localización. Por la poca disponibilidad de recursos y lo costoso de las investigaciones utilizadas, son de difícil diagnóstico en nuestro medio, por lo cual no se excluye que exista un subregistro en el número de casos que se puedan presentar, razón por la que es importante siempre -ante la sospecha clínica- pensar en su probable confirmación diagnóstica y situación. Los estudios de imágenes y la medición de la producción no fisiológica de catecolaminas, pueden ayudar en el diagnóstico de esta entidad. Las principales modalidades de tratamiento son: la cirugía, la embolización y la radioterapia. Con el objetivo de actualizar y sugerir una guía de tratamiento se realizó la presente revisión(AU)

Paraganglioma is a rare neuroendocrine tumor that may occur in several parts of the body. Roughly 97 percent of these tumors are benign and can be excised through surgery whereas 3 percent of them are malignant and cause distant metastasis. Almost 75 percent are sporadic and the remaining 25 percent are hereditary (more likely to be multiple and developed at early ages). They may be genetically predisposed and associated to family tumor syndromes such as type 2 multiple endocrine neoplasia, Von Hippel-Lindau syndrome and type 1 neurofibromatosis or specific mutations related to development of paragangliomas. When compared to the sporadic occurrence, the family presentation tends to appear at younger ages, with multiple locations. Owing to the low resource availability and the high cost of research, these tumors are difficult to be diagnosed in our conditions, so there may be failures in registering the real number of cases; this is the reason why it is always important to think on possible diagnostic confirmation when clinical suspicion of paraganglioma arises. Imaging studies and measurement of the non-physiological production of catecholamines may help in the diagnosis of this disease. The main therapeutical modalities are surgery, embolization and radiotherapy. The present review was intended to update this topic and to submit a treatment guideline(AU)

Actualización del manejo diagnóstico y terapéutico del paraganglioma / Update on diagnostic and therapeutic management of paraganglioma

El paraganglioma es un tumor neuroendocrino poco frecuente que puede desarrollarse en diversos sitios del organismo. Alrededor del 97 por ciento son benignos y se curan mediante la extirpación quirúrgica, y el restante 3 por ciento son malignos, y provocar metástasis a distancia. Alrededor del 75 por ciento son esporádicos y el restante 25 por ciento son hereditarios (y tienen una mayor probabilidad de ser múltiples y de desarrollo a una edad temprana). Pueden tener predisposición genética asociada a síndromes tumorales familiares, como la neoplasia endocrina múltiple tipo 2, el síndrome de Von Hippel-Lindau y la neurofibromatosis tipo 1, o mutaciones específicas relacionadas solamente con el desarrollo de paragangliomas. Comparado con la forma de aparición esporádica, la presentación familiar tiene tendencia a aparecer en edades más jóvenes, y a tener múltiple localización. Por la poca disponibilidad de recursos y lo costoso de las investigaciones utilizadas, son de difícil diagnóstico en nuestro medio, por lo cual no se excluye que exista un subregistro en el número de casos que se puedan presentar, razón por la que es importante siempre -ante la sospecha clínica- pensar en su probable confirmación diagnóstica y situación. Los estudios de imágenes y la medición de la producción no fisiológica de catecolaminas, pueden ayudar en el diagnóstico de esta entidad. Las principales modalidades de tratamiento son: la cirugía, la embolización y la radioterapia. Con el objetivo de actualizar y sugerir una guía de tratamiento se realizó la presente revisión(AU)

Paraganglioma is a rare neuroendocrine tumor that may occur in several parts of the body. Roughly 97 percent of these tumors are benign and can be excised through surgery whereas 3 percent of them are malignant and cause distant metastasis. Almost 75 percent are sporadic and the remaining 25 percent are hereditary (more likely to be multiple and developed at early ages). They may be genetically predisposed and associated to family tumor syndromes such as type 2 multiple endocrine neoplasia, Von Hippel-Lindau syndrome and type 1 neurofibromatosis or specific mutations related to development of paragangliomas. When compared to the sporadic occurrence, the family presentation tends to appear at younger ages, with multiple locations. Owing to the low resource availability and the high cost of research, these tumors are difficult to be diagnosed in our conditions, so there may be failures in registering the real number of cases; this is the reason why it is always important to think on possible diagnostic confirmation when clinical suspicion of paraganglioma arises. Imaging studies and measurement of the non-physiological production of catecholamines may help in the diagnosis of this disease. The main therapeutical modalities are surgery, embolization and radiotherapy. The present review was intended to update this topic and to submit a treatment guideline(AU)