Head and neck paragangliomas: clinical and molecular genetic classification

Head and neck paragangliomas are tumors arising from specialized neural crest cells. Prominent locations are the carotid body along with the vagal, jugular, and tympanic glomus. Head and neck paragangliomas are slowly growing tumors, with some carotid body tumors being reported to exist for many years as a painless lateral mass on the neck. Symptoms depend on the specific locations. In contrast to paraganglial tumors of the adrenals, abdomen and thorax, head and neck paragangliomas seldom release catecholamines and are hence rarely vasoactive. Petrous bone, jugular, and tympanic head and neck paragangliomas may cause hearing loss. The internationally accepted clinical classifications for carotid body tumors are based on the Shamblin Class I-III stages, which correspond to postoperative permanent side effects. For petrous-bone paragangliomas in the head and neck, the Fisch classification is used. Regarding the molecular genetics, head and neck paragangliomas have been associated with nine susceptibility genes: NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, SDHAF2 (SDH5), and TMEM127. Hereditary HNPs are mostly caused by mutations of the SDHD gene, but SDHB and SDHC mutations are not uncommon in such patients. Head and neck paragangliomas are rarely associated with mutations of VHL, RET, or NF1. The research on SDHA, SDHAF2 and TMEM127 is ongoing. Multiple head and neck paragangliomas are common in patients with SDHD mutations, while malignant head and neck paraganglioma is mostly seen in patients with SDHB mutations. The treatment of choice is surgical resection. Good postoperative results can be expected in carotid body tumors of Shamblin Class I and II, whereas operations on other carotid body tumors and other head and neck paragangliomas frequently result in deficits of the cranial nerves adjacent to the tumors. Slow growth and the tendency of hereditary head and neck paragangliomas to be multifocal may justify less aggressive treatment strategies.

Tumor de cuerpo carotídeo / Carotid body tumor

Carotid body tumors (paragangliomas) are very rare, highly vascularized and usually benign tumors, originated in the carotid body chemoreceptors. We present the cases of two asymptomatic patients referred for left cervical mass; preoperative study was CT and CT angiography, respectively, which are consistent with carotid body tumors. The tumors were completely removed by subadventitial disection without complications; the biopsy was compatible with paraganglioma. No evidence of recurrence could be found.

Los tumores de cuerpo carotídeo (paragangliomas) son neoplasias altamente vascularizadas, muy poco frecuentes y generalmente benignas, originadas en los quimiorreceptores del cuerpo carotídeo. Se presentan los casos de dos pacientes derivados por aumento de volumen cervical izquierdo, asintomáticos, con estudio preoperatorio realizado por TAC y angiografía por TAC, respectivamente, que resultan compatibles con tumores de cuerpo carotídeo. Se resuelven quirúrgicamente, mediante disección subadventicial, informando la biopsia paraganglioma. Los tumores fueron completamente removidos, sin evidencia de recurrencia y sin mayores complicaciones.

Tumor de glomus carotídeo, a propósito de un caso / Carotid body tumor: a case report

Se presenta el caso clínico de un tumor de glomus carotídeo en una mujer de 27 años que debutó con un aumento de volumen cervical derecho. El estudio con tomografía computada en fase angiográfica (Angio TC) demostró un tumor heterogéneo a nivel de la bifurcación carotídea que provocaba efecto de masa desplazando, pero no infiltrando los vasos carotídeos. Se realizó la extirpación completa del tumor con diseccion subadventicial, durante la cual fue necesaria la ligadura de la arteria carótida externa distal al nacimiento de la arteria tiroídea superior. El informe histopatológico concluyó tumor de glomus carotídeo con áreas de necrosis y pleomorfismo celular. Se realizó una revisión de la literatura nacional e internacional sobre esta infrecuente enfermedad.

A importância da embolização pré-operatória no tratamento do tumor do corpo carotídeo: relato de caso e revisão da literatura / The importance of preoperative embolization for the treatment of the carotid body tumor: case report and review of the literature

Os tumores do corpo carotídeo são neoplasias raras, que se originam dos pequenos órgãos quimio e barorreceptores localizados na adventícia da bifurcação da artéria carótida comum. Constituem-se uma doença de grande interesse para o cirurgião vascular, na medida em que crescem aderidos à adventícia dos vasos que compõem essa bifurcação. Por isso, sua cirurgia requer não só o conhecimento anatômico da região, mas também perfeito reconhecimento das técnicas de reconstrução vascular. Representam um problema especial quanto a seu manejo, devido à sua rica vascularização e intimidade com estruturas nobres da região cervical, como nervos e grandes vasos. Neste caso, apresentamos um homem com um tumor de corpo carotídeo aderido à carótida direita, diagnosticado por punção biópsia e tratado em dois tempos, sendo o primeiro por tratamento endovascular, realizando embolização percutânea do tumor, e, no segundo, a ressecção cirúrgica do mesmo, o que evidencia o tratamento combinado, segundo atual literatura.

Carotid body tumors are rare neoplasms originating from the small chemo- and baroreceptors located in the adventitia of the common carotid artery bifurcation. They are a disease of great interest for vascular surgeons, given that they grow adhered to the adventitia of vessels comprising this bifurcation. For that, their surgery requires not only anatomical knowledge of the region, but also perfect familiarization with vascular repair techniques. Carotid body tumors are a particular problem as to their management, due to rich vascularization and intimacy with important structures of the cervical region, such as nerves and large vessels. We report on a male patient with carotid body tumor adhered to the right carotid artery, diagnosed by puncture biopsy and treated at two different time periods: first by endovascular treatment, with percutaneous embolization of the tumor; and later by surgical resection, which represents the combined treatment suggested in the current literature.

Paragangliomas de cabeza y cuello / Parangangliomas of the head and neck

Los parangangliomas son tumores altamente vascularizados que se originan de células provenientes de la cresta neural. El tratamiento de elección es la resección quirúrgica completa, lo cual se ve dificultado por su abundante irrigación y por su estrecha relación anatómica con importantes estructuras vásculo-nerviosas. En el presente estudio se revisa retrospectivamenete la experiencia del Departamento de Otorrinolaringología de Clínica Las Condes en el manejo quirúrgico de estas neoplasias. Entre los años 1998 y 2003 se trataron 5 pacientes portadores de paragangliomas de cabeza y cuello: un glomus yugular (GY), 2 glomus carotídeo (GC) y 2 glomus timpánicos (GT). El estudio imagenológico consistió en tomografía computarizada (TC) para todos los casos, complementada con resonancia nuclear magnética (RNM) y/o angiografía en algunos pacientes. El abordaje quirúrgico fue el indicado para cada lesión: timpanotomía retroauricular (GT), cervicotomía (GC) y abordaje infratemporal tipo A de Fisch (GY). En todos se logró una resección tumoral completa, sin presentarse complicaciones perioperatorias de consideración ni recurrencias hasta la fecha. Contando con un adecuado estudio imagenológico y una cuidadosa planificación quirúrgica, la resección de los paragangliomas de cabeza y cuello puede realizarse con un bajo índice de complicaciones, reservando la radioterapia como alternativa terapéutica únicamente en aquellos casos inoperables.

Approach to surgical management of carotid body tumor and our experience at Assiut University Hospital

Carotid body tumor [CBT] is a rare neoplasm, which typically presents as a slow growing, painless neck mass found along the anterior border of the sternocleidomastoid muscle. This tumor is generally benign but possesses aggressive resection remains a surgical challenge traditionally associated with a 15-30% incidence of cranial nerve injury. To present our experience at Assiut University Hospital regarding surgery of CBT and the use of preoperative embolization and mandibulotomy in large sized tumors. The study was performed on 18 cases with CBT, 5 females and 13 males with a mean age of 40 years. Clinical and radiological diagnosis was recorded. Angiography was done in 17 cases for confirmation of CBT diagnosis and its extent, evaluation of carotid arteries and for preoperative emobilization. One case due to some technical difficulties was evaluated by spiral CT angiography. Patients were classified according to the tumor size and Shamblin classification. Preoperative imobilization to decrease the tumor vascularity and the intraoperative blood loss, was done. Patients were subjected to surgical removal of the tumor through anterior longitudinal approach to the carotid system not later than 4 days after the embolization to avoid the inflammatory phase and the development of any collaterals. Paramedian mandibulotomy was done in cases with very large tumore. Patttients presented with painless swelling, local tenderness, bruit, difficulty with swallowing, and hoarseness. Preoperative embolizaiton for large cases decreases the tumor vascularity by [25% to 45%][as documented by post embolization films. The average blood replacement was one unit. There were no deaths and complications were recorded in 44.4% of patients as vascular complications [legation of external carotid artery, simple repair of internal carotid artery, and repair of internal carotid artery with interposition of vein graft] or neurological complications as cerebrovascular stroke, injury of vagus, hypoglossal and marginal mandibular nerves. All cases were confirmed histologically as benign paragangliomas. CBT should be taken in considerations in all lateral neck masses. Angiograhy is very helpful in making the diagnosis. Preoperative embolizaiton decreases the tumor size, the vascularity and facilitates the subsequent surgery. Paramedian mandibulotomy provided a wide exposure, in cases with large sized tumors. Early detection and resection of smaller tumors ultimately reduced the risk of complications

Paragangliomas del cuerpo carotideo / Carotid body paragangliomas

Los paragangliomas son neoplasias derivadas de la cresta neural, benignas en un alto porcentaje y poco comunes. En la cabeza y cuello, los del cuerpo carotídeo, son los de mayor incidencia. Por lo general, se presentan como una masa asintomática y ocurren en personas entre la cuarta y quinta década de la vida. Su aparición se ha relacionado con la vida en las grandes alturas o con enfermedad pulmonar obstructiva crónica (hipoxia crónica), y existe un grupo con tendencia familiar. Las técnicas de imágenes diagnósticas no invasivas (resonancia magnética, tomografía computarizada, gammagrafía) son los instrumentos ideales para confirmar el diagnóstico. La cirugía se considera la única manera de tratamiento para lograr su curación. En grandes tumores, todavía existe morbilidad de tipo neurovascular durante la extirpación quirúrgica. Para reducir la misma, se ha preconizado la embolización arterial preoperatoria

Tratamiento quirúrgico de las lesiones carotídeas / Surgical treatment for carotid lesions

Se presenta una serie de 98 cirugías carotídeas, 93 endarterectomías y cinco resecciones de tumores del cuerpo carotídeo. La serie de 93 endarterectomías se comparó con dos informes recientes de la literatura; se analizaron 16 variables y se obtuvo una correlación estadística mediante la t de Student en cada una de ellas. Se encontraron diferencias estadísticamente significativas en: número de enfermos y tipo de seguimiento, indicaciones quirúrgicas (en nuestra serie más de 90 por ciento de las operaciones se efectuaron en enfermos con lesiones sintomáticas, en comparación con lo informado, en donde hubo 40 por ciento de enfermos con lesiones asintomáticas). En nuestra serie se utilizó una derivación, selectiva. Las cifras de morbimortalidad y los resultados a largo plazo fueron similares con otros estudios revisados. En la discusión se analiza la literatura reciente al respecto. Los tumores del cuerpo carotídeo, aunque poco frecuentes, constituyen un reto para su tratamiento. Se discute la técnica quirúrgica utilizada (resección subadventicia), ya que ésta simplifica su resección y disminuye el porcentaje de complicaciones