Contemporary management of carotid body tumors in a Midwestern academic center.

BACKGROUND: Carotid body tumors are rare, neurogenic tumors arising from the periadventitial chemoreceptive tissue of the carotid body. The purpose of this study is to ascertain the presentation and preoperative risk factors associated with surgical resection. METHODS: A single-center retrospective review of 25 carotid body tumor resections from 2002 to 2019. Demographics, periprocedural details, and postoperative outcomes were analyzed using Stata (Stata Corporation, College Station, TX). RESULTS: Among 25 patients, 64% were women, 84% were asymptomatic, and the mean age was 49 years (range 21-79). Forty-four percent of tumors were Shamblin III. Nine patients underwent preoperative embolization but did not correlate with decreased blood loss (299 cm3 vs 205 cm3, P = .35). The 30-day death, stroke, and cranial nerve injury rates were 0%, 8%, and 32%, respectively. Cranial nerve injuries included 20% vagus, 4% hypoglossal, 4% facial, and 4% glossopharyngeal, with permanent deficits in 4% (n = 1). Mean length of stay was 3.0 days (range 1-9 days). At a mean follow-up of 12 months (range 1-63 months), there has been no recurrence. CONCLUSION: Although carotid body tumors are uncommon in the Midwest, complete surgical resection is curative of these typically hormonally inactive tumors. Preoperative embolization did not affect blood loss, and the incidence of death, stroke, and permanent cranial nerve injury rates remained very low.

SDHD gene mutation in Mexican population whit carotid body tumor. / Mutación del gen SDHD en población mexicana con tumor del cuerpo carotídeo

Introduction: Among the U.S. population, the p81L SDHD (11q23) gene mutation is present in 6-36% of patients with sporadic carotid body tumor (CBT), but in familial cases is high as 80%. That is why the P81L mutation is used as a screening method for carotid body tumor in the U.S. Methods: We included 25 patients who underwent resection of a CBT from January 2010 to June 2015. After informed consent, a blood sample was taken for genetic testing on real-time polymerase chain reaction, in order to identify p81L mutation in the SDHD gene. The information was analyzed with descriptive statistics, using central tendency and description measures. Results: In our group, 92% were females, a mean age of 55.5 years, and 52% were Shamblin type II. The most common place of residence was Mexico City, 8% of the patients had family history, about 20% of the patients had a contralateral tumor and 16% had antecedent of another kind of tumor, 4 (16%) p81L SDHD gene mutations were detected, all of them were heterozygous. Conclusions: The p81L mutation in the SDHD gene was found in the Mexican population in higher grade that in the U.S. population, which explain the high incidence of this pathology in our country, but we need more studies about this subject.

Introducción: La mutación p81L del gen SDHD (11q23) se encuentra presente en el 6-36% de los pacientes con tumores del cuerpo carotídeo (TCC) esporádicos y hasta en el 80% de los que presentan TCC familiares. En los EE.UU. se usa como método de cribado para TCC. Método: Se incluyeron 25 pacientes consecutivos operados de resección de TCC entre enero de 2010 y junio de 2015. Se les tomó muestra sanguínea venosa que se sometió a reacción en cadena de la polimerasa en tiempo real para identificar la mutación p81L del gen SDHD (11q23). La información se analizó con estadística descriptiva mediante medidas de tendencia central y dispersión. Resultados: Del grupo en estudio, el 92% eran mujeres, la edad promedio era de 55.5 años y el 52% tenían tumor Shamblin tipo II. El lugar de residencia más frecuente fue la Ciudad de México. El 8% presentaban antecedentes familiares, el 20% tumor bilateral y el 16% presentaron un tumor en otra región. Se encontró la mutación p81L del gen SDHD (11q23) en el 16% de los pacientes de forma heterocigota. Conclusiones: La mutación p81L del gen SDHD se encuentra presente en la población mexicana en un grado más elevado que lo reportado en los EE.UU., lo que podría explicar la alta incidencia en nuestro medio.

[Individualized treatment of bilateral carotid body tumor].

Objective: To investigate individualized therapeutic strategy for bilateral carotid body tumors. Methods: Clinical data of 16 patients with bilateral carotid body tumor treated from January 2003 to August 2016 were retrospectively studied. Of the 16 patients, 9 were males and 7 were females; 5 were sporadic and 11 were familial; 8 cases were observed, 1 cases was malignant and treated with chemotherapy, and 7 cases were treated with surgery. The treatment course, perioperative complications and clinical efficacy were assessed. Comprehensive evaluation of bilateral carotid body tumors was performed based on the size of bilateral tumor, clinical manifestations, genetic tests and other indicators. Individual treatment strategies included observation, surgery and observation, bilateral surgery, radiotherapy or chemotherapy. Surgical resection of carotid body tumor was unilateral in 3 cases and bilateral in 3 cases; removal of bilateral carotid body tumors plus unilateral jugular bulb in 1 case; and the internal carotid artery was reconstructed with autologous greater saphenous vein in 1 case. Results: All patients were followed up for 3 months to 12 years. There was no patient death during perioperative period. Superior laryngeal nerve injury occurred in 2 case. Baroreceptor failure syndrome occurred in one patient, but it gradually recoverd with medical treatments. Conlusion: It is important to identify whether bilateral carotid body tumors are hereditary and to make an individualized therapeutic strategy for each patient with bilateral carotid body tumors, focusing on the improvement in the quality of life of patient.

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.

Mutation of SDHB is a cause of hypoxia-related high-altitude paraganglioma.

PURPOSE: Paragangliomas of the head and neck are neuroendocrine tumors and are associated with germ line mutations of the tricarboxylic acid cycle-related genes SDHB, SDHC, SDHD, and SDHAF2. Hypoxia is important in most solid tumors, and was directly implicated in tumorigenesis over 40 years ago when it was shown that dwelling at high altitudes increases the incidence of carotid body hyperplasia and paragangliomas. Although recent research has now elucidated several pathways of hypoxia in paragangliomas, nothing is currently known of the genetics or of gene-environment interactions in high-altitude paraganglioma. We postulated that SDH mutations might play a role in these tumors. EXPERIMENTAL DESIGN: Patients from a Mexican family, originating and resident in Guadalajara, were tested for mutations of SDHD, and subsequently, for mutations of SDHB followed by immunohistochemical confirmation of SDHB loss. RESULTS: Two patients, born and resident at altitudes of between 1,560 and 2,240 m, were found to have head and neck paragangliomas, including a remarkably aggressive recurrent tumor. Mutation analysis identified a pathogenic missense mutation in exon 7 of SDHB, c.689G>A, p.Arg230His, and loss of the SDHB protein was confirmed by immunohistochemistry. CONCLUSIONS: This is the first report of a SDH gene mutation in paraganglioma at high altitude. A rapidly recurrent head and neck paraganglioma is a very rare finding in an SDH mutation carrier, suggesting a gene-environment interaction. Neither patient showed evidence of sympathetic paraganglioma.

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.

Current concepts for the surgical management of carotid body tumor.

BACKGROUND: Carotid body tumor (CBT) is a rare lesion of the neuroendocrine system. Chronic hypoxia has long been recognized as an etiology of CBT and other paragangliomas. Recent biogenetic discoveries reveal that mutations in oxygen-sensing genes are another etiology, accounting for approximately 35% of cases, and that these 2 etiologies are probably additive. DATA SOURCES: (1) A retrospective analysis of fifteen cases of CBT in a 6-year period occurring in the mountains of Southern Appalachia; (2) an extensive review of the literature on the surgery of CBT and on the expansive biogenetic understanding of the disease. CONCLUSIONS: Improved imaging, vascular surgical techniques, and understanding of the disease have vastly improved outcomes for patients. The necessities for long-term follow-up and appropriate genetic testing and counseling of patients and their families are documented. Surgeon and institutional competence are critical in achieving maximal outcomes.

Etiopathogenesis and clinical presentation of carotid body tumors.

The carotid body (CB) is a highly specialized small organ located at the bifurcation of the common carotid artery in the neck and plays an important role in acute adaptation to hypoxia. The most common diseased state of the carotid body is its enlargement (i.e., the CB paraganglioma), which can be caused by a genetic predisposition (hereditary paraganglioma, PGL) and by chronic hypoxic stimulation. The CB is the most common tumor site in head and neck paragangliomas. Currently, inactivating germline mutations in the mitochondrial complex II subunits SDHB, SDHC, and SDHD have been identified as genetic risk factors for CB tumors (CBTs). Another locus at chromosome 11q13, identified by linkage analysis in a single family, may harbor a fourth susceptibility gene. Although CBTs are mostly slow-growing and benign, they can cause significant morbidity because of their proximity to major arteries and nerves in the head and neck. Here, we review the etiological factors implicated in the development of CBTs and provide information pertaining to their clinical presentation. Although CBTs are rare, they have the potential to provide unique insights for tumorigenesis and oxygen sensing and signaling mechanisms.

Carotid body tumors: a review of 30 patients with 46 tumors.

Minimal morbidity occurs with resection of most carotid body tumors (CBT). With larger tumors significant injury to the cranial nerves has been reported. In order to assess the operative sequelae rate, 30 patients with CBT were reviewed. Sixteen patients either presented with bilateral carotid body tumors or had previously undergone a resection of the contralateral carotid body tumors, for a total carotid body tumor count of 46. Sixteen patients demonstrated a familial pattern while 14 were nonfamilial. Within the familial group, 14 of 16 presented with multiple paragangliomas as compared to 6 of 14 in the nonfamilial group. Tumor size ranged from 0.8 to 12 cm. Vascular replacement occurred in 2 of 20 patients with tumors < 5.0 cm, compared with 5 of 9 with tumors > 5.0 cm. Four patients lost cranial nerves with the resection: superior laryngeal nerve (SLN), 4; cranial nerve X, 1; cranial nerve XII, 1. Ten patients developed baroreceptor failure secondary to bilateral loss of carotid sinus function. First-bite pain occurred in 10 of 25 operative patients. Cranial nerve loss can be minimal with resection of carotid body tumors, however, baroreceptor failure and first-bite pain are postoperative sequelae that are often disregarded in the postoperative period.

Carotid body tumor: diagnostic and therapeutic approach.

Carotid body tumor may be clinically suspected when the only clues are physiologic manifestations of carotid body dysfunction or when a palpable cervical mass is evident upon presentation. In the latter case, the physiologic signs of carotid body dysfunction are usually recognizable. We have presented the case of a patient who was completely disabled by a slowly enlarging carotid body tumor. An attempt at surgical excision of the tumor was unsuccessful because of its proximity and adhesion to vital neck structures. An endocardial pacemaker inserted to ameliorate the episodes of bradycardia and hypotension accompanied by transient complete atrioventricular block resulted in only partial and temporary relief. Finally, irradiation of the tumor induced fast shrinkage and rapid regression of symptoms.

Cyanotic heart disease: "low altitude" risk for carotid body tumor?

A young woman with hypoplastic right heart syndrome developed a carotid body tumor at age 28. High altitude habitation is known to predispose to hyperplastic and neoplastic carotid bodies; emphysema and congenital cyanotic heart disease have recently been shown to induce hyperplasia of this oxytrophic tissue. Therefore, a link between congenital cyanosis and carotid body tumor is suggested by this patient. Carotid bodies are nonchromaffin paraganglionic analogues of the adrenal medulla. Congenital cyanosis has an association with pheochromocytoma. In the cyanotic milieu carotid body tumor may be a histological analogue of pheochromocytoma.

Chronic hypoxia and chemodectomas in bovines at high altitudes.

A severe degree of hyperplasia of the chief cells occurs in bovine carotid bodies at high altitudes, compared to sea level. As a result, the carotid body from an animal at high altitudes is significantly heavier and larger than the carotid body from an animal at sea level (P less than .001). In eight of 20 (40%) animals at high altitudes, the hyperplastic reaction had progressed to form chemodectomas. The findings suggest that neoplasia can result from chronic stimulation by a biologically essential environmental factor (atmospheric PO2) that acts pharmacologically on the target tissues (chief cells of the carotid body).