Carotid Body Paraganglioma Research Articles

Outcomes and Perioperative Complications of Surgical Resection on Canine Carotid Paragangliomas (21 Cases): A Veterinary Society of Surgical Oncology Study.

Carotid body paragangliomas represent an uncommon neoplasm in dogs. The objective of this study was to report outcomes and complications associated with surgical excision of carotid body paragangliomas in 21 dogs. Cases were recruited retrospectively via medical record review from 9 veterinary speciality centres. The perioperative complication rate was 52% (11/21). Complications encountered in this cohort related to removal of carotid body tumour included airway obstruction, aspiration pneumonia, megaesophagus, unilateral laryngeal paralysis, coughing and Horner's syndrome. The overall perioperative mortality rate was 4.7% (1/21 dogs) and median survival time was 554 days for the six patients with known dates of death. One- and two-year survival rates were 61% and 42%, respectively. This is the largest collection of carotid body paraganglioma cases reported in veterinary literature. Based on these results, surgical resection of carotid body paragangliomas was associated with low perioperative mortality and long survival times.

7068 Paraganglioma in Cyanotic Congenital Heart Disease

Abstract Disclosure: R. Lis: None. V. Hamidi: None. Paragangliomas arise from the non-chromaffin cells of the parasympathetic nervous system, which are composed of glomus cells. These function as chemoreceptors in response to hypoxia. Carotid body paragangliomas have been linked to conditions with chronic hypoxia. This was first seen in residents of high altitude locations in a case report presented by Saldana et. al and regression of a paraganglioma with resolution of hypoxia was reported by Gruber et. al. There have been few additional case reports of Paraganglioma in other hypoxic states. We present a rare case of a functional Paraganglioma in a patient with Cyanotic Congenital Heart Disease (CCHD).This is a 19 year old female with a history of CCHD due to double inlet left ventricle and transposition of the great arteries. Soon after birth, she had a fontan procedure. She subsequently developed fontan associated liver disease as well as chronic kidney disease, hypertension, sinus node dysfunction, and complete heart block. Her baseline oxygen saturation was 78-85%. Her heart rate was 40-49 beats per minute with upcoming plans for pacemaker placement. Her blood pressure ranged 90/50 to 150/80 mmHg on Amlodipine 5 mg and Lisinopril 2.5 mg. She routinely received abdominal imaging to monitor her liver disease. A liver MRI incidentally revealed a retroperitoneal mass concerning for a paraganglioma. Serum Normetanephrines were found to be 26.60 nmol/L (reference range less than 0.89). 24 hr Urine Norepinephrine was 1,187 ug/d (reference range 14-20). Further imaging was negative for additional sites of disease. Given her complete heart block, she was started on alpha blockade only prior to pacemaker placement. After the pacemaker was placed, she was started on beta blockade and underwent surgical resection of her paraganglioma. The pathology confirmed paraganglioma and mutation testing was negative for germline mutations including SDH, VHL, RET, NF1 mutations. Paragangliomas in patients with CCHD have been scarcely described in the literature given the rarity of both of these conditions. However, there is a relatively increased incidence of paragangliomas in the CCHD population due to chronic hypoxia triggering the hypoxia pathway. EPAS1 mutated HIF2alpha is often found to be the culprit in these patients. In addition, case reports have often described these patients to either be asymptomatic or have potential symptoms masked by their cardiac disease. Therefore, CCHD patients are at increased risk for paragangliomas and warrant additional awareness and regular screening. Screening has been proposed to start after 10 years of hypoxia in a case review by Agarwal et. al. as paraganglioma incidence in CCHD populations has not been seen before age 11. Incidence of recurrence is not yet widely studied, but significant concern for recurrence is warranted if the etiology of hypoxia is not reversed. Presentation: 6/3/2024

Endothelial cells and fibroblasts mediate the microenvironmental regulatory network of carotid body paraganglioma

Objective:To explore the gene expression characteristics of endothelial cells and fibroblasts in the microenvironment of SDHD-mutated carotid body tumors（SDHD-CBT）, to fine the functional enrichment of each subcluster, and to further explore the network of cell-cell interactions in the microenvironment of SDHD-CBT. Methods:The bioinformatics analysis was used to download and reanalyze the single-nuclear RNA sequencing data of SDHD-CBT, SDHB mutated thoracic and abdominal paraganglioma（SDHB-ATPGL）, SDHB-CBT, and normal adrenal medulla（NAM）, to clarify the information of cell populations of the samples. We focused on exploring the gene expression profiles of endothelial cells and fibroblasts subclusters, and performed functional enrichment analysis based on Gene Ontology（GO） resources. CellChat was used to compare the cell-cell interactions networks of different clinical samples and predict significant signaling pathways in SDHD-CBT. Results:A total of 7 cell populations were profiled. The main subtypes of endothelial cells in SDHD-CBT are arterial and venous endothelial cells, and the main subtypes of fibroblasts are myofibroblasts and pericytes. Compared to NAM, SDHB-CBT and SDHB-ATPGL, cell communication involving endothelial cells and fibroblasts in SDHD-CBT is more abundant, with significant enrichment in pathways such as FGF, PTN, WNT, PROS, PERIOSTIN, and TGFb. Conclusion:Endothelial cells and fibroblasts in SDHD-CBT are heterogeneous and involved in important cellular interactionprocesses, in which the discovery of FGF，PTN，WNT，PROS，PERIOSTIN and TGFb signals may play an important role in the regulation of microenvironment of SDHD-CBT.

Presentation of metastatic carotid body paraganglioma on F-18 FDG PET/CT: a rare disease

Carotid body paraganglioma is a slow growing tumor of head and neck region. It can rarely be malignant in nature which is characterized by distant metastases on anatomical imaging. We share an interesting presentation of a malignant carotid body on F-18 FDG PET/CT in form of liver and skeletal metastases.

The Role of Internal Carotid Artery Stent in the Management of Skull Base Paragangliomas.

Background: After two decades from its introduction in the lateral skull base paraganglioma surgery, the indications and results of preoperative internal carotid artery stenting should be critically assessed. Materials and Methods: Monocentric retrospective study on 26 patients affected by head and neck paragangliomas (19 tympanojugular paragangliomas, 4 carotid body paragangliomas, 3 vagal paragangliomas) preoperatively treated with internal carotid artery stents between 2008 and 2023. The preoperative findings, the intraoperative complications and the final surgical results were analyzed. Results: The stent complication rate was less than 3.1%. Self-expanding highly flexible intracranial nitinol stents were applied. In all cases, it was possible to completely mobilize the internal carotid artery and perform a vascular dissection of the tumor. Gross total tumor resection was possible in 85% of cases. The median follow up was 7.83 y (SD +/- 3.93 y). No local recurrence was observed. Conclusions: The preoperative vascular stent facilitates tumor dissection from the internal carotid artery without risk of vascular damage, helping the surgeon to achieve surgical radicality. The vascular stent is indicated in the case of revision surgeries, circumferential involvement of the vessel and in cases with non-insufficient intracerebral crossflow. Procedural complications, temporary antiplatelet therapy and delay of surgery are the limitations of the procedure.

Resection of Secreting Right Carotid Body Paraganglioma: 2-Dimensional Operative Video

Secreting carotid body paragangliomas are very rare entities that account for less than 1% of all tumors of the head and neck region. 1-3 These vascular lesions splay the internal and external carotid arteries as they enlarge and cause increased catecholamine production in affected individuals. Surgical resection is definitive treatment, but preoperative embolization of the tumor can decrease its vascular supply and aid in surgery. Patients undergoing treatment require preoperative administration of alpha and beta adrenergic blockade to avoid intraoperative and postoperative complications. In this case, a 49-year-old woman presented with a growing neck mass compatible with a carotid body tumor. Preoperative MRI demonstrated a lesion splaying the external and internal carotid arteries. Angiogram demonstrated a vascular tumor, which was embolized before surgery. The patient consented to the procedure and the publication of her case and images. The University of Utah does not require Institutional Review Board approval for the presentation of a single case. This step-by-step video illustrates the surgical resection of her secreting right carotid body paraganglioma. Skull base neurosurgeons must understand the anatomy of vessels and nerves of the neck to safely and successfully resect such tumors.

Carotid body tumors: a review

Carotid body tumor or paraganglioma, is located periadventitially in relation to the carotid bifurcation. Generally, the blood supply of carotid tumors is abundant, it comes mainly from the branches of the external carotid arteries, although cases have been reported where the irrigation comes from the internal carotid artery, vertebral artery, ascending pharyngeal artery and superior thyroid. Although its etiology is unknown, different factors have been associated that contribute to its incidence, such as genetic factors and states of chronic hypoxia. Histologically, they are well vascularized tumors. Between the capillaries there are groups of tumor cells known as Zellballen's pseudoalveolar pattern. These are cells with eosinophilic granular cytoplasm and small round or oval nuclei. The tumor is mobile, but with limitation to mobilization in the cephalocaudal direction. The mass can transmit the carotid pulse due to its proximity to the carotid, and it may also be accompanied by a murmur or thrill. Usually the carotid glomus is identified by clinical examination, so consideration of multiple differential diagnoses. The treatment of choice is surgical excision. The need for preoperative embolization is controversial. Embolization before surgery is recommended to improve surgical success with reduced blood loss as well as reduce the risk of cranial nerve injury. The decision to perform presurgical embolization or not depends on the surgeon.

Clinical outcomes and challenges of surgical extirpation for carotid body paraganglioma in South Korea: a single-center retrospective study

BackgroundCarotid body paraganglioma (CBP) is a rare, highly vascularized, and slow-growing neuroendocrine tumor. Surgical resection is the definitive treatment for CBP, however, it remains challenging due to the tumor’s proximity to critical blood vessels and cervical cranial nerves. This study aimed to document the characteristics of CBP and examine the clinical outcomes of patients following surgical extirpation of CBP.MethodsThis is a single-center retrospective review analyzed patients who underwent CBP extirpation. We examined the patient demographics, preoperative clinical features, tumor characteristics, levels of catecholamines and their metabolites in the serum and urine. Surgeries were performed by one vascular surgeon with follow-ups at 1,3,6 months and yearly thereafter. Logistic regression analysis was conducted to identify risk factors associated with the occurrence of either permanent or temporary cervival cranial nerve palsy (CNP).ResultsFrom September 2020 to February 2023, this study examined 21 cases of CBP removal surgeries that were carried out in 19 patients. The mean age of the patients was 38.9 ± 10.9 years and the percentage of males was 57.1% (n = 12). The most common preoperative clinical feature was painless neck mass (n = 12; 57.1%). Complete resection was achieved in 20 cases; excluding one case with pathologically proven sclerosing paraganglioma. Vascular procedures were performed in four cases (ECA resection, n = 2; primary repair of ICA tear without carotid shunting, n = 1; and ICA patch angioplasty with carotid shunting, n = 1). Temporary cranial neurologic complications, specifically aspiration and hoarseness occurred in four (19.0%), and three (14.3%) cases, respectively. Hoarseness associated with permanent CNP persisted for more than 6 months in two cases (9.5%). No recurrence or mortality was observed during the follow-up period.ConclusionsSurgical resection is the primay treatment approach for CBP; however, it poses risks of vascular or cervical CNP. The intraoperative estimated blood loss was the only identified risk factor for CNP.

Paraneoplastic Limbic Encephalitis From a Carotid Body Paraganglioma Presenting as Persistent and Worsening Confusion

Background: Paraneoplastic Syndromes (PNS) are rare conditions in which patients experience a variety of symptoms from altered immune systems due to underlying malignancy. Paraneoplastic Limbic Encephalitis (PLE) is a subtype of PNS in which autoantibodies to cancer cells cross-react with cells in the central nervous system, particularly in the medial temporal lobe. Here we present a 38-year-old, previously normal male who presented with persistent and worsening confusion and was diagnosed with a very rare PLE secondary to a carotid body paraganglioma. Case: A 38-year-old male with medical history of hypertension and polysubstance abuse was admitted initially for confusion, arm weakness, and memory loss. He denied having headache, fever, chills, or neck stiffness. Further history obtained from family revealed he was previously cognitively intact. Imaging was consistent with carotid body paraganglioma and limbic encephalitis. A 5-day course of high dose steroids and plasmapheresis was initiated. Plasmapheresis was performed every other day for 5 treatments with marked improvement in mental and renal function at the time of the third treatment. Biopsies obtained were consistent with carotid body paraganglioma and surrounding lymphadenopathy was negative for disease. Embolization was performed with subsequent excision of the tumor and eventual resolution of symptoms. Conclusion: This is to our knowledge the first documented case of paraneoplastic limbic encephalitis associated with a carotid body paraganglioma. Our patient had improved following resection of the underlying paraganglioma and experienced short-term improvement with high-dose steroids and plasmapheresi

Ectopic thyroid tissue presenting as a carotid body paraganglioma

Ectopic thyroid tissue is a rare developmental abnormality, typically presenting with midline ectopia due to incomplete embryological migration via the thyroglossal duct. The presence of ectopic thyroid tissue lateral to the midline is very rare, accounting for 1–3% of all ectopic thyroid tissue. Clinically, these lesions are often mistaken for other diagnoses including enlarged lymph nodes or metastatic tumours. We present a case of lateral ectopic thyroid tissue presenting as a presumed carotid body paraganglioma in a middle-aged woman. The patient presented with a slow-growing lateral neck mass which was clinically and radiologically consistent with a carotid body paraganglioma. She subsequently underwent tumour excision after which histological analysis identified ectopic thyroid tissue with no evidence of malignancy.

Risks to predict blood loss and cranial nerve injury in carotid body paraganglioma resection

Objective: To investigate clinical and imaging parameters to predict blood loss and cranial nerve injury (CNI) following carotid body paraganglioma (CBP) resection. Methods: A retrospective examination of clinical and imaging data was conducted on 63 patients who underwent CBP resection at Xiangya Hospital of Central South University from January 2016 to December 2022, including 23 males and 40 females, aged 26-87 years old. Three imaging parameters including tumor volume, the angle of contact with the internal carotid artery (ICA), and the distance to the base of skull (DTBOS) were gauged using the IMEDPACS software on CTA and MR imaging. The predictive efficacies of age, gender, Shamblin classification, and three imaging parameters for blood loss and CNI following surgery were analysed. Logistic composite parameter models were constructed and their predictive validity was assessed. Results: Multivariate logistic regression analysis underscored that only tumor volume (OR=1.381,95%CI:1.167-1.507,P=0.001) showed significant statistical correlations with blood loss following surgery. Area under curve (AUC) values of 0.910 for receiver operating characteristic (ROC) curves showed a sensitivity of 1.000 and a specificity of 0.694. Tumor volume (OR=1.126,95%CI:1.030-1.231, P=0.002) and DTBOS (OR=0.225,95%CI:0.081-0.630,P=0.005) were significantly associated with postoperative CNI. The analysis of logistic composite model showed AUC values for tumor volume, DTBOS and combination of the two parameters were 0.858, 0.788, and 0.872, respectively. The model for combination of tumor volume and DTBOS also proved superior in predicting postoperative CNI (Z=3.106, P<0.001), with a sensitivity of 0.833 and a specificity of 0.769. Conclusions: Tumor volume and DTBOS emerged as effective predictors for blood loss and/or CNI in patients with CBP resection. Moreover, the logistic composite parameter model outclassed single-parameter models in terms of their predictive clinical value.

Pathophysiological features of neuroendocrine tumors in cyanotic congenital heart disease: a systematic review

Abstract Background Patients with cyanotic congenital heart disease (CCHD) have an increased risk to develop pheochromocytomas or paragangliomas (PPGL), which are rare neuroendocrine tumours molecularly driven by the activation of the hypoxia-inducible factor 2-alpha (HIF-2α ). Purpose To define the clinical characteristics of CCHD-PPGL patients. Methods An international multicentre CCHD-PPGL consortium from 8 countries was stablished. The group performed a systematic review of clinic-pathological features of 149 CCHD-PPGL cases and compared to 1559 CCHD non-PPGL patients. Results CCHD-PPGL were predominantly women (56.4%) with univentricular heart (UVH) (55.0%), followed by tetralogy of Fallot (23.5%). Most patients remained unoperated (28.6%) or had only undergone a palliative procedure (25.8%), and the mean saturation at diagnosis was 84.0%. The median age at PPGL diagnosis was 27.0 yo [20-38]. Pheochromocytoma (PCC) occurred in 36.9% of patients, abdominal or thoracic paraganglioma (TA-PGL) in 40.3%, carotid body paraganglioma (CB-PGL) in 14.7% and a combination in 8.0%. Most CB-PGLs were non-secreting, non-symptomatic tumors while PCC and TA-PGL were mostly noradrenalin-secreting and symptomatic tumors. Metastatic disease was documented in 10.3% of non-CB and none in CB-PGL . Comparing to patients with PCC or TA-PGL, CB-PGL patients were predominantly female (81.8% vs 52.0%), older at time of diagnosis (43 yo [36.0 – 52.0] vs 25.0 yo [19.0-35.0], p&amp;lt;0.01) and with a longer period of cyanosis at diagnosis (37.0 [23-47] vs 23.0 [13-46], p&amp;lt;0.01). Patients with Fontan procedure were mostly men (63.3%) who developed a noradrenalin-secreting PCC or a TA-PGL (42.0% and 58.0% respectively) at an earlier age than non-Fontan patients (22.0yo [18.0-27.0] vs 29.0yo [21.0-41.0], p&amp;lt;0.01). Patients with Eisenmenger physiology were female patients (100%) who developed mostly CB-PGL, non-secreting tumors (54.5%) and were older at diagnosis (48.0 yo [42-58]). Compared to a cohort of 1599 CCHD non- PPGL patients, CCHD-PPGL were predominantly women (57.7% vs 44.8%, p&amp;lt;0.01), with forms of UVH (53.7% in CCHD-PPGL vs 14.1% in CCHD, p &amp;lt;0.01 ) and were mainly unoperated and palliated patients (27.1% and 26.4% respectively vs 10.0% and 5.3% in CCHD, p &amp;lt;0.01). CCHD-PPGL patients showed lower levels of oxygen saturation (80.0% [76.0-85.0] vs 84.0% [80.0-88.0], p&amp;lt;0.01) and higher haematocrit levels (60.0% [52.0-66.5] vs 53.3% [46.3-62.0], p&amp;lt;0.01) than CCHD without PPGL. Conclusions Patients with CCHD and lifelong cyanosis, and especially those with Eisenmenger physiology, probably develop CB-PGL as an adaptive response to chronic systemic hypoxemia, present a good clinical course, and usually do not require an initial surgical approach. In patients with Fontan circulation, the risk of developing a sympathetic thoracic-abdominal PPGL persists, despite correction of hypoxemia, possibly due to the initial hypoxemia during adrenal medulla post-natal development.

SAT487 A Case of Mistaken Identity: A Rare Presentation of Ectopic Thyroid Tissue

Abstract Disclosure: N. Doshi: None. R. Azimzade: None. A. Rajpal: None. Background: Ectopic thyroid tissue (ETT) lateral to the midline is very rare, and its presence at the carotid bifurcation is exceedingly unique. Paraganglioma is the most common primary tumor at the carotid bifurcation, often called a carotid body tumor. We hereby present a case of lateral ETT with radiological features similar to paraganglioma. Case Description: A 72-year-old female with history of GERD was referred to us for evaluation of a well-circumscribed, slightly tender left neck mass. She has had the mass for approximately 15 years with previous evaluation with ultrasound in Yemen, where she was told to undergo surgery to remove it. She did not pursue surgery at that time. She moved to the U.S. one year ago and was re-evaluated for the neck mass. On examination, a firm mass was noted on the left side of the neck, followed by an ultrasound which demonstrated a 4.5 cm mass at the left carotid bifurcation and an enlarged right thyroid lobe of the same echogenicity with no tissue in the left thyroid bed. She had no clinical symptoms suggesting of hypo or hyperthyroidism. Laboratory examination showed suppressed TSH with elevated T3 suggesting thyrotoxicosis. CT neck was obtained for further characterization of the left neck mass which showed a hyper-enhancing, lobular soft tissue mass at the carotid bifurcation extending from the mandible to the level of the thyroid isthmus, concerning for carotid body paraganglioma or schwannoma. An I-123 scan demonstrated 24% (increased) uptake in the right thyroid lobe and minimal uptake in the carotid bifurcation tissue. The patient is currently being treated medically for thyrotoxicosis. Based on its ultrasonographic appearance, mild uptake on the I-123 scan, and no clinical suggestion of paraganglioma, the left neck mass is presumed to be ETT and no surgical intervention is being pursued. It is possible that the right lobe is thyrotoxic, suppressing iodine uptake in the ectopic tissue. Conclusion: This case demonstrates a unique presentation of ETT in the left carotid bifurcation with a thyrotoxic right lobe. It is difficult to distinguish the precise composition of neck masses at the carotid bifurcation, which has important implications for management. Often, an official diagnosis of thyroid tissue is made with histopathology only after the mass is surgically excised. Most ETT is benign in nature, and many times it is the only thyroid tissue available, thus surgery is not indicated. It is especially difficult to distinguish between ETT and paraganglioma on imaging itself. Somatostatin receptor scintigraphy, Ga-68/PET scanning, or iodine uptake scan can be useful to distinguish ETT from paraganglioma. Despite its rarity, lateral ETT must be included in the differential diagnosis of carotid body paraganglioma. Presentation Date: Saturday, June 17, 2023

Preoperative percutaneous Onyx embolization of carotid body paragangliomas with balloon test occlusion.

The study aims to analyze our first experience with direct percutaneous embolization of carotid body tumors (CBTs) using ethylene-vinyl alcohol copolymer (Onyx) along with balloon test occlusion (BTO). A retrospective preliminary single-center study was conducted at the Otorhinolaryngology and Head and Neck Surgery Department and the Medical Imaging Department of the University Teaching Hospital. A consecutive series of three patients with CBTs was treated at the local institution between October 2018 and June 2019. All three patients underwent preoperative percutaneous embolization using ethylene-vinyl alcohol copolymer (Onyx 18) with the addition of BTO. Outcome measures were the percentage of tumor devascularization, intraoperative blood losses, and operation times. BTO was evaluated by clinical neurological examination and neurosonological transcranial Doppler examination of the middle cerebral artery (MCA). Devascularization of all three tumors was complete or near complete. All three tumors were surgically extirpated with excellent surgical outcomes. The blood losses were minimal, and the average operation time was 2 h and 8 min. BTO was positive in one patient, which was valuable additional information on carotid branches ligation limitations. The other two patients showed negative BTOs with the result of safety of eventual carotid arteries ligations. Preoperative direct percutaneous embolization of CBT with Onyx is a highly effective procedure that significantly facilitates surgery. BTO provides valuable additional information on the most appropriate and safe surgical approach.

SDH deficiency is very common in carotid body paragangliomas: Genetic counseling and testing should be offered to all patients.

Collectively, germline pathogenic variants in succinate dehydrogenase (SDH) genes are the most common cause of hereditary paragangliomas. Loss of immunohistochemical expression of SDHB protein (termed SDH deficiency) occurs whenever there is biallelic inactivation of any SDH gene. We sought to estimate the prevalence of SDH deficiency in patients with carotid body paragangliomas. We identified all carotid body paragangliomas that had undergone surgical excision at our institution over the last 30 years. If SDHB immunohistochemistry was not performed at the time of excision, it was performed on archived material. There were 64 carotid body paragangliomas identified in the 62 patients. Two-thirds of the patients were female, and 43 (67%) were SDH-deficient. Up to two-thirds of all carotid body paragangliomas are associated with SDH deficiency. Therefore, genetic testing and counseling should be offered to all patients with carotid body paragangliomas, regardless of age or family history.

Carotid body paraganglioma metastatic to spine causing cord compression: a case report

BackgroundCarotid body tumors (CBTs) are rare neuroendocrine neoplasms arising near the carotid bifurcation with a reported incidence of 1 to 2 cases in 100,000 patients. Most CBTs are sporadic, benign, slow-growing, and non-secreting, but untreated CBTs can grow locally to compress the nearby blood vessels, esophagus, and airway. Regional metastases can occur in 5% to 10% of cases, but distant metastases are exceedingly rare, occurring in roughly 1–2% of cases. As such, the optimal treatment for metastatic CBTs is not well-defined. We report a rare case of a patient with CBT distant metastases causing spinal cord compression.Case presentationA 40-year-old African American female presented with a right neck mass, headaches, vertigo, tinnitus, hoarseness, and dysphagia. Imaging demonstrated a Shamblin II right neck mass; subsequent transcervical resection and pathology showed a carotid body paraganglioma. The patient recurred locally near the carotid bifurcation, so she underwent Stereotactic Body Radiation Therapy to the recurrent right neck disease. She later re-presented with new onset bilateral lower extremity weakness, dysmetria, and numbness. She was found to have metastatic disease to the thoracic spine causing spinal cord compression. She underwent laminectomy, tumor resection, and posterior fixation followed by adjuvant radiation therapy. She was started on systemic therapy with sunitinib. She eventually progressed with metastatic disease to the right iliac bone, which was treated with palliative radiotherapy. Second line systemic therapy with capecitabine and temozolomide was started. At last follow up, the patient was asymptomatic with stable persistent disease.ConclusionsParagangliomas often exhibit a prolonged interval to the development of progression; locoregional recurrences or rare distant metastases have been reported to occur as many as 20 years from diagnosis. The natural course of CBTs in other cases as well as the present case call into question the idea that CBTs are truly benign; instead CBTs may be indolent tumors with metastatic potential. Treatment choices for CBTs include surgical resection, radiation therapy, and systemic therapy, though the optimal treatment regimen for metastatic CBTs is not well-defined. A more advanced understanding of CBT pathophysiology, disease classification, risk stratification, and treatment options is needed to improve outcomes for patients.

BILATERAL CAROTID BODY PARAGANGLIOMAS - LITERATURE REVIEW AND COMMENTS IN A PATIENT WITH NO SIGNS OF MEN SYNDROME.

To present the most important features of carotid body paragangliomas, illustrating the clinical characteristics, associated with a thorough analysis of the diagnostic imaging elements, but also the current therapeutic strategies, with respective anatomical, surgical considerations and potential complications that can occur. Surgical resection is the main line of treatment. The complex anatomy of the cervical region and the close relationships of carotid body paragangliomas with carotid vessels and cranial nerves, as well as its intense vascularization makes the surgical intervention a real challenge even for an experienced surgeon. Starts from a bilateral carotid paraganglioma in a 35-year-old male, with painless lateral neck swelling, accidentally discovered by his barber about two years ago. Diagnosis was suspected on the basis of history, clinical and radiological findings. "Wait and scan" strategy plus endocrinologic assessment for MEN syndromes were considered the optimal therapeutic approach in this case.

Bilateral Carotid Paraganglioma: Case Report; Successful Surgical Excision, Radiological Image and Review of the Literature

Introduction: Carotid body tumors are rare neoplasms that generally present as asymptomatic slow-growing masses in the neck, commonly called cervical paragangliomas, highly vascularized whose cells originate from the embryonic neural crest, carotid glomus tumor is uncommon, representing 1 out of every 30,000 head and neck tumors, they are located in the adventitia of the vessels, they usually grow surrounding the arteries of the carotid bifurcation and the nerves that surround it, in Ecuador the prevalence is at 55 years of age with greater frequency in women [1]. Clinical Case: A 33-year-old female patient with no significant clinical history, presented with a painful hard mass in the right cervical region that progressively increased in size, for the past 6 months. On physical examination, a tumor in the right cervical region of approximately 5 centimeters in diameter was found, with a hard consistency attached to deep planes, for which Eco Doppler and AngioTac of the neck were performed, which reported bilateral carotid paraganglioma. Excision of the glomus was necessary due to its size right carotid artery, surgery using a right cervico-lateral approach, identifying the vascular tumor mass of 4.8 x 2.9 x 2.8 cm in diameter, which was located in the carotid bifurcation. Removal of Shamblin II right carotid body paraganglioma by temporary clamping of the common carotid artery and the digital dissection method, there was no intraoperative massive bleeding or cranial nerve deficits in the postoperative period with favorable evolution, surgical wound in good condition during follow-up in outpatient consultation. Conclusion: Glomus carotid tumors are generally benign and diagnosed late. Imaging studies are essential for its diagnosis and staging.

Preoperative Balloon Occlusion Test of the Carotid Artery and Preoperative Tumor Embolization on Paraganglioma of Carotid Body: 20-Year Experience in a Single Institute and Literature Review

Background and Objectives Carotid body paraganglioma is the common type of carotid body tumor for which angiography, carotid artery balloon occlusion test (BOT) and tumor embolization could be considered before the surgery. We analyzed cases in a single institute and reviewed related literature to investigate the necessity of these preoperative examinations.Subjects and Method Medical records of patients who were diagnosed with paraganglioma were retrospectively analyzed from 2000 to 2019.Results Sixteen patients were identified. Of the total, 14 patients underwent surgery at this institute, and 13 underwent angiography. Of the 13 patients who underwent angiography, 6 patients underwent carotid artery BOT, and 12 patients underwent tumor embolization. The average tumor size of 6 patients who underwent carotid artery BOT was 28.7 mm, and 8 patients who did not undergo carotid artery BOT was 30.1 mm. The average tumor size of 12 patients who underwent tumor embolization was 29.4 mm. Two patients did not undergo tumor embolization, and their average tumor size was 30 mm. In 1 patient, both preoperative angiography and carotid artery BOT were performed, but tumor embolization was not performed due to spasm of tumor vessels.Conclusion Preoperative carotid artery BOT can be performed to reduce side effects in patients with the potential for carotid resection. In addition, tumor embolization is performed regardless of tumor size. By reducing the amount of bleeding during surgery and reducing the size of the tumor, it is possible to secure an appropriate surgical field of view to facilitate operation during surgery; however, its effectiveness needs to be clearly identified.

Multiparametric analysis of carotid body tumours: a pictorial essay.

Carotid body tumours (CBT), also called carotid body paraganglioma, are highly vascular and histologically portray paraganglion cells. They are typically found at the carotid bifurcation and result in the splaying of the internal and external carotid arteries (ICA and ECA). Recent literature supports the role of chronic hypoxia in the etiology of CBT. This pictorial essay discusses how CBT is an uncommon etiology for common clinical problems such as transient ischemic attacks. It also discusses imaging techniques to precisely map out the tumour for surgical resection using advanced imaging modalities and techniques.