Imaging and management of head and neck paragangliomas

Perioperative evaluation and follow-up analysis of carotid body tumor by Color Doppler Ultrasound

OBJECTIVES

The value of Color Doppler Ultrasound (CDU) for perioperative evaluation and follow-up outcomes of carotid body tumor (CBT) remains elusive. This study aimed to investigate the role of CDU in CBT in our center.

METHODS

From January 2015 to December 2020, 75 patients with CBT were included in the study. Computed Tomography Angiography (CTA) and CDU data of patients were collected and analyzed. The postoperative recovery and follow-up outcomes were summarized.

RESULTS

A total of 91 CBTs in 75 patients were included in the study. 73.3% of patients had unilateral lesions, while 26.7% had bilateral lesions. Lesions were categorized as Shamblin I (4.4%), Shamblin II (52.7%), and Shamblin III (42.9%). 79.5% lesions were treated by surgical resection, 12.3% were treated by surgical resection with internal carotid artery reconstructed by artificial vessel, while 8.2% were treated by surgical resection with internal carotid artery reconstructed by autogenous great saphenous vein. Compared with CTA, the sensitivity of CDU for detection of CBT was 96.7%, the sensitivity and specificity of CDU for detection of Shamblin Ⅰ lesions were both 100%, the sensitivity and specificity for Shamblin Ⅱ were 100% and 72.1%, respectively, while the sensitivity and specificity for Shamblin Ⅲ were 69.2% and 100%, respectively. There were no statistically significant differences between CTA and CDU for detection of the maximal diameter, volume of CBT and distance between the end of the tumor and the mastoid process. 79.7% of patients were followed up with CDU. Recurrence of CBT occurred in 1 patient. CDU showed that stenosis and occlusion of artificial vessel occurred in 1 and 6 patients, respectively. Occlusion of autogenous great saphenous vein was found in 2 cases.

CONCLUSIONS

CDU can accurately diagnose Shamblin Ⅰ CBT, have high sensitivity for Shamblin Ⅱ and high specificity for Shamblin Ⅲ CBT. It plays an important role in diagnosis, perioperative evaluation and follow-up analysis of CBT.

Imaging of Pheochromocytomas and Paragangliomas

Pheochromocytomas/paragangliomas are unique in their highly variable molecular landscape driven by genetic alterations, either germline or somatic. These mutations translate into different clusters with distinct tumor locations, biochemical/metabolomic features, tumor cell characteristics (eg, receptors, transporters), and disease course. Such tumor heterogeneity calls for different imaging strategies in order to provide proper diagnosis and follow-up. This also warrants selection of the most appropriate and locally available imaging modalities tailored to an individual patient based on consideration of many relevant factors including age, (anticipated) tumor location(s), size, and multifocality, underlying genotype, biochemical phenotype, chance of metastases, as well as the patient's personal preference and treatment goals. Anatomical imaging using computed tomography and magnetic resonance imaging and functional imaging using positron emission tomography and single photon emission computed tomography are currently a cornerstone in the evaluation of patients with pheochromocytomas/paragangliomas. In modern nuclear medicine practice, a multitude of radionuclides with relevance to diagnostic work-up and treatment planning (theranostics) is available, including radiolabeled metaiodobenzylguanidine, fluorodeoxyglucose, fluorodihydroxyphenylalanine, and somatostatin analogues. This review amalgamates up-to-date imaging guidelines, expert opinions, and recent discoveries. Based on the rich toolbox for anatomical and functional imaging that is currently available, we aim to define a customized approach in patients with (suspected) pheochromocytomas/paragangliomas from a practical clinical perspective. We provide imaging algorithms for different starting points for initial diagnostic work-up and course of the disease, including adrenal incidentaloma, established biochemical diagnosis, postsurgical follow-up, tumor screening in pathogenic variant carriers, staging and restaging of metastatic disease, theranostics, and response monitoring.

A Rare Differential of Epistaxis

Glomus tympanicum is a type of glomus tumor that affects the middle ear, located at the auricular branch of the vagus nerve. Glomus tumors, in general, are rare, slow-growing tumors and may not require surgery in some patients. It can be challenging to manage due to its hypervascularity, location, and advanced stage of diagnosis. Although glomus tympanicum commonly presents with pulsatile tinnitus and conductive hearing loss, it presented in our patient with large-volume hemoptysis and epistaxis, requiring urgent diagnostic and therapeutic interventions. We highlight the unique presentation of a 48-year-old female with sudden onset large-volume hemoptysis and epistaxis, leading to the discovery of a hypervascular glomus tympanicum in the right middle ear, identified via MRI. On arrival, her vitals were within normal limits, and a physical examination was pertinent for the obvious ongoing bleeding from her mouth. The examination revealed increased respiratory effort and bilateral crackles. Laboratory values were pertinent for hemoglobin of 11.8 g/dl. Ear examination revealed a large, vascular-appearing mass filling the right ear. An MRI of the face and neck showed an avidly enhancing 3.7 cm x 1.8 cm x 1.2 cm mass within the right middle ear and mastoid cavity, extending into the external auditory canal and through the eustachian tube into the nasopharynx. The mass was inseparable from the lateral border of the internal auditory canal in the petrous canal. Due to concern for glomus tympanicum, the patient underwent urgent embolization and subsequent tumor resection. Considering our patient initially presented large-volume hemoptysis, there was concern for alveolar hemorrhage. However, as she had no increased oxygen requirement, there was suspicion of massive epistaxis mistaken for hemoptysis. Due to large volume epistaxis, she underwent urgent embolization as resection could have been challenging due to increased vascularity. It is important to remember that massive epistaxis may not present with blood in the anterior nares, thereby delaying diagnosis and management. Furthermore, probing such tumors should be avoided as it may lead to life-threatening bleeding.

Microsurgery in carotid body paraganglioma

Objectives

In carotid paraganglioma surgery, magnification is crucial to properly evaluate the anatomical relationships between mass, carotid wall, cranial nerves, tumour vascular supply and fascial envelope. The aims of this study are to describe the microsurgical technique, along with the underlying microsurgical anatomy, and to assess outcomes in terms of disease control, complications and functional results.

Methods

Twenty-six patients, accounting for 29 carotid paragangliomas, treated with microsurgery by the same senior surgeon over a 35-year period, were included.

Results

No carotid injury requiring repair, nor peri- or post-operative stroke occurred in this series. No surgical injury of the main trunk of VII to XII cranial nerves occurred. Complete excision was obtained in all cases and no recurrence was observed during follow-up.

Conclusions

The small study size and its retrospective nature suggests caution; however, our results show that microsurgery can allow a safe and precise dissection of the carotids and nerves.

Hypoxic Signaling Pathways in Carotid Body Tumors

Carotid body tumors (CBTs) are rare tumors with a 1-2 incidence per 100,000 individuals. CBTs may initially present without apparent symptoms, and symptoms begin to arise since tumors grow bigger to compress surrounding tissue, such as recurrent laryngeal nerve and esophagus. Also, the etiology of CBTs remains unclear since it is more likely to occur in those who live in high-altitude areas or suffer from chronic hypoxic diseases such as COPD. SDH mutations and familial inheritance have been reported to be related to CBTs. SDH complexes play crucial roles in aerobic respiration, and SDH mutations in CBTs have been reported to be associated with hypoxia. Hypoxic signaling pathways, specifically hypoxic markers, have attracted more research attention in tumor exploration. However, the existing literature on these signaling and markers lacks a systematic review. Also, therapeutic approaches in CBTs based on hypoxic signaling are rarely used in clinics. In this review, we concluded the role of hypoxic signaling and markers and their potential implications in the initiation and progression of CBTs. Our findings underscore the involvement of the SDH family, the HIF family, VEGFs, and inflammatory cytokines (ICs) in tumorigenesis and treatment. Of particular interest is the role played by SDHx, which has recently been linked to oxygen sensing through mutations leading to hereditary CBTs. Among the SDH family, SDHB and SDHD exhibit remarkable characteristics associated with metastasis and multiple tumors. Besides SDH mutations in CBTs, the HIF family also plays crucial roles in CBTs via hypoxic signaling pathways. The HIF family regulates angiogenesis during mammalian development and tumor growth by gene expression in CBTs. HIF1α could induce the transcription of pyruvate dehydrogenase kinase 1 (PDK1) to inhibit pyruvate dehydrogenase kinase (PDH) by inhibiting the TCA cycle. Then, carotid body cells begin to hyperplasia and hypertrophy. At the same time, EPAS1 mutation, an activating mutation, could decrease the degradation of HIF2α and result in Pacak-Zhuang syndrome, which could result in paraganglioma. HIFs can also activate VEGF expression, and VEGFs act on Flk-1 to control the hyperplasia of type I cells and promote neovascularization. ICs also play a pivotal signaling role within the CB, as their expression is induced under hypoxic conditions to stimulate CB hyperplasia, ultimately leading to CBTs detecting hypoxic areas in tumors, and improving the hypoxic condition could enhance photon radiotherapy efficacy. Moreover, this review offers valuable insights for future research directions on understanding the relationship between hypoxic signaling pathways and CBTs.

[Simultaneous occurrence of facial neurinoma in internal auditory canal and middle ear paraganglioma in patient. Unusual combination and difficult surgical task]

CLINICAL CASE

The 59-year-old patient complained of hearing loss on the left, ear murmur for a long time, periodic pain and discomfort in the left ear, dizziness for 6 months. She was found to have concurrent vestibular schwannoma in the internal auditory canal and temporal bone paraganglioma. Both tumors were removed in one operation. The schwannoma was removed by translabirinth access due to preoperative deafness, while the glomus tumor was removed during this access. Postoperative biopsy showed the presence of two unrelated diseases: paraganglioma (ICD-0 code 8690/3) and schwannoma (ICD-0 code 9560/0).

Co-existing Paraganglioma, Cholesteatoma, and Otomastoiditis With Overlapping Imaging Features: A Diagnostic Challenge

Head and neck paragangliomas are rare neuroendocrine tumors arising from the autonomic nervous system. Imaging hallmarks of paragangliomas of the head and neck include an enhancing soft-tissue mass in the carotid space, jugular foramen, or tympanic cavity on computed tomography; a salt-and-pepper appearance on standard spin-echo magnetic resonance imaging; and an intense blush on angiography. Imaging studies depict the location and extent of tumor involvement, help determine the surgical approach, and predict operative morbidity and mortality. However, an atypical presentation of paragangliomas, especially when co-existing with other middle ear pathologies that have overlapping imaging findings, can often be misleading. Here, we report a case of simultaneous occurrence of paraganglioma, cholesteatoma, and otomastoiditis in a young adult female.

Retrospective analysis of carotid body tumor surgical management: roles of preoperative image investigation and preoperative embolization

OBJECTIVE

To analyze the management of carotid body tumors (CBTs), particularly the use of preoperative embolization (EMB) and image features in minimizing surgical complications.

BACKGROUND

CBT surgery is a challenging procedure, and the role of EMB in CBT surgery has remained unclear.

METHODS

A total of 200 CBTs were identified among 184 medical records involving CBT surgery. Regression analysis was used to explore the prognostic predictors of cranial nerve deficit (CND), including image features. In addition, blood loss, operation times, and complication rates were compared between patients who had surgery only versus patients who had surgery along with preoperative EMB.

RESULTS

Overall, 96 males and 88 females were identified for inclusion in the study, with a median age of 37.0 years. Computed tomography angiography (CTA) showed the presence of a tiny gap adjacent to the encasement of carotid vessels, which could help minimize carotid arterial injury. High-lying tumors that encased the cranial nerve were usually managed with synchronous cranial nerve resection. Regression analysis revealed that the incidence of CND was positively associated with Shamblin Ⅲ, high-lying, and a maximal CBT diameter of ≥ 5cm. Among 146 EMB cases, two cases of intracranial arterial embolization occurred. No statistical difference was found between the EBM and Non-EBM groups in terms of bleeding volume, operation time, blood loss, blood transfusion requirement, stroke, and permanent CND. Subgroup analysis revealed that EMB decreased CND in Shamblin III and low-lying tumors.

CONCLUSIONS

CBT surgery should be performed with preoperative CTA to identify favorable factors for minimizing surgical complications. Shamblin Ⅲ or high-lying tumors, as well as CBT diameter, are predictors of permanent CND. EBM does not reduce blood loss or shorten operation time.

Association of Tumor Volumetry with Postoperative Outcomes for Cervical Paraganglioma

Objectives: To analyze the association of tumor volume with outcome after surgery for cervical paraganglioma. Materials and Methods: This retrospective study included consecutive patients undergoing surgery for cervical paraganglioma from 2009-2020. Outcomes were 30-day morbidity, mortality, cranial nerve injury, and stroke. Preoperative CT/MRI was used for tumor volumetry. An association between the volume and the outcomes was explored in univariate and multivariable analyses. A receiver operating characteristic (ROC) curve was plotted, and the area under the curve (AUC) was calculated. The study was conducted and reported according to the STROBE statement. Results: Volumetry was successful in 37/47 (78.8%) of included patients. A 30-day morbidity occurred in 13/47 (27.6%) patients with no mortality. Fifteen cranial nerve lesions occurred in eleven patients. The mean tumor volume was 6.92 cm³ in patients without and 15.89 cm³ in patients with complications (p = 0.035) and 7.64 cm³ in patients without and 16.28 cm³ in patients with cranial nerve injury (p = 0.05). Neither the volume nor Shamblin grade was significantly associated with complications on multivariable analysis. The AUC was 0.691, indicating a poor to fair performance of volumetry in predicting postoperative complications. Conclusions: Surgery for cervical paraganglioma bears a relevant morbidity with a particular risk of cranial nerve lesions. Tumor volume is associated with morbidity, and MRI/CT volumetry can be used for risk stratification.

Carotid body tumor encounters over a two-decade period in an academic hospital

Carotid body tumors (CBTs) are rare and mostly benign. Research outcomes usually arise from single-center data. We conducted this study to present the characteristics and outcomes of patients who underwent surgical resection of CBT at our hospital over the past 20 years. In this retrospective review, the records of CBTs in our hospital were reviewed between 1998 and 2021. All patients who underwent CBT resection were included. The follow-up period was 12 months. A total of 44 CBTs were treated in our hospital. The male-to-female ratio was 1:2.4. Only 4.5% of patients had Shamblin I tumors. Patients with Shamblin II and III tumors were 56.8% and 38.6%, respectively. Duplex scan was used to diagnose CBT in all of the patients. The majority of our patients (97.7%) did not receive any preoperative embolization despite an average tumor size of 4.9 cm. Cranial nerve injuries were observed in 29.5% of cases. Meanwhile, stroke was reported in only two cases (4.5%). No deaths were encountered. Surgery is the definitive treatment for CBT. Size and local extension appear to be the main reasons for adverse events rather than surgical techniques. Our results are consistent with those of previously published studies. Good outcomes are expected in high-volume centers with appropriate preoperative imaging.

Carotid Body Tumor: A Case Report and Review of Literature

Carotid body tumour (CBT) is a rare hypervascular tumor in the head and neck region. It develops from neural crest origin paraganglionic tissue which is an arterial chemoreceptor. It presents as a slow growing mass at the carotid bifurcation. Its optimal evaluation and treatment requires involvement of multiple specialities. Because of the high rate of neurovascular complications, resection of this tumor is challenging for surgeons. Early tumor detection, meticulous evaluation and multidisciplinary approach are vital for successful management of these tumors. A case of CBT in a 50 year-old lady managed at our centre is being reported here along with a review of literature.

Pseudocontinuous Arterial Spin Labeling: Clinical Applications and Usefulness in Head and Neck Entities

Simple Summary

Conventional imaging methods, such as ultrasonography, computed tomography, and magnetic resonance imaging may be inadequate to accurately diagnose lesions of the head and neck because they vary widely. Recently, the arterial spin labeling technique, especially pseudocontinuous arterial spin labeling (pCASL) with the three-dimensional (3D) readout method, has been dramatically developed to improve diagnostic performance for lesion differentiation, which can show prominent blood flow characteristics. Here, we demonstrate the clinical usefulness of 3D pCASL for diagnosing various entities, including inflammatory lesions, hypervascular lesions, and neoplasms in the head and neck, for evaluating squamous cell carcinoma (SCC) treatment responses, and for predicting SCC prognosis.

Abstract

As functional magnetic resonance imaging, arterial spin labeling (ASL) techniques have been developed to provide quantitative tissue blood flow measurements, which can improve the performance of lesion diagnosis. ASL does not require contrast agents, thus, it can be applied to a variety of patients regardless of renal impairments and contrast agent allergic reactions. The clinical implementation of head and neck lesions is limited, although, in recent years, ASL has been increasingly utilized in brain lesions. Here, we review the development of the ASL techniques, including pseudocontinuous ASL (pCASL). We compare readout methods between three-dimensional (3D) turbo spin-echo and 2D echo planar pCASL for the clinical applications of pCASL to head and neck lesions. We demonstrate the clinical usefulness of 3D pCASL for diagnosing various entities, including inflammatory lesions, hypervascular lesions, and neoplasms; for evaluating squamous cell carcinoma (SCC) treatment responses, and for predicting SCC prognosis.

Paragangliomas of the head and neck

Paragangliomas are rare neuroendocrine tumors that can be found from the skull base to the pelvis. Head and neck paragangliomas have been historically treated with surgery. However, surgical resection adds risk of injury to vascular structures and cranial nerves that can lead to morbidity such as hoarseness, dysarthria, dysphagia, or aspiration. Recently, improved understanding of the behavior of these tumors and increasing experience in non-surgical treatments such as observation and radiation therapy, have changed the paradigms of management of this entity. Multiple series now show a trend towards a more conservative management, with a higher percentage of patients being observed or treated with radiotherapy. Several factors should be taken into consideration when deciding the most appropriate treatment for head and neck paragangliomas, starting by differentiating carotid body tumors from non- carotid body tumors. In general, surgical resection is normally recommended for carotid body tumors as the complications from treatment are usually minimal. In contrast, for non- carotid body tumors, surgery is often associated with significant functional impairment due to cranial nerve paralysis. As such, non-surgical treatment is now usually recommended for this subset of head and neck paragangliomas. In young patients with no comorbidities and a small to medium carotid body tumors, surgery should be considered. Moreover, surgery should be offered for secreting tumors, malignant tumors, tumors with rapid growth or increase in symptomatology, and when radiotherapy cannot be performed. Conversely, conservative management with active surveillance or radiotherapy can be offered in the remaining cases in order to avoid unnecessary morbidity while still providing acceptable tumor control.

Contemporary management of paragangliomas of the head and neck

Head and neck paragangliomas (HNPGLs) are rare neuroendocrine tumors typically arising from nonsecretory head and neck parasympathetic ganglia. Historically thought of as aggressive tumors that warranted equally aggressive surgical intervention, evidence has emerged demonstrating that the vast majority of HNPGLs are slow growing and indolent. It is also now recognized that a large proportion of HNPGLs are hereditary with succinate dehydrogenase gene mutations typically implicated. These recent advances have led to significant changes in the way in which clinicians investigate and treat HNPGLs with most now opting for more conservative treatment strategies. However, a proportion of patients present with more aggressive disease and still require nonconservative treatment strategies. Recent studies have sought to determine in which groups of patients the morbidity associated with treatment is justified. We summarize the recent advances in the understanding and management of these tumors and we provide our recommendations regarding the management of HNPGLs.

Bone-destructive osseous arteriovenous fistula at the jugular bulb mimicking a glomus jugular tumor

BACKGROUND

Some reports have described intraosseous arteriovenous fistulas showing osteolytic changes, but an osseous arteriovenous fistula (AVF) at the jugular bulb showing extensive bone destruction is a very rare disease.

CASE DESCRIPTION

A 60-year-old man presented with pulsatile tinnitus and right facial nerve palsy. Radiological imaging showed a large homogenously enhanced osteolytic lesion at the right jugular foramen. A cerebral angiogram showed a high-flow vascular lesion of the jugular bulb associated with retrograde sinus reflux, resulting in venous congestion of the deep venous system. These findings led us to misdiagnose this lesion as a glomus jugular tumor. However, combined arterial and venous angiography after transarterial embolization revealed the precise angioarchitecture, and we finally diagnosed this lesion as a high-flow osseous AVF at the jugular bulb. We performed transvenous embolization using a triple catheter technique. The lesion was successfully obliterated, and the 6-months angiogram showed no recurrence.

CONCLUSION

A rare case of high flow osseous AVF at the jugular bulb associated with osteolytic changes in the surrounding bony structure is reported. Although many hypervascular lesions at the jugular bulb are glomus tumors, bone destructive osseous AVF at the jugular bulb should be considered.

FDG PET-CT imaging in head and neck paragangliomas: A centre experience

Head and neck paragangliomas (HNPGLs) are rare tumours with ~ 30% genetic mutations, mainly in succinate dehydrogenase (SDHx) genes. The utility of FDG PET-CT in HNPGLs is questioned by recent developments in novel radiotracers. We therefore performed a retrospective study in a single tertiary referral centre to address the utility of FDG PET/CT in HNPGLs.

METHODS

Clinical data on genetic testing and follow-up were collected for patients who had FDG PET-CT scans from 2004 to 2016. Receiver operator characteristic (ROC) analysis was used to compare standardized uptake values (SUVs), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) between lesions in patients who had a clinically related event: event (+) and those who did not: event (-). Similarly, we compared PET parameters between SDHx+ patients and a control group with low probability of mutation.

RESULTS

Of 153 HNPGL patients, 73 (29 SDHx+) with 93 FDG-positive lesions were identified: 53.8% of lesions were assessed in a pre-therapeutic setting. In comparison with a reference extracted from clinicoradiological database, FDG PET-CT showed good performance to detect HNPGLs (96.6% accuracy). In this study population, 16 disease progression, 1 recurrence and 1 death were recorded and event (+) patients had lesions with higher SUVmax (p = .03 and p = .02, respectively). Conversely, there were no differences in PET parameters between lesions in SDHx+ patients and controls with low probability of SDHx+ mutations.

CONCLUSIONS

FDG PET-CT has clinical utility in HNPGLs, mostly before local treatment. There were no significant differences in PET parameters between SDHx patients and a sporadic HNPGL population. However, regardless of SDHx mutation status, a high SUVmax was associated with more clinical events and prompts to a closer follow-up.

B-mode and color Doppler imaging of carotid paragangliomas in different neck regions

Glomus tumors or paragangliomas are rare benign neoplasms which are very uncommon in the head and neck region. They grow slowly from paraganglion cells, which serve various regulatory tasks in the body and form the basis of the extra-adrenal neuroendocrine system. They have benign properties, but tend to cause local invasion and expansion to adjacent anatomic structures. The majority of glomus tumor cases are incidental findings, since the clinical symptoms are mostly absent. The purpose of this paper is to distinguish the ultrasonographic features of different glomus tumors located within the neck region, based on their varying anatomical location and space occupying behavior.

Somatostatin Receptor-Targeted Radioligand Therapy in Head and Neck Paraganglioma

OBJECTIVE

Surgical resection is the therapy of choice in head and neck paraganglioma but is associated with considerable morbidity. For treatment of inoperable or progressive disease, less aggressive adjuvant options are warranted. This study assessed effectiveness and safety of peptide receptor radionuclide therapy (PRRT) with lutetium-177-DOTATATE for head and neck paraganglioma with emphasis on response assessment.

METHODS

A retrospective analysis of 7 patients with head and neck paraganglioma treated with PPRT between May 2014 and October 2016 was performed. Three patients had jugulotympanic paraganglioma, 3 patients had carotid body tumors, and 1 patient had a combination of both. Patients underwent PRRT after discussion in the local tumor board regarding progressive disease, inoperability, or lack of other adjuvant options. All patients underwent 3-5 cycles of PRRT. Treatment response was evaluated by gallium-68-DOTATATE positron emission tomography/computed tomography and contrast-enhanced computed tomography or magnetic resonance imaging. Outcome measures were two-dimensional tumor diameters and total tumor volumes.

RESULTS

Median patient age was 60 years (interquartile range: 14-84 years). All patients had stable disease at posttherapy assessment. Decreasing tumor volumes were found in 4 patients. Clinical symptoms improved in 2 patients. No progression or adverse events occurred during a median follow-up of 39 months (interquartile range: 35-47 months).

CONCLUSIONS

Somatostatin receptor-targeted therapy using lutetium-177-DOTATATE shows promising effectiveness with a high safety profile. Patients in whom surgical morbidity outweighs oncologic benefit should be informed about PRRT as a treatment option.

[Analysis of misdiagnosis glomus jugulare tumor]

Objective:To analyze the causes of misdiagnosis of patients with glomus jugulare tumor. Method:The clinical data of 116 patients with glomus jugulare tumor were retrospectively analyzed. Result:Among the 116 patients, 65 were misdiagnosed, the average duration of misdiagnosis was 4.90 years. The misdiagnosed diseases were chronic otitis media or cholesteatoma in 25 cases, neurological tinnitus or hearing loss in 16 cases, facial paralysis in 6 cases, external auditory canal masses in 4 cases, secretory otitis media in 3 cases, neck mass in 3 cases, intracranial neoplasma in 2 cases, middle ear cancer in 1 case, vocal cord paralysis in 1 case, stomatitis in 1 case, optic nerve head edema in 1 case, middle ear hemangioma in 1 case and vascular tinnitus in 1 case. Conclusion:The misdiagnosis of glomus jugulare tumor can be summarized as follows: the patients' first symptoms were not specific; lack of auxiliary examination, especially imaging examination; physicians have insufficient understanding of imaging and pathological examination of glomus jugulare tumor.

Genetics and imaging of pheochromocytomas and paragangliomas: current update

Pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare, heterogeneous neuroendocrine neoplasms of the autonomous nervous system of chromaffin cell origin that may arise within the adrenal medulla (PCCs) or the sympathetic and parasympathetic paraganglia (PGLs). Currently referred to by the umbrella term pheochromocytomas-paragangliomas (PPGLs), these distinct tumors are characterized by specific histopathology as well as biological and clinical profiles. PPGLs may occur as part of hereditary syndromes (40% of cases) or as sporadic tumors. Currently, there are 12 different hereditary syndromes with characteristic genetic abnormalities, at least 15 well-characterized driver genes and distinct tumor metabolic pathways. Based on the Cancer Genome Atlas (TCGA) taxonomic schemata, PPGLs have been classified into three main clusters of specific genetic mutations and tumor pathways with clinical, biochemical, and prognostic implications. Imaging plays a pivotal role in the initial diagnosis, tumor characterization, evaluation of treatment response, and long-term surveillance. While MDCT and MRI help in the anatomic localization, SPECT, and PET using different radiotracers are crucial in the functional assessment of these tumors. Surgery, chemotherapy, and radiotherapy are currently available treatment options for PPGLs; antiangiogenic drugs are also being used in treating metastatic disease. Evolving knowledge regarding the different genetic abnormalities involved in the pathogenesis of PPGLs has identified potential therapeutic targets that may be utilized in the discovery of novel drugs.

Carotid Body Tumor Microenvironment

Carotid body tumors (CBTs) are rare paragangliomas, comprising 0.5% of all head and neck tumors, and 65% of head and neck paragangliomas. A majority of CBTs occur sporadically, while 15% are familial or hyperplastic in the setting of chronic hypoxia. They usually present as unilateral, well-circumscribed rubbery masses, arising at the level of the carotid bifurcation. A majority of CBTs are painless and therefore may evade diagnosis for months to years. Symptomatic lesions occur due to progressive cranial nerve IX, X, or XII dysfunction, manifesting as hoarseness, dysphagia, vertigo, coughing, or odynophagia. Other local symptoms include neck discomfort, pulsatile tinnitus, hearing loss, or carotid sinus syndrome. Appropriate workup includes a thorough physical exam followed by radiographic imaging, vascular studies, and biochemical workup with 24 h urinary catecholamine or metanephrine analysis. The management of these tumors, which involves standalone surgical resection or following embolization for larger and more vascular tumors, will also be discussed.

[Diagnosis and treatment of glomus tumors of the skull base and neck]

Glomus tumors (paragangliomas) are rare, usually benign, neuroendocrine tumors that arise from nonchromaffin cells and can be multifocal or familial. They grow slowly, often infiltratively and rarely form metastases. A distinction is made between carotid, jugular, tympanicum and vagal tumors. Depending on the location, clinical symptoms include neck swelling, hearing loss with pulse-synchronous ear noise or cranial nerve failures (IX-XI). Diagnosis is often delayed because of nonspecific symptoms. Diagnostically, tumor expansion and perfusion can be well visualized by color Doppler sonography. In the T2-weighted MRI, the tumor is hyperintense, after contrast agent administration a strong enhancement occurs due to the strong vascularization. In DSA (digital subtraction angiography), even small glomus tumors can be detected. Therapeutically, operative tumor resection after embolization with, e.g., polyvinyl alcohol particles or liquid embolization can be performed. If the patient is in poor general condition or if the tumor is inoperable, different treatment techniques (intensity-modulated radiotherapy, gamma or cyber-knife) may be considered as a conservative therapeutic alternative.

The Application of Sigmoid Sinus Tunnel-packing or Push-packing of the Inferior Petrous Sinus in the Microsurgical Management of Jugular Paragangliomas

OBJECTIVE

To analyze the outcomes of microsurgically treated jugular paragangliomas with control of bleeding from the inferior petrous sinus.

STUDY DESIGN

Retrospective patient review.

SETTING

A single university hospital.

PATIENTS

Forty-three patients with jugular paragangliomas were diagnosed in the past 7 years in our clinic.

MAIN OUTCOME MEASURES

Surgical tumor control, intraoperative blood loss, intraoperative management of the facial nerve, and the preoperative and postoperative function of the lower central nerves.

RESULTS

Twenty-six patients underwent microsurgical treatment. Eighteen tumors were class C2 (69.2%), six were class C3 (23.1%), and two were class CDe1 (7.7%). Gross total tumor resection was achieved in 92.3% of the patients. The mean blood loss during surgery was 438.5 ml. The recurrence rate was 3.8% over a mean follow-up of 29.2 months. New facial palsy and lower cranial nerve deficit occurred in 42.3 and 11.5% of the patients, respectively.

CONCLUSION

The infratemporal fossa approach type A with sigmoid sinus tunnel-packing or push-packing technique facilitated the control of bleeding from the inferior petrous sinus and improved the outcomes of microsurgical treatment for jugular paragangliomas.

Carotid body paraganglioma

Carotid body paraganglioma is commonly asymptomatic, slow-growing, and nonfunctioning. With its relative contraindication to biopsy due to its high vascularity in nature, imaging characteristics are the key to help making the diagnosis. Treatment modalities, ranging from an observation to definitive treatment with surgery, should be selected on an individual basis.

Multimodality imaging of paragangliomas of the head and neck

Paragangliomas arise from paraganglion cells which serve varied regulatory tasks in the body. When these cells demonstrate neoplasia within the head and neck, they typically present in characteristic locations including the carotid space, the jugular foramen, the middle ear, and along the course of the vagus nerve. The goal of this article is to review the relevant anatomy related to head and neck paragangliomas, as well as their typical imaging characteristics on cross-sectional imaging including CT, MR, ultrasound, and nuclear medicine studies. Additionally, differential considerations, as well as relevant involvement of adjacent structures which should be conveyed to the clinician, will be discussed.

An anaesthesia perspective on carotid body tumour (CBT) excision: A twenty-year case series at the Singapore General Hospital

Carotid body tumours (CBT) are extremely rare neoplasms that arise from chemoreceptor cells at the bifurcation of the carotid artery. This rarity poses a challenge for the anaesthetist when dealing with surgeries for the removal of CBT. Reports of associated perioperative morbidity range from twenty to forty percent. This paper reviews the perioperative anaesthetic management of CBT patients and challenges in our institution's 20 year experience on 13 surgical CBT resections.

Hereditary Paraganglioma Syndrome Associated with SDHD Gene Mutations: A Patient with Multicentric Presentation Treated with Radiotherapy. Case Report

Introduction

Extra-adrenal paragangliomas are rare tumors arising from neuroendocrine cells. Sporadic and hereditary forms have been recognized. Among the latter, the PGL1 and PGL4 syndromes are associated with a high risk of multiple localizations. The treatment of choice for paragangliomas is surgical resection, but in some cases surgery can be difficult due to particular or multiple tumor sites or may result in severe neurological deficits. In such cases radiotherapy can be an effective alternative. In this paper we describe the case of a patient affected by hereditary paraganglioma syndrome with multicentric presentation who was treated at our center by external radiotherapy.

Case report

A 55-year-old man presented in April 2008 with multiple paragangliomas: one in the left pontocerebellar angle, two in the middle neck, one mediastinal paraaortic mass, and an abdominal paraaortic lesion. The left pontocerebellar and mediastinal tumors were treated with three-dimensional conformal radiotherapy (3D-CRT) at total doses of 50.40 Gy and 55.80 Gy, respectively. The neck lesions were treated with intensity-modulated radiotherapy (IMRT) at a total dose of 55.80 Gy. The abdominal paraaortic lesion was surgically resected.

Results

No severe acute or late toxicity as evaluated with the EORTC-RTOG scale was observed. Fourteen months after the end of radiotherapy a whole body CT scan showed that the tumor lesions were stable in size and in their relations to contiguous structures. The arterial pressure was controlled by medical therapy and urine catecholamine levels were within the normal range.

Conclusions

We believe that in patients affected by unresectable paragangliomas radiotherapy is a safe and effective alternative to surgery. The use of high-dose conformity techniques such as 3D-CRT and IMRT will allow higher local control rates with relatively few side effects thanks to the possibility of dose escalation and reduction of the amount of irradiated healthy tissues.

Age and Tumor Volume Predict Growth of Carotid and Vagal Body Paragangliomas

Objective  Treatment for head and neck paragangliomas (HNGPL) can be more harmful than the disease. After diagnosis, an initial period of surveillance is often indicated, and surgery or radiotherapy is reserved for progressive disease. With the aim to optimize this "wait and scan" strategy, we studied growth and possible predictors. Design  A retrospective cohort study was conducted. Setting  This study was conducted at a tertiary referral center for patients with HNGPL. Methods  Tumor volume was estimated for 184 SDHD -related carotid and vagal body paragangliomas using sequential magnetic resonance imaging. Cox regression was used to study predictors of tumor growth. Results  The estimated fraction of growing tumors ranged from 0.42 after 1 year of follow-up to 0.85 after 11 years. A median growth rate of 10.4 and 12.0% per year was observed for carotid and vagal body tumors, respectively. Tumor location, initial volume, and age ( p  < 0.05) were included in our prediction model. The probability of growth decreased with increasing age and volume, indicating a decelerating growth pattern. Conclusions  We created a prediction model (available online), enabling a more individualized "wait and scan" strategy. The favorable natural course of carotid and vagal body paragangliomas was confirmed; although with long follow-up growth will be observed in most cases.

Endovascular Approach to Glomus Jugulare Tumors

Background

Paragangliomas are benign neuroendocrine tumors derived from the glomus cells of the vegetative nervous system. Typically, they are located in the region of the jugular bulb and middle ear. The optimal management is controversial and can include surgical excision, stereotactic radiosurgery and embolization.

Case Report

We report the endovascular approach to three patients harboring glomus jugulare paragangliomas. In all cases incomplete occlusion of the lesions was achieved and recanalization in the follow-up period was revealed. Two patients presented no clinical improvement and the remaining one experienced a transient withdrawal of tinnitus.

Conclusions

It is technically difficult to achieve complete obliteration of glomus jugulare tumors with the use of embolization and the subtotal occlusion poses a high risk of revascularization and is not beneficial in terms of alleviating clinical symptoms.

Active surveillance management of head and neck paragangliomas: case series and review of the literature

Background:

Head and neck paragangliomas are rare. They are usually slow-growing, benign, non-catecholamine secreting tumours, traditionally treated with surgical excision. Complications of surgical excision include lower cranial nerve palsies, stroke and death.

Method:

A retrospective case note analysis was conducted of patients with head and neck paragangliomas treated with a watch-and-scan policy from March 2003 to September 2015, and the relevant literature was reviewed.

Results:

Fifteen head and neck paragangliomas were identified. None of the patients developed a new lower cranial nerve palsy or progression of their presenting hearing loss during the follow-up period. Five patients displayed an increase in maximum linear dimension of 4 mm over an average of 57.4 months. A review of the literature showed that a watch-and-surveillance scan policy is evolving as a treatment option for head and neck paragangliomas without malignant risk factors.

Conclusion:

Readily available surveillance scanning in head and neck paragangliomas enables the monitoring of head and neck paragangliomas, which may allow for avoidance of major surgery.

Temporal bone paragangliomas: 15 years experience

INTRODUCTION

Temporal bone paragangliomas (TBPs) are benign tumors arising from neural crest cells located along the jugular bulbus and the tympanic plexus. In general surgical excision, radiotherapy and wait-and-scan protocols are the main management modalities for TBPs.

OBJECTIVE

In this paper we aim to present our clinical experience with TBPs and to review literature data.

METHODS

The patients who were operated for tympanomastoid paraganglioma (TMP) or tympanojugular paraganglioma (TJP) in our clinic in the last 15 years were enrolled in the study. A detailed patient's charts review was performed retrospectively.

RESULTS

There were 18 (52.9%) cases with TMPs and 16 (47.1%) cases with TJPs, a total of 34 patients operated for TBPs in this time period. The mean age was 50.3± 11.7 (range 25-71 years). The most common presenting symptoms were tinnitus and hearing loss for both TMPs and TJPs. Gross total tumor resection was achieved in 17 (94.4%) and 10 (62.5%) cases for TMPs and TJPs, respectively. Five patients (31.2%) with TJP experienced facial palsy following the operation. For all the patients the mean follow-up period was 25.8 months (range 4-108 months).

CONCLUSION

In conclusion, based on our findings and literature review, total surgical excision alone or with preoperative embolization is the main treatment modality for TBPs. However radiotherapy, observation protocol and subtotal resection must be considered in cases of preoperative functioning cranial nerves, large tumors and advanced age.

Evaluation of Head and Neck Paragangliomas by Computed Tomography in Patients with Pheochromocytoma-Paraganglioma Syndromes

Background

Hereditary head and neck paragangliomas (HNP) are very often associated with pheochromocytoma-paraganglioma syndromes, which are caused by mutations in genes encoding subunits of succinate dehydrogenase (SDHx) complex.

The aim of this study was to determine the frequency and location of HNP among SDHx carriers.

Material/Methods

A total of 72 patients with SDHx mutations underwent computed tomography examinations of the head and neck. HNP were present in 44 (61.1%) out of 72 patients (31 SDHD, 11 SDHB, 2 SDHC); 113 HNP were found; the most common were carotid paragangliomas (59) and vagal paragangliomas (27).

Results

The HNP were statistically more frequent in carriers of SDHD mutations compared to carriers of SDHB mutations (72.1% vs. 43.5%, p=0.033). Multiple tumors more often occurred in patients with SDHD mutations 26/31 (83.9%) than in patients with SDHB mutations 6/11 (54.5%) p=0.05.

There was a significant difference in the prevalence of carotid paragangliomas between patients with SDHB and SDHD mutations (7/11 [63.6%] vs. 30/31 [96.8%], respectively, p=0.004). Patients with SDHD mutations more often had carotid paragangliomas located on the left side than on the right side, as compared to SDHB mutations 25/31 (80.6%) vs. 4/11 (36.4%), p=0.006.

Conclusions

SDHx mutations predispose to multifocal and bilateral HNP. Carotid and vagal paragangliomas occurred most often.

Patients with SDHD mutations are characterized by higher frequency of HNP than patients with SDHB mutations, which is mainly driven by higher frequency of carotid body tumors in patients with SDHD mutations. No difference in the frequency of head and neck paragangliomas in other locations was found.

[Head and neck paragangliomas: An interdisciplinary challenge]

BACKGROUND

Current treatment strategies for head and neck paragangliomas are moving away from radical resection and toward surgical tumor reduction, in order to preserve function and reduce morbidity. Radiotherapy modalities are alternative primary treatment options.

MATERIALS AND METHODS

A PubMed search of the relevant literature on genetics and treatment of head and neck paragangliomas was conducted.

RESULTS

The rapid progress made in genetic research was mainly triggered by two factors: firstly, the establishment of central registries for paraganglioma patients and secondly, the availability of next-generation sequencing methods. Exome sequencing and a gene-panel sequencing approach have already been successfully applied to paraganglioma syndromes. The latter method in particular is rapid and cost-effective, and may soon replace complex genotyping algorithms. The literature provides good evidence that diversified modern treatment options are available to realize individual treatment concepts for almost all paraganglioma manifestations. Generally, small and symptomatic tumors should be completely resected, particularly in younger patients. Considering the patient's age, symptoms, morbidity risk, and comorbidities, larger tumors should be surgically treated in a function-preserving manner. In these cases, primary radiotherapy is an equivalent alternative option. A "wait and scan" strategy is possible in selected cases.

DISCUSSION

The potential morbidity of surgical treatment must be weighed against the expectable quality of life. Comprehensive consultation with the patient about possible treatment modalities is mandatory. Treatment decision making should involve a multidisciplinary team of experts.

Endocrine tumors associated with the vagus nerve

The vagus nerve (cranial nerve X) is the main nerve of the parasympathetic division of the autonomic nervous system. Vagal paragangliomas (VPGLs) are a prime example of an endocrine tumor associated with the vagus nerve. This rare, neural crest tumor constitutes the second most common site of hereditary head and neck paragangliomas (HNPGLs), most often in relation to mutations in the succinate dehydrogenase complex subunit D (SDHD) gene. The treatment paradigm for VPGL has progressively shifted from surgery to abstention or therapeutic radiation with curative-like outcomes. Parathyroid tissue and parathyroid adenoma can also be found in close association with the vagus nerve in intra or paravagal situations. Vagal parathyroid adenoma can be identified with preoperative imaging or suspected intraoperatively by experienced surgeons. Vagal parathyroid adenomas located in the neck or superior mediastinum can be removed via initial cervicotomy, while those located in the aortopulmonary window require a thoracic approach. This review particularly emphasizes the embryology, molecular genetics, and modern imaging of these tumors.

Multidisciplinary Management of Carotid Body Tumors in a Tertiary Urban Institution

Objective. Aim of this study is to present the experience of our institution in carotid body tumors (CBTs) treatment. Methods. All cases treated in a Vascular Surgery Department within 2.5 years (03/2013-09/2015) were retrospectively evaluated. Demographics, diagnostic, and treatment strategy were recorded. All patients with known CBT underwent ultrasound and magnetic resonance imaging preoperatively. All cases were classified according to the Shamblin type and evaluated by a radiologist, otolaryngologist, and anesthesiologist before and after surgery. Major outcomes included mortality, stroke, cranial nerve injury, and recurrence. Results. Overall, nine patients (mean age: 59.5 ± 16.3 years) with a total of ten CBTs were treated. There was no gender prevalence and most of the cases (55%) were asymptomatic. There were no functional or familial cases. There was only one bilateral case treated in a staged manner. No preoperative embolization of CBTs was performed. Mortality and stroke rates were null. No severe complication was observed in the early and late setting. No malignancy was recorded. Mean follow-up was 15.6 ± 7.8 months. Conclusions. Multidisciplinary management of patients with CBTs is imperative for optimal results, especially in type III tumors, bilateral or functional cases. After careful treatment planning and intraoperative manipulations, complications could be avoided even without preoperative embolization.

Molecular imaging in hereditary succinate dehydrogenase mutation-related paragangliomas

Multiple paraganglioma (PGL) syndromes related to succinate dehydrogenase (SDH) gene mutations are rare hereditary conditions. These present with heterogeneous clinical signs and symptoms and in many cases are difficult to classify. We summarize the pathophysiological, clinical, laboratory, and morphological and functional imaging characteristics of SDH gene mutation PGLs, emphasizing F-FDG and F-DOPA PET/CT. We correlate clinical and genetic features of SDH-related PGLs with specific PET radiopharmaceuticals, with the aim to obtain an "individualized" diagnostic approach.

Multiple paragangliomas of head and neck associated with hepatic paraganglioma: a case report

Background

Paragangliomas (PGs) are neuroendocrine tumors derived embryonically from the neural crest cells of the autonomic nervous system. Approximately 3 % of all paragangliomas occur in the head and neck area. Head and neck paragangliomas (HNPGs) are rare and highly vascularized tumors, the majority of which are benign. Multiple HNPGs with hepatic paraganglioma are exceedingly rare.

Case presentation

We report a 59-year-old male patient with a 40-year history of an enlarged mass at the right side of the neck and two months of epigastric discomfort. Neck physical examination revealed a 6 × 6 cm, ovoid, firm mass on the right side of the neck. A pre-contrast computed tomography (CT) scan of the head and neck revealed bilateral heterogeneous soft tissue masses at the bifurcation of the carotid artery with indistinct border, the size of which was 2.4 cm × 2.6 cm on the left and 5.4 cm × 4.3 cm on the right. The lesions were intensely and heterogeneously enhanced with the internal and external carotid arteries surrounded and pushed anteriorly after contrast administration. Magnetic resonance imaging (MRI) showed a hyperintense signal on T2 weighted images compared to the surrounding muscle tissue and an intense contrast enhancement on T1 weighted images. Digital subtraction angiography (DSA) exhibited a highly vascularized masses that occupied and deformed both sides of the carotid bifurcation. As for the hepatic mass, non-contrasted CT imaging of the upper abdomen showed a 6.1 cm × 5.5 cm × 5.8 cm low density mass in the liver with indistinct border. On late arterial phase, the mass showed slight enhancement with an enlarged hepatic artery pushed around the lesion. MR imaging of the lesion in the liver demonstrated low signal intensity on T1 weighted images but heterogeneous high signal intensity on T2 weighted images. On diffusion weighted images, the mass showed high signal intensity whereas low signal intensity was seen on the image of apparent diffusion coefficient (ADC). Moreover, the contrast-enhanced MRI showed that the lesion was intensely but heterogeneously enhanced.

Conclusion

Multiple HNPGs with hepatic paraganglioma are exceedingly rare. Advanced medical imaging modalities such as ultrasound (US), CT, MR, DSA and ¹²³I-metaiodobenzylguanidine (¹²³I-MIBG) are helpful in the evaluation of the patients with PGs. Increased awareness of their concomitant occurrence and familiarity with their characteristic features are critical for clinicians and radiologists to avoid diagnostic and therapeutic pitfalls and to facilitate the early diagnosis.

Diagnosis and management of multiple paragangliomas of the head and neck

Paragangliomas (PGs) are slowly growing, usually benign neoplasms. The aim of the study was to analyze the incidence, diagnostic and therapeutic management of patients with multiple paragangliomas of the head and neck. A retrospective review of the records of 84 patients with head and neck PGs, diagnosed and treated in our institution was performed for the years 1983-2013 to identify patients with multiple tumors. Fourteen (16.6 %) patients developed multiple PGs, synchronous or metachronous, within 4-21 years of follow-up. Clinical data of these patients were reviewed to evaluate the diagnosis, location, stage and management strategy. There was a total number of 37 tumors in 14 patients. There were 20/37 (54.0 %) carotid PGs, 9/37 (24.3 %) jugular PGs and 8/37 (21.7 %) vagal PGs. Carotid PGs were observed in 12/14 (86 %) patients and in 8/14 (57 %) cases bilateral tumors occurred. Vagal PGs developed in 7/14 (50 %) patients and bilateral tumors were found in 1/14 (7 %) case. Jugular PGs occurred in 9/14 (64 %) patients. There were 30 synchronous tumors and seven metachronous PGs diagnosed 2-18 years after removal of the first tumor. Single metachronous mediastinal PG occurred. All patients had at least one tumor removed, with histopathological confirmation of the diagnosis. One patient had positive history of familial PGs. Carotid PGs are most common multiple paragangliomas. Radiological survey of the head and neck is required to detect multicentric tumors. Metachronous mediastinal and abdominal tumors may occur. Regular, prolonged follow-up is essential to identify metachronous PGs and possible postoperative gradual ICA occlusion.