Contemporary management of paragangliomas of the head and neck

Imaging of the skull base and orbital tumors

The skull base and orbit have complicated anatomical structures where various tumors can occur. The tumor may present with neurological symptoms; however, its diagnosis is clinically difficult owing to accessibility issues. Therefore, diagnostic imaging is crucial in assessing tumors in the skull base and orbit and guiding subsequent management. Notably, some tumors have a predilection for a specific site of origin, and identifying the site of origin on imaging can help narrow the differential diagnosis. At the skull base, chordomas typically occur in the clivus, chondrosarcomas in the paramedian areas, paragangliomas in the jugular foramen, neurogenic tumors, and perineural spread in the neural foramen. Among orbital tumors, cavernous hemangiomas usually occur in the intraconal space, and pleomorphic adenomas and adenoid cystic carcinomas occur in the lacrimal glands. Some skull base and orbital tumors exhibit distinctive imaging features. Chordomas and chondrosarcomas of the skull base show high signal intensities on T2-weighted images, with chondrosarcomas often displaying cartilaginous calcifications. Paragangliomas are characterized by their hypervascular nature. In the orbit, cavernous hemangiomas and pleomorphic adenomas present unique dynamic patterns. Immunoglobulin G4-related disease forms lesions along the nerves. Identifying the tumor origin and its imaging characteristics can help narrow the differential diagnosis of skull base and orbital tumors.

Clinical management and outcome of head and neck paragangliomas (HNPGLs): A single centre retrospective study

CONTEXT

Head and neck paragangliomas (HNPGLs) are rare, usually benign, slow-growing tumours arising from neural crest-derived tissue. Definitive management pathways for HNPGLs have yet to be clearly defined.

OBJECTIVE

To review our experience of the clinical features and management of these tumours and to analyse outcomes of different treatment modalities.

METHODS

Demographic and clinical data were obtained from The Northern Ireland Electronic Care Record (NIECR) as well from a prospectively maintained HNPGL database between January 2011 through December 2023.

RESULTS

There were 87 patients; 50 females: 37 males with a mean age of 52.3 ± 14.2 years old (range 17-91 years old). 58.6% (n = 51) of patients had carotid body tumours, 25.2% (n = 22) glomus vagal tumours, 6.8% (n = 6) tumours in the middle ear, 2.2% (n = 2) in the parapharyngeal space and 1.1% (n = 1) in the sphenoid sinus. 5.7% (n = 5) of patients had multifocal disease. The mean tumour size at presentation was 3.2 ± 1.4 cm (range 0.5-6.9 cm). Pathogenic SDHD mutations were identified in 41.3% (n = 36), SDHB in 12.6% (n = 11), SDHC in 2.2% (n = 2) and SDHA in 1.1% (n = 1) of the patients. Overall treatment modalities included surgery alone in 51.7% (n = 45) of patients, radiotherapy in 14.9% (n = 13), observation in 28.7% (n = 25), and somatostatin analogue therapy with octreotide in 4.5% (n = 4) of patients. Factors associated with a significantly higher risk of recurrence included age over 60 years (p = .04), tumour size exceeding 2 cm (p = .03), positive SDHx variants (p = .01), and vagal and jugular tumours (p = .04).

CONCLUSION

The majority of our patients underwent initial surgical intervention and achieved disease stability. Our results suggest that carefully selected asymptomatic or medically unfit patients can be safely observed provided lifelong surveillance is maintained. We advocate for the establishment of a UK and Ireland national HNPGL registry, to delineate optimal management strategies for these rare tumours and improve long term outcomes.

Management of bilateral head and neck paragangliomas at a single-institution across four decades

BACKGROUND

Bilateral head and neck paragangliomas (HNPGLs) require nuanced management to balance tumor control with functional preservation.

METHODS

All patients seen at a single-institution for bilateral paraganglioma between 1983 and 2023 were retrospectively reviewed. Demographics, genetic testing results, and tumor characteristics were analyzed and compared to treatment modality and cranial nerve outcomes.

RESULTS

There were 49 patients with 116 tumors (90 carotid body tumors [CBTs], 15 vagal paragangliomas [VPs], and 11 jugular paragangliomas [JPs]). Twenty-six patients had SDH pathologic variants (PV). Surgical management was more commonly utilized in younger patients (OR: 0.97, 95% CI: 0.950-0.992) and for JPs (OR: 9, 95% CI: 1.386-58.443). In surgical cases, CBTs had a lower risk of postoperative cranial nerve deficits compared to JPs and VPs (OR: 0.095, 95% CI: 0.013-0.692).

CONCLUSIONS

Younger patients with bilateral HNPGLs, especially those with JP and CBT, are more often treated with surgery. CBTs have lowest risk of cranial nerve deficits after surgery.

Single-cell RNA-Seq reveals the heterogeneity of fibroblasts within the tympanojugular paraganglioma microenvironment

Tympanojugular paragangliomas (TJP) originate from the parasympathetic ganglia in the lateral base of the skull. Although the cellular composition and oncogenic mechanisms of paragangliomas have been evaluated, a comprehensive transcriptomic atlas specific to TJP remains to be established to facilitate further investigations. In this study, single-cell RNA sequencing and whole-exome sequencing were conducted on six surgically excised TJP samples to determine their cellular composition and intratumoral heterogeneity. Fibroblasts were sub-classified into two distinct groups: myofibroblasts and fibroblasts associated with bone remodeling. Additionally, an elaborate regulatory and cell-cell communication network was determined, highlighting the multifaceted role of fibroblasts, which varies depending on expression transitions. The Kit receptor (KIT) signaling pathway mediated interactions between fibroblasts and mast cells, whereas robust connections with endothelial and Schwann cell-like cells were facilitated through the platelet-derived growth factor signaling pathway. These findings establish a foundation for studying the mechanisms underlying protumor angiogenesis and the specific contributions of fibroblasts within the TJP microenvironment. IL6 signaling pathway of fibroblasts interacting with macrophages and endothelial cells may be involved in tumor regrowth. These results enhance our understanding of fibroblast functionality and provide a resource for future therapeutic targeting of TJP.

An Unusual and Discrepant Presentation of a Skull Base Paraganglioma

Paragangliomas are rare tumors of neuroendocrine origin. Within the head and neck, these tumors are slow-growing and locally destructive, with a small malignant potential. Vagal paragangliomas (VPs) originate from paraganglia around the vagus nerve, typically at the level of the skull base. Cranial nerve deficits are common at presentation, with the vagus nerve and hypoglossal nerves being most affected. Similarly, hypoglossal paragangliomas (HPs) originate from around the hypoglossal nerve but are extremely rare and less documented. We describe the case of a patient presenting with an isolated hypoglossal nerve palsy in the setting of a tumor that radiologically represents a VP. A descriptive literature review was conducted to highlight presentation, management, and outcomes related to this pathology. A 65-year-old male presented to the clinic with tongue fasciculations and several years of dysarthria. Physical examination showed intermittent right tongue fasciculations in addition to ipsilateral hemi-atrophy. A computed tomography scan with contrast revealed an enhancing skull base mass inferior to the right carotid space. Subsequently, magnetic resonance imaging with contrast further delineated its anatomic involvement and site of origin, allowing for the diagnosis of a VP. After further discussion with the patient about his clinical findings, the decision was made to proceed with observation and serial imaging. Skull base paragangliomas are a rare pathologic entity that may pose a challenging multidisciplinary approach to optimize management strategies. Treatment may vary on a case-by-case basis and is dependent on patient and tumor characteristics.

Tumor progression in tympanojugular paragangliomas: the role of radiotherapy and wait and scan

INTRODUCTION

Tympanojugular paragangliomas (TJ PGLs) are rare tumors characterized by bone infiltration and erosion and a close relationship with critical structures, such as cranial nerves and internal carotid artery. For these reasons, their management represents a tough challenge. Since the fifties, radio-therapy (RT) has been proposed as an alternative treatment aimed at avoiding tumor progression. However, the indolent nature of the tumor, characterized by slow growth, is a crucial factor that needs to be considered before offering radiation.

METHODS

This study aims to examine tumor progression in RT patients through a systematic review of the literature and in TJ PGL patients who underwent solely wait and scan at our department.

RESULTS

The rate of tumor progression in the RT group was 8.9%, while in the wait and scan cohort was 12.9%. This data suggests the innate slow growth of PGLs. However, it is not possible to draw certain conclusions because of the wide heterogeneity of the studies.

CONCLUSION

When complete surgical excision of TJ PGLs is not feasible, appropriate counseling and patient selection, including comprehensive tumor classification, should be performed before proposing RT to control tumor progression, since wait and scan may represent a reasonable option in selected cases.

Paragangliomas of the Head and Neck: A Review of the Latest Diagnostic and Treatment Methods

Background and objectives: Paragangliomas of the head and neck are rare, slow-growing neuroendocrine tumors, benign in their vast majority, but with a possibility of developing distant metastases. They show great inheritable character, and their behavior has proven to be unpredictable; therefore, they are considered malignant. Material and methods: This article aims to offer a more comprehensive presentation of the pathogenesis, epidemiology, diagnostic methods, imaging development, and treatment guidelines. We tried to bring together all the necessary data that, in our opinion, a head and neck practitioner should know when managing this type of tumor. Our main focus is on the most recent studies, with the purpose of a homogenous presentation of all current guidelines and approaches to this pathology. Results: Paragangliomas of the head and neck are still a disputed topic. One of the main reasons for that is their low incidence of 0.3 to 1 per 100,000 every year. The most frequent locations are the carotid body, the temporal bone, the jugular and mastoid foramen, and the vagal nerve. Their clinical presentation usually involves a painless lateral mass associated with symptoms such as hoarseness, hearing loss, tinnitus, and cranial nerve deficits. Up to 40% of them are inherited, mostly linked with mutations of succinate dehydrogenase complex. Imaging evaluation consists of CT and MRI, and new functional explorations such as 18F-FDA and 18F-FDG PET/CT, 18F-DOPA PET, 123I-MIBG, and 68Ga-DOTATE PET/CT. Measuring the catecholamine levels in the plasma and urine is mandatory, even though paragangliomas of the head and neck rarely display secretory behavior. Treatment mainly consists of surgery, with different approaches and techniques, but conservative management methods such as wait and scan, radiotherapy, proton therapy, and chemotherapy have proven their efficiency. The therapeutical decision lacks consensus, and current studies tend to recommend an individualized approach. Guidelines regarding long-term follow-up are still a matter of debate.

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.

Surgical outcomes for carotid body tumour resection without preoperative embolization: a 10-year experience

Background

Carotid body tumours (CBTs) are neoplasms originating from the paraganglionic cells of the carotid body. Excision is the main route of treatment. This study sought to assess the surgical outcomes of post-carotid body tumour resection without preoperative embolization and discern any underlying relationships between modified Shamblin classes (MSC) and related complications.

Methods

A retrospective medical record review of prospectively collected data is performed at Sulaymaniyah Teaching Hospital between 2008 and 2019, for 54 patients. Presurgical and postsurgical variables such as comorbidities and complications were noted, respectively.

Results

Patient ages ranged between 26 and 60 years (x̄=40.06) with a minimal female predominance (57.4%). Complications included one minor stroke. MSC and postoperative complications were significantly related (P≤0.001). Our analyses also suggested a significant relationship between intraoperative blood loss and the incidence of postoperative complications (P=0.001, χ²=25). The MSC III subtype was significantly associated with intraoperative blood loss (P=0.000), length of stay (P=0.000), and operating time (P=0.001).

Conclusions

Our study purports a strong relationship between greater MSC and complications of all types. As such, surgeons may benefit from preoperative strategies to minimize complications.

Laryngeal Paraganglioma-A Case Report

Background and Objectives: Paragangliomas of the head and neck are rare neuroendocrine tumors originating from the paraganglia, which might be sympathetic or parasympathetic. Laryngeal paragangliomas are the rarest subtype of these tumors, with only 1.41% of all paragangliomas, arising from the supraglottic or subglottic paraganglia of the larynx. The vast majority of them are benign, but there are some cases in which they turn out to be malignant, and the only way to know with certainty the difference between them is when we identify distant metastases. The aim of this article is to share our experience with a rare case of laryngeal paraganglioma and review the clinical characteristics, methods of diagnostic, necessary investigation prior to the operation, and surgical management of this type of tumor. Materials and Methods: We present the case of a 68-year-old female patient, a non-smoker, who accused dysphagia, dysphonia, foreign body sensation, chronic cough, and hoarseness for six months. We performed a tracheostomy prior to biopsy to secure the airways in case of bleeding and then took a few biopsy samples. The histopathological exam revealed the presence of a laryngeal paraganglioma. An enhanced CT scan was performed in order to describe the localization, size, and invasion of the tumor. We also measured the vanillylmandelic acid from the urine to determine if the tumor produced catecholamines alongside a full cardiology and endocrinology examinations. In order to prevent massive bleeding during the operation, chemoembolization was attempted before surgery, but it was unsuccessful due to an anatomical variation of the left superior thyroid artery. She underwent surgery, first through transoral endoscopic microsurgery; however, we decided to undertake an external approach because of poor bleeding control, even though we had ligated both the superior thyroid artery and the external carotid artery, with a thyrotomy and laryngofissure achieving the complete resection of the tumor. Results: The patient was discharged 10 postoperative days later, with the recommendation of introducing food step-by-step from liquids to solids. She was decannulated after 30 days, with no complications regarding breathing, phonation, or deglutition. Twelve months after the surgery, we did not identify any local relapses of distant metastases. Conclusions: Laryngeal paragangliomas are rare neuroendocrine tumors that arise from the laryngeal paraganglia. Surgery is the best treatment option available, and it can be done by either an external approach or by transoral endoscopy. Enhanced CT or MRI, as well as full cardiological and endocrinological evaluation are mandatory prior to the operation. Measuring the catecholamines levels show the if the tumor is secretory. Controlling the bleeding poses the biggest challenge in performing the resection of the tumor, especially when a transoral endoscopic approach is chosen. Further standardized follow-up guidelines are required in the future.

Jugular Foramen Paragangliomas

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

Primary neuroendocrine carcinoma of cervical lymph node masquerading as non-Hodgkin lymphoma: A diagnostic challenge

ABSTRACT

A large extended family of tumors classified as neuroendocrine tumors most commonly occurs in the gastrointestinal tract and bronchus pulmonary tree. It is extremely unusual for a primary neuroendocrine tumor to present as a cervical lymph node mass at initial presentation. We discuss the rare case of a 55-year-old man who initially complained of a right neck mass that was misinterpreted as non-Hodgkin lymphoma on fine needle aspiration cytology. By integrating clinical findings, radiography, fine-needle aspiration cytology, histomorphology, and immunohistochemistry analysis, a definitive diagnosis of primary neuroendocrine carcinoma of the cervical lymph node was made. He received chemotherapy and decompressive radiation as treatment. Regarding the course of disease in the present case, the patients underwent a distant subcutaneous metastasis over the right anterior chest wall 10 months after the initial manifestation. The patient is still alive, albeit his general condition has gotten deteriorated, and he is getting regular follow-ups.

Transmastoid/Infralabyrinthine Approach to the Jugular Foramen: 2-Dimensional Operative Video

INDICATIONS CORRIDOR AND LIMITS OF EXPOSURE

This approach is intended for tumors centered in the jugular foramen with extensions between intracranial and extracranial spaces, possible spread to the middle ear, and variable bony destruction. 1,2.

ANATOMIC ESSENTIALS NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT

Jugular foramen paragangliomas are complex lesions that usually invade and fill related venous structures. They present complex relationships with skull base neurovascular structures as internal carotid artery, lower cranial nerves (CNs), middle ear, and mastoid segment of facial nerve. In this way, it is essential to perform an adequate preoperative vascular study to evaluate sinus patency and the tumor blood supply, besides a computed tomography scan to depict bone erosion.

ESSENTIAL STEPS OF THE PROCEDURE

Mastoidectomy through an infralabyrinthine route up to open the lateral border of jugular foramen, allowing exposure from the sigmoid sinus to internal jugular vein. Skeletonization of facial canal without exposure of facial nerve is performed and opening of facial recess to give access to the middle ear in way of a fallopian bridge technique. 2-10.

PITFALLS/AVOIDANCE OF COMPLICATIONS

If there is preoperative preservation of lower CN function, it is important to not remove the anteromedial wall of the internal jugular vein and jugular bulb. In addition, facial nerve should be exposed just in case of preoperative facial palsy to decompress or reconstruct the nerve.

VARIANTS AND INDICATIONS FOR THEIR USE

Variations are related mainly with temporal bone drilling depending on the extensions of the lesion, its source of blood supply, and preoperative preservation of CN function.Informed consent was obtained from the patient for the procedure and publication of his image.Anatomy images were used with permission from:• Ceccato GHW, Candido DNC, and Borba LAB. Infratemporal fossa approach to the jugular foramen. In: Borba LAB and de Oliveira JG. Microsurgical and Endoscopic Approaches to the Skull Base. Thieme Medical Publishers. 2021.• Ceccato GHW, Candido DNC, de Oliveira JG, and Borba LAB. Microsurgical Anatomy of the Jugular Foramen. In: Borba LAB and de Oliveira JG. Microsurgical and Endoscopic Approaches to the Skull Base. Thieme Medical Publishers. 2021.

An Update on Temporal Bone Paragangliomas

OPINION STATEMENT

Temporal bone paragangliomas (TBPs) are indolent, classically benign and highly vascular neoplasms of the temporal bone. There are two types of TBPs, tympanomastoid paragangliomas (TMPs) and tympanojugular paragangliomas (TJPs). The most common symptoms are hearing loss and pulsatile tinnitus. Diagnostic workup, besides conventional physical and laboratory examinations, includes biochemical testing of catecholamine and genetic testing of SDHx gene mutations as well as radiological examination. Although surgery is traditionally the mainstay of treatment, it is challenging due to the close proximity of tumor to critical neurovascular structures and thus the high risk of complications, especially in patients with advanced lesions. Radiotherapy and active surveillance have been increasingly recommended for selected patients. Decision on treatment should be made comprehensively. Curative effect depends on various factors. Long-term follow-up with clinical, laboratory, and radiological examinations is essential for all patients.

Genotype-phenotype associations in paragangliomas of the temporal bone in a multi-ethnic cohort

BACKGROUND

Temporal bone paragangliomas are rare tumours with variable presentation that can be hereditary. Identification of clinical and genetic factors of aggressive tumour behaviour is important.

OBJECTIVE

To determine the underlying genetic mutations and genotype/phenotype correlations in a multi-ethnic population of South Florida with sporadic temporal bone paragangliomas.

METHODS

In a cohort of glomus tympanicum (GT) and glomus jugulare (GJ) cases, we assessed the frequency of pathogenic single nucleotide variants, insertions, deletions, and duplications in coding exons of genes that have been associated with paragangliomas (SDHB, SDHC, SDHD, SDHA, SDHAF2, RET, NF1, VHL, TMEM127, and MAX).

RESULTS

None of the 12 GT cases had mutations. Among 13 GJ cases, we identified four mutation carriers (31%); two in SDHC, one in SDHB, and one in SDHD. All patients with pathogenic mutations were of Hispanic ethnicity, presented at a younger age (mean 27.5 versus 52.11 years), and with more advanced disease when compared to mutation-negative GJ cases.Conclusions and Significance: Mutations in the SDH genes are found in 31% of sporadic GJ. SDH-associated GJ had advanced disease and a 50% risk of metastasis. Our data supports emerging recommendations for genetic screening in all populations with GJ tumours as the genetic status informs management.

Resection of a hormonally active carotid body tumor

Treatment of carotid body tumors (CBTs) can be complicated by the presence of hormonal activity. This case describes the treatment of a 65-year-old woman that presented with an abnormally high blood pressure and was found to have a neck mass. Diagnostic imaging along with urine metanephrines revealed this mass to be a hormonally active CBT. Careful resection along with preoperative treatment with an alpha blockade allowed for a successful complete removal of the tumor without any complications. Although CBTs tend to be benign, and hormonally active tumors are rare, one must always maintain a level of suspicion of hormonal activity to prevent catastrophic operative events.

Vagal paragangliomas

PURPOSE OF REVIEW

A vagal paraganglioma is a rare head and neck tumor arising from the paraganglionic tissue within the perineurium of the vagus nerve, anywhere along the course of the nerve. Due to its proximity to the internal carotid artery, the internal jugular vein and the lower cranial nerves, this disorder poses significant diagnostic and therapeutic challenges. The diagnostic workup and management keep on evolving.

RECENT FINDINGS

This article gives a concise update of the clinical spectrum and the current state-of-the-art diagnostic workup and management of vagal paraganglioma.

SUMMARY

Every patient with suspected vagal paraganglioma needs to be evaluated by a multidisciplinary team. The management strategy is selected depending on the growth rate of the tumor, the age and fitness of the patient, the number of affected cranial nerves, the metabolic activity of the paraganglioma, and the eventual multicentricity. An algorithm guiding the clinician through the different treatment options is presented.

Targeted metabolomics detects a putatively diagnostic signature in plasma and dried blood spots from head and neck paraganglioma patients

Head and neck paragangliomas (HNPGLs), rare chemoresistant tumors curable only with surgery, are strongly influenced by genetic predisposition, hence patients and relatives require lifetime follow-up with MRI and/or PET-CT because of de novo disease risk. This entails exposure to electromagnetic/ionizing radiation, costs, and organizational challenges, because patients and relatives are scattered far from reference centers. Simplified first-line screening strategies are needed. We employed flow injection analysis tandem mass spectrometry, as used in newborn metabolic screening, to compare the plasma metabolic profile of HNPGL patients (59 samples, 56 cases) and healthy controls (24 samples, 24 cases). Principal Component Analysis (PCA) and Partial Least Discriminant Analysis (PLS-DA) highlighted a distinctive HNPGL signature, likely reflecting the anaplerotic conversion of the TCA cycle to glutaminolysis and catabolism of branched amino acids, DNA damage and deoxyadenosine (dAdo) accumulation, impairment of fatty acid oxidation, switch towards the Warburg effect and proinflammatory lysophosphatidylcholines (LPCs) signaling. Statistical analysis of the metabolites that most impacted on PLS-DA was extended to 10 acoustic neuroma and 2 cholesteatoma patients, confirming significant differences relative to the HNPGL plasma metabolomic profile. The best confusion matrix from the ROC curve built on 2 metabolites, dAdo and C26:0-LPC, provided specificity of 94.29% and sensitivity of 89.29%, with positive and negative predictive values of 96.2% and 84.6%, respectively. Analysis of dAdo and C26:0-LPC levels in dried venous and capillary blood confirmed that dAdo, likely deriving from 2'-deoxy-ATP accumulated in HNPGL cells following endogenous genotoxic damage, efficiently discriminated HNPGL patients from healthy controls and acoustic neuroma/cholesteatoma patients on easily manageable dried blood spots.

Surgical and non-surgical management of thoracic and cervical paraganglioma

Thoracic and cervical paragangliomas (PGLs) are rare neuroendocrine tumors arising from chromaffin cells of the neural crest progenitors located outside the adrenal gland. We describe our current protocol as a multidisciplinary team for the management of cervical and thoracic PGLs. Surgery is generally considered the treatment of choice as it offers the best chance for cure. For resection of thoracic PGLs, video-assisted thoracoscopic surgery (VATS) is the main surgical approach, while open thoracotomy is preferred in case of tumors > 6cm, lacking confirmation of a plane of separation with adjacent structures, or with technical difficulties during VATS. In cervical PGLs, the surgical approach should be individualized according to location, mainly based on the Glasscock-Jackson and the Fisch-Mattox classifications. Surgery is the treatment of choice for most cervical and thoracic PGLs, but radiotherapy or observation could be more suitable options in unresectable cervical and thoracic PGLs or when resection has been incomplete.