Succinate dehydrogenase mutations in head and neck paragangliomas: A systematic review and meta-analysis of individual patients' data

BACKGROUND

Head and neck paragangliomas (HNPs) have been associated with gene mutations in the succinate dehydrogenase (SDH) complex, but the clinical significance remains unclear. We sought to explore the demographics, clinical characteristics, treatment methods, and outcomes of SDH-mutated HNPs.

METHODS

Databases were systematically searched. Pooled event ratio and relative 95% confidence intervals were calculated for dichotomous outcomes. Meta-regression was performed. Cochran's Q test and I2 test assessed heterogeneity. Funnel plot and Egger's regression test assessed publication bias.

RESULTS

Forty-two studies with 8849 patients were included. Meta-regression revealed a significant correlation between multifocality and SDHD mutations (0.03 ± 0.006, p < 0.0001) and between distant metastases and SDHB mutations (0.06 ± 0.023, p = 0.008). There was no correlation between sex, age, tumor size, or familial occurrences and SDH-related mutations.

CONCLUSION

Multifocality of HNPs correlates with the SDHD mutational subtype, and metastases correlate with the SDHB subtype. Knowledge of HNP phenotypes associated with SDH-related mutations has the potential to influence the management approach to such HNPs.

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.

Paraganglioma of the Neck: A Rare Case With Spinal Metastasis

Paragangliomas are rare neuroendocrine tumors that arise from the paraganglia, which are clusters of neuroendocrine cells associated with the autonomic nervous system. These tumors are commonly found in the adrenal medulla but can also occur in other locations outside the adrenal gland. Here, we present a case report of a slow-growing paraganglioma in the left neck with spinal metastasis in a 60-year-old man. This case highlights the importance of considering paraganglion tumors in the differential diagnosis of neck masses and the need for early diagnosis and management to prevent potential complications. Importantly, both the clinical picture and anatomical location of these tumors is important when determining treatment plans.

Head and Neck Paragangliomas: Overview of Institutional Experience

Head and neck paragangliomas (HNPGLs) are rare and have high rates of genetic mutations. We conducted a retrospective review of 187 patients with 296 PGLs diagnosed between 1974 and 2023. The mean age of diagnosis was 48.8 years (range 10 to 82) with 69.0% female and 26.5% patients with multiple PGLs. Among 119 patients undergoing genetic testing, 70 (58.8%) patients had mutations, with SDHB (30) and SDHD (26) being the most common. The rates of metastasis and recurrence were higher among patients with SDHB mutations or SDHD mutations associated with multiple PGLs. Metabolic evaluation showed elevated plasma dopamine levels were the most common derangements in HNPGL. MRI and CT were the most common anatomic imaging modalities and DOTATATE was the most common functional scan used in this cohort. Most patients (81.5%) received surgery as the primary definitive treatment, while 22.5% patients received radiation treatment, mostly as an adjuvant therapy or for surgically challenging or inoperable cases. Systemic treatment was rarely used in our cohort. Our single-center experience highlights the need for referral for genetic testing and metabolic evaluation and for a team-based approach to improve the clinical outcomes of patients with HNPGLs.

Management of phaeochromocytoma and paraganglioma in patients with germline SDHB pathogenic variants: an international expert Consensus statement

Adult and paediatric patients with pathogenic variants in the gene encoding succinate dehydrogenase (SDH) subunit B (SDHB) often have locally aggressive, recurrent or metastatic phaeochromocytomas and paragangliomas (PPGLs). Furthermore, SDHB PPGLs have the highest rates of disease-specific morbidity and mortality compared with other hereditary PPGLs. PPGLs with SDHB pathogenic variants are often less differentiated and do not produce substantial amounts of catecholamines (in some patients, they produce only dopamine) compared with other hereditary subtypes, which enables these tumours to grow subclinically for a long time. In addition, SDHB pathogenic variants support tumour growth through high levels of the oncometabolite succinate and other mechanisms related to cancer initiation and progression. As a result, pseudohypoxia and upregulation of genes related to the hypoxia signalling pathway occur, promoting the growth, migration, invasiveness and metastasis of cancer cells. These factors, along with a high rate of metastasis, support early surgical intervention and total resection of PPGLs, regardless of the tumour size. The treatment of metastases is challenging and relies on either local or systemic therapies, or sometimes both. This Consensus statement should help guide clinicians in the diagnosis and management of patients with SDHB PPGLs.

Paraganglioma of the Recurrent Laryngeal Nerve

Background/Objective

Paragangliomas are rare neuroendocrine tumors that primarily arise in the adrenal gland. Head and neck paragangliomas comprise approximately 3% of all extra-adrenal paragangliomas, with a majority of those being found in the carotid body. Recurrent laryngeal nerve paragangliomas are exceedingly rare, with only 2 reported cases found in literature review. Here, we will present the third.

Case Report

The patient is a 46-year-old woman with a history of a right thyroid nodule that had been previously biopsied benign with "paucity of diagnostic material." Neck ultrasonography revealed a 7.4 cm nodule that demonstrated interval growth over a 2-year period, so it was recommended to proceed with right thyroid lobectomy and isthmusectomy. During resection, the recurrent laryngeal nerve appeared to "disappear" into the nodule, and it was resected along with the nodule to ensure proper margins. The nerve was reconstructed with an ansa cervicalis interposition graft, and the nodule was sent to pathology. Pathology revealed that the nodule was a 4.8 cm paraganglioma of the recurrent laryngeal nerve.

Discussion

Paragangliomas of the head and neck are exceedingly rare. In patients who present with symptoms of dysphagia or dysphonia, further workup, including laryngoscopy and magnetic resonance imaging, could potentially identify and allow for appropriate planning for surgical resection.

Conclusion

In rare cases, consideration of paraganglioma as part of the differential for thyroid nodules may assist with planning of surgery but will unlikely alter treatment.

Multi-Disciplinary Approach to Skull Base Paragangliomas

The treatment of skull base paragangliomas has moved towards the use of cranial nerve preservation strategies, using radiation therapy and subtotal resection in instances when aiming for gross total resection would be expected to cause increased morbidity compared to the natural history of the tumor itself. The goal of this study was to analyze the role of surgery in patients with skull base paragangliomas treated with CyberKnife stereotactic radiosurgery (SRS) for definitive tumor control. A retrospective review identified 22 patients (median age 65.5 years, 50% female) treated with SRS from 2010-2022. Fourteen patients (63.6%) underwent microsurgical resection. Gross total resection was performed in four patients for tympanic paraganglioma (n = 2), contralateral paraganglioma (n = 1), and intracranial tumor with multiple cranial neuropathies (n = 1). Partial/subtotal resection was performed for the treatment of pulsatile tinnitus and conductive hearing loss (n = 6), chronic otitis and otorrhea (n = 2), intracranial extension (n = 1), or episodic vertigo due to perilymphatic fistula (n = 1). Eighteen patients had clinical and imaging follow-up for a mean (SD) of 4.5 (3.4) years after SRS, with all patients having clinical and radiological tumor control and no mortalities. Surgery remains an important component in the multidisciplinary treatment of skull base paraganglioma when considering other outcomes besides local tumor control.

Paragangliomas and Anemia: Literature Review and Case Report

Paragangliomas are rare neuroendocrine tumors that arise from the extra-adrenal autonomic paraganglia, i.e., small organs consisting mainly of neuroendocrine cells that are derived from the embryonic neural crest and have the ability to secrete catecholamines. Paragangliomas can derive from either parasympathetic or sympathetic paraganglia. Most of the parasympathetic ganglia-derived paragangliomas are nonfunctional, and symptoms result from mass effect. Conversely, the sympathetic paragangliomas are functional and produce catecholamine. Although such patients could have symptoms similar to pheochromocytoma, mass effect symptoms, or non-specific symptoms, being benign tumors, they can also present with anemia, specifically iron-deficiency anemia. Considering that neoplastic pathology is chronically accompanied by moderate, normochromic, normocytic anemia, association between paragangliomas that are mostly benign but with a potential degree of malignancy and anemia is not as frequent as expected, with only 12 cases reported in the literature. We report a case of a 54-year-old female patient diagnosed with a paraganglioma of the carotid glomus accompanied by severe normochromic, normocytic anemia, which reached normal limits after excision of the paraganglioma.

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.

Clinical consensus guideline on the management of phaeochromocytoma and paraganglioma in patients harbouring germline SDHD pathogenic variants

Patients with germline SDHD pathogenic variants (encoding succinate dehydrogenase subunit D; ie, paraganglioma 1 syndrome) are predominantly affected by head and neck paragangliomas, which, in almost 20% of patients, might coexist with paragangliomas arising from other locations (eg, adrenal medulla, para-aortic, cardiac or thoracic, and pelvic). Given the higher risk of tumour multifocality and bilaterality for phaeochromocytomas and paragangliomas (PPGLs) because of SDHD pathogenic variants than for their sporadic and other genotypic counterparts, the management of patients with SDHD PPGLs is clinically complex in terms of imaging, treatment, and management options. Furthermore, locally aggressive disease can be discovered at a young age or late in the disease course, which presents challenges in balancing surgical intervention with various medical and radiotherapeutic approaches. The axiom-first, do no harm-should always be considered and an initial period of observation (ie, watchful waiting) is often appropriate to characterise tumour behaviour in patients with these pathogenic variants. These patients should be referred to specialised high-volume medical centres. This consensus guideline aims to help physicians with the clinical decision-making process when caring for patients with SDHD PPGLs.

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.

Carotid body tumors: A retrospective case series of 11 patients

BACKGROUND

Carotid body tumors (CBTs) are uncommon neuroendocrine tumors located near the carotid bifurcation within the carotid body. CBTs are slow-growing; affected individuals may remain asymptomatic for years and are often diagnosed incidentally following imaging studies. When present, symptoms are nonspecific. Because incidence is low, retrospective review of CBT case series is an ideal study design for investigating common symptomology, identifying successful diagnostic tools, and evaluating treatment outcomes.

METHODS

This article describes a case series of 11 patients treated for CBTs at an academic medical center in the Southeastern US. A retrospective chart review of 11 patients who had been discharged from the hospital following treatment for CBTs between 2017 and 2021 was conducted. Descriptive statistics were used to delineate the case series.

RESULTS

There were four males (36%) and seven females (64%) included in the retrospective case series. The age range was 34 to 79 with a mean of 56.73 (standard deviation 16.038). Three patients were found to have a neck mass on physical exam. Additional symptoms included vocal cord paralysis, facial paralysis, ischemic stroke, Bell palsy, dysphonia, and dizziness. Two patients had familial CBTs. Ten patients underwent surgical excision.

CONCLUSION

This case series showed that patients with CBTs should be assessed with a combination of history and physical exams along with imaging studies to confirm the diagnosis. Because CBTs may become malignant and metastasize, it is important for NPs to be knowledgeable about presenting symptoms and appropriate diagnostic studies to be able to refer patients to vascular surgeons early to prevent complications.

Comparison of surgical outcomes between early and advanced class of jugular paragangliomas following application of our modified surgical techniques

To compare the safety and effectiveness of surgical treatment of jugular paragangliomas (JPs) following the application of our modified surgical techniques. Fifty-six patients with JPs were analyzed for tumor classification, surgical outcomes, and intratumor blood vessels. The gross total resection in C1-2 (100%) was significantly greater than that in C3 and D (66.7%). Good postoperative facial nerve (FN) function (House-Brackmann I-II) was achieved in 89.5% C1-2 cases, which was not significantly different from C3 and D (93.3%) (P = 0.694). Preoperative and postoperative lower cranial nerve (LCN) deficits correlated with the Fisch's classification of tumors (P < 0.05), and intraoperative blood loss was greater in advanced tumors (P = 0.050). Further study showed that the cross-sectional area of intratumor blood vessels was positively associated with intraoperative blood loss (P < 0.001). Surgical excision of JPs is a safe and effective strategy, and early surgical treatment is a good option for patients with C1-2 tumors without surgical contraindications.

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.

Non-Functional Carotid Body Tumors in Patients Without Somatic Mutations May Be Considered for Non-Operative Management

BACKGROUND

Carotid Body Tumors (CBT) are rare neuroendocrine paragangliomas which are typically asymptomatic and benign, with a low rate of biochemical functionality. Historically, early surgical excision was recommended to prevent development of CBT-related complications. Yet, CBT resection can result in significant cranial nerve and vascular injuries. Recent work has shown successful primary observation without resection of non-carotid body, cranial paragangliomas with slow growth and low rate of neuropathies. We hypothesize that primary observation of CBT is safe and may be considered for majority of CBT.

METHODS

Retrospective cohort study of patients at a multi-hospital healthcare system with radiologic identification and/or diagnostic or procedural billing codes for CBT (2000-2019). Tumor size (greatest diameter), associated symptoms, and interventions were recorded at the initial evaluation and throughout follow-up. Multivariable logistic regression investigated the risk of initial surgical resection.

RESULTS

A total of 108 patients (mean age, 59 ± 19 years; 67% female), with 123 CBT (mean diameter 23 ± 12 mm; 52% right) were initially evaluated by otolaryngologists (51%), vascular surgeons (25%), neurosurgeons (8%), or other (16%) medical providers. Fity-five CBT were initially resected, 63 observed, and 5 irradiated. Initial resection was associated with younger age (adjusted odd ratios aOR, 0.95 [95% confidence intervals CI, 0.92-0.97]), male sex (aOR, 4.82 [95% CI, 1.47-15.75]), and evaluation by a vascular surgeon (aOR, 6.17 [95% CI, 2.04-18.63]). Overall median follow-up was 4.7 (IQR, 2.6-9.1) years. Initially observed CBT were on an average stable in size (mean 1 ± 5 mm/year), none became biochemically active, and 2 patients became symptomatic. At the final follow-up, 63 (51%) underwent surgical resection, 54 (44%) observation, and 6 (5%) radiation therapy. Of the 63 surgically resected CBT, 5 (8%) patients had malignant CBT of which 3 (60%) had known somatic mutations (polymerase epsilon [n = 1], succinate dehydrogenase-D gene [n = 2]). Thirty percent of CBT resections had in-hospital postoperative complications, notably including 1 stroke which occurred in an initially observed patient and 16 cranial nerve complications which all occurred in immediately resected patients. Three resected CBT locally recurred, only 1 of which had malignant pathology.

CONCLUSIONS

Patients with newly diagnosed CBT require biochemical functionality and somatic mutation testing. In the absence of these findings, initial observation of CBTs with annual imaging and symptom monitoring may be considered an alternative to immediate resection which demonstrates a high risk of clinically meaningful postoperative complications.

A Case for Genetic Testing in Isolated Tympanic Paragangliomas

OBJECTIVE

The aim of this study is to describe two clinical cases, which we believe highlight the need to consider routine genetic testing of all patients with new diagnosis of a tympanic paraganglioma (PGL).

PATIENTS

Two patients seen in the ENT clinic at a tertiary center with a diagnosis of isolated tympanic PGL, without family history.

INTERVENTION

Since 2016, all patients with newly diagnosed isolated tympanic PGL (glomus tympanicum) are offered review by the clinical genetic team and genetic testing of a panel of paraganglioma/phaeochromocytoma predisposition genes. Previously only those with multiple PGL or a family history were tested.

MAIN OUTCOME MEASURES

We describe the results of genetic testing, the clinical course and discuss the ongoing implications for management.

RESULTS

Both cases were identified to have a pathogenic variant in the SDHB gene after initial surgery. The clinical course for both cases was complicated by disease recurrence, as well as metastatic and secretory disease in one case. Knowledge of genetic status has influenced ongoing management, with annual MRI surveillance for other SDH-related tumors.

CONCLUSION

These two cases reinforce the importance of offering genetic testing for all cases of isolated tympanic PGL. The discovery of a significant underlying genetic variant may affect management decisions and subsequent follow-up.

Efficacy and safety of preoperative embolization in carotid body tumor treatment: A propensity score matching retrospective cohort study

BACKGROUND

To assess the efficacy and safety of preoperative embolization (PE) in patients with carotid body tumor (CBTs).

METHODS

In a single-center retrospective cohort study, 127 patients underwent surgical resection of CBTs from January 2003 to December 2019. One-to-one propensity score matching was conducted between patients with or without PE.

RESULTS

Thirty-two (25.2%) patients received PE. After propensity score matching, no statistically significant differences were found in the baseline characteristics of 28 patients in each group. Compared with NPE group, operative time and estimated blood loss (EBL) were significantly reduced in the PE group. The incidence of stroke, perioperative complications, intraoperative blood transfusion, vascular reconstruction, hospital stay, tumor recurrence, and all-cause mortality were not different between the PE and NPE group.

CONCLUSIONS

Preoperative embolization was efficient and safe with a reduction of intraoperative blood loss and operative time during CBT resection.

SDHC phaeochromocytoma and paraganglioma: A UK-wide case series

OBJECTIVE

Phaeochromocytomas and paragangliomas (PPGL) are rare, but strongly heritable tumours. Variants in succinate dehydrogenase (SDH) subunits are identified in approximately 25% of cases. However, clinical and genetic information of patients with SDHC variants are underreported.

DESIGN

This retrospective case series collated data from 18 UK Genetics and Endocrinology departments.

PATIENTS

Both asymptomatic and disease-affected patients with confirmed SDHC germline variants are included.

MEASUREMENTS

Clinical data including tumour type and location, surveillance outcomes and interventions, SDHC genetic variant assessment, interpretation, and tumour risk calculation.

RESULTS

We report 91 SDHC cases, 46 probands and 45 non-probands. Fifty-one cases were disease-affected. Median age at genetic diagnosis was 43 years (range: 11-79). Twenty-four SDHC germline variants were identified including six novel variants. Head and neck paraganglioma (HNPGL, n = 30, 65.2%), extra-adrenal paraganglioma (EAPGL, n = 13, 28.2%) and phaeochromocytomas (PCC) (n = 3, 6.5%) were present. One case had multiple PPGLs. Malignant disease was reported in 19.6% (9/46). Eight cases had non-PPGL SDHC-associated tumours, six gastrointestinal stromal tumours (GIST) and two renal cell cancers (RCC). Cumulative tumour risk (95% CI) at age 60 years was 0.94 (CI: 0.79-0.99) in probands, and 0.16 (CI: 0-0.31) in non-probands, respectively.

CONCLUSIONS

This study describes the largest cohort of 91 SDHC patients worldwide. We confirm disease-affected SDHC variant cases develop isolated HNPGL disease in nearly 2/3 of patients, EAPGL and PCC in 1/3, with an increased risk of GIST and RCC. One fifth developed malignant disease, requiring comprehensive lifelong tumour screening and surveillance.

Glomus jugulare in a pediatric patient: case report and literature review

PURPOSE

The jugular and tympanic glomus are rare neoplasms in the general population, being even more uncommon in the pediatric population. There is considerable morbidity associated with both disease and treatment. Treatment is essentially surgical, carried out in recent years in a multidisciplinary manner using preoperative embolization associated with microsurgery and eventually adjuvant radiotherapy. The outcome depends on the location of the lesion and its proximity to noble structures in addition to multidisciplinary monitoring in the postoperative period.

METHODS

In this article, a literature review was carried out in the PubMed database, finding reports from 17 patients diagnosed with the disease. Only articles in English were considered.

RESULTS

Moreover, we reported a case of a 14-year-old patient diagnosed with jugulotympanic glomus who underwent radical surgical treatment of the lesion.

CONCLUSION

This is a rare case of jugulotympanic glomus in a pediatric patient, who underwent surgical treatment associated with multidisciplinary therapy, with a favorable postoperative outcome.

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.

Magnetic resonance imaging of the cranial nerves in infectious, neoplastic, and demyelinating diseases, as well as other inflammatory diseases: a pictorial essay

The cranial nerves, which represent extensions of the functional structures of the brain, traverse the head and neck. They are connected to various cranial structures and are associated with several diseases. An in-depth understanding of their complex anatomy and normal imaging appearance allows the examiner to identify and characterize abnormalities with greater precision. One important tool for evaluating the cranial nerves is contrast-enhanced magnetic resonance imaging, especially that employing three-dimensional steady-state free precession sequences, which provide high soft-tissue and spatial resolution, despite the slen-derness of the nerves. In most cases of cranial nerve abnormalities, the imaging findings are nonspecific. Therefore, to narrow the differential diagnosis, it is necessary to take a full patient history, perform a focused physical examination, and order laboratory tests. In this pictorial essay, we review, illustrate, and discuss, from a pathophysiological perspective, infectious, neoplastic, and demyelinating disorders, as well as other inflammatory disorders, affecting the cranial nerves, the aim being to provide a practical, tangible reference for radiologists to use in daily practice.

Radiotherapy of benign intracranial tumours

We present the updated recommendations of the French Society for Radiation Oncology on benign intracranial tumours. Most of them are meningiomas, vestibular schwannomas, pituitary adenomas, craniopharyngiomas, and glomus tumours. Some grow very slowly, and can be observed without specific treatment, especially if they are asymptomatic. Symptomatic or growing tumours are treated by surgery, which is the reference treatment. When surgery is not possible, due to the location of the lesion, or general conditions, radiotherapy can be applied, as it is if there is a postoperative growing residual tumour, or a local relapse. Indications have to be discussed at a multidisciplinary panel, with precise evaluation of the benefit and risks of the treatments. The techniques to be used are the most modern ones, as multimodal imaging and image-guided radiation therapy. Stereotactic treatments, using fractionated or single doses depending on the size or the location of the tumours, are commonly realized, to avoid as much a possible the occurrence of late side effects.

Imaging of Petrous Apex Lesions

The petrous apex may be affected by a range of lesions, commonly encountered as incidental and asymptomatic findings on imaging performed for other clinical reasons. Symptoms associated with petrous apex lesions commonly relate to mass effect and/or direct involvement of closely adjacent structures. Petrous apex lesions are optimally assessed using a combination of high-resolution CT and MRI of the skull base. Management of petrous apex lesions varies widely, reflecting the range of possible pathologies, with imaging playing a key role, including lesion characterization, surveillance, surgical planning, and oncological contouring.

Functional Outcomes Following Delayed Laryngeal Reinnervation Of Patients with Vagal Paralysis After Paraganglioma and Schwannoma Surgery

PURPOSE

We present a prospective case series that aimed to report the functional (voice and swallowing) outcomes of delayed laryngeal reinnervation following vagal interruption by resection of vagal paraganglioma and schwannoma.

MATERIALS AND METHODS

A dedicated, anonymized database was established in 2012 with a minimum eighteen-month follow up set for this report. Internationally validated self- and observer-reported measures were recorded preoperatively and at six, 12 and, 18 months together with demographics, diagnoses, and operative details.

RESULTS

A total of eight patients with a median age of 46 (37-54) underwent excision of vagal paraganglioma (five) and schwannoma (three) with few mild complications. Three underwent selective and five non selective reinnervation. Seven out of eight patients underwent synchronous injection medialization. The voice handicap index (VHI-30) improved from a baseline median 83 (range 52-102) to 7.5 (5-58) at 18 months; maximum phonation time improved from median 8 (range 5-15) to 10.5 (8.5-11); voice grade ("G" in grade, roughness, breathiness, asthenia, and strain [GRBAS] scoring) improved from median three (severe impairment, range 0-3) to one (mild impairment, 0-2); Eating Assessment Tool (EAT-10) score improved from median 12 (range 3.5-27) preoperatively to one (0-16); and reflux symptom index (RSI) improved from median 25 (range 17-36) to 7 (0-36). One patient exhibited no discernible reinnervation, while the remainder exhibited good cord bulk and tone, though without purposive abduction.

CONCLUSION

Delayed laryngeal reinnervation for high vagal paralysis is a safe technique associated with good voice and swallowing outcomes by 12-18 months. Potential confounders in this small series and the absence of a control arm both limit conclusions, but this study suggests that further prospective, controlled studies, and/or case registration are merited.