Malignant head/neck paragangliomas. Comparative Study

Functional vagal paraganglioma developing 15 years after resection of a retroperitoneal paraganglioma

The patient, a 40-year-old woman, was diagnosed as having a functional right vagal paraganglioma (PGL) 15 years after undergoing resection for a retroperitoneal PGL. 123I-MIBG scintigraphy showed no accumulation, but as the blood noradrenaline and urinary normetanephrine concentrations were elevated, the tumor was judged as being functional, and surgery was scheduled. The patient was started on doxazosin infusion and embolization of the tumor feeding vessel was performed before the surgery. Intraoperative examination showed that the tumor was contiguous with the vagal nerve, necessitating combined resection of the vagal nerve with the tumor. Postoperatively, the catecholamine levels returned to normal range. Histopathologically, the tumor was diagnosed as a moderately differentiated, intermediate-malignant-grade PGL, with a GAPP score of 4 to 6. No non-chromaffin tissue was observed in the tumor background, so that the functional vagal PGL was considered as a sporadic metachronous tumor rather than as a metastasis from the retroperitoneal PGL. More than half of head and neck paragangliomas (HNPGLs) are reported to arise in the carotid body, and about 5% from the vagal nerve. In addition, HNPGLs rarely produce catecholamines. Herein, we consider the relationship with the previously resected retroperitoneal PGL based on a review of the literature.

Long-Term Surgical Outcome of Class A and B Tympanomastoid Paragangliomas

OBJECTIVE

To analyze the long-term facial function as well as overall postoperative condition in surgically treated tympanomastoid PGL patients.

STUDY DESIGN

Retrospective study.

METHOD

The medical records of patients with surgically managed class A and B tympanomastoid PGLs between 1983 and 2023 were thoroughly evaluated.

RESULT

Our center has treated a total of 213 cases of tympanomastoid PGL surgically. The mean age of patients was 54, and the male-to-female ratio was 1:6. The most common symptoms at presentation were hearing loss (80%), pulsatile tinnitus (77%), and vertigo (15%). According to the modified Fisch classification, 45% of the cases were classified as class A (A1 and A2), while 55% were classified as class B (B1, B2, and B3). All class A and most class B1 and B2 tumors were removed either with transcanal or retroauricular-transcanal approaches. However, more advanced class B3 lesions were removed with subtotal petrosectomy (SP) along with middle ear obliteration. Facial nerve outcome was excellent in all class A and B cases, while chances of postoperative paresis slightly increased with the size and extent of the tumor (p < 0.05). The hearing outcome is excellent for class A1, A2, B1, and B2 tumors, whereas more advanced class B3 cases have a loss of air conduction (AC) and increased bone conduction (BC) threshold (p < 0.05). Complete surgical removal was achieved in 97% of our cases. The most common late complication was permanent TM perforation (7%), and the recurrence rate was 3%.

CONCLUSIONS

Tympanomastoid PGL represents the most common neoplasm of the middle ear space. The most frequent presenting symptoms include pulsatile tinnitus and hearing loss, whereas the presence of retrotympanic mass was evident in all cases at the time of initial otoscopic evaluation. Proper documentation of facial function and audiometric evaluation are crucial elements of preoperative workup. The most preferred preoperative radiologic examination is high-resolution computer tomography (HRCT), whereas magnetic resonance imaging (MRI) with or without gadolinium enhancement is reserved for cases with a dilemma of carotid artery or jugular bulb involvement. The main goal of tympanomastoid PGL treatment is complete disease removal with preservation of hearing and facial functions. Surgical treatment remains the preferred treatment modality with the benefits of complete disease removal, lower rate of recurrence and complication, and acceptable postoperative hearing level. Here, we present our 40 years of experience, which, to the very best of our knowledge, is the largest series of tympanomastoid PGL in the English literature.

Malignant carotid body tumors: What we know, what we do, and what we need to achieve. A systematic review of the literature

Malignant carotid body tumors (MCBT) are rare and diagnosed after detection of nodal or distant metastases. This systematic review (SR) focuses on MCBT initially approached by surgery. Preferred Reporting Items for SR and Meta-Analysis (MA) guided the articles search from 2000 to 2023 on PubMed, Scopus, and Web of Science. Among 3548 papers, 132 (337 patients) were considered for SR; of these, 20 (158 patients) for MA. Malignancy rate was 7.3%, succinate dehydrogenase (SDH) mutation 17%, age at diagnosis between 4th and 6th decades, with a higher prevalence of females. MCBTs were mostly Shamblin III, with nodal and distant metastasis in 79.7% and 44.7%, respectively. Malignancy should be suspected if CBT >4 cm, Shamblin III, painful or otherwise symptomatic, at the extremes of age, bilateral, with multifocal disease, and SDHx mutations. Levels II-III clearance should be performed to exclude nodal metastases and adjuvant treatments considered on a case-by-case basis.

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.

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.

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.

Report of a vagal paraganglioma at the cervicothoracic junction

BACKGROUND

Vagus nerve paragangliomas are rare tumors, comprising 0.03% of head and neck neoplasms. These tumors are usually located cephalad to the hyoid bone, and there is only one previously reported case that arose from the lower third of the neck.

METHODS

We describe the second reported case of a lower neck vagus nerve paraganglioma that was managed with a limited sternotomy for access and surgical removal.

RESULTS

A 66-year-old male presented with a long-standing lesion of the cervicothoracic junction. CT, MRI, and Ga-68 DOTATATE PET/CT showed an avidly enhancing 5.2 × 4.2 × 11.5 cm mass extending from C6 to approximately T4 level. FNA confirmed the diagnosis. The patient underwent catheter angiography and embolization via direct puncture technique followed by excision of the mass via a combined transcervical and limited sternotomy approach.

CONCLUSION

We describe an unusual case of vagal paraganglioma at the cervicothoracic junction with retrosternal extension requiring a sternotomy for surgical excision.

Can Superoxide Anions Predict the Malignant Potential of Carotid body Tumor? - A Pilot Study

Currently, there is no consensus on estimating the malignant potential of Carotid Body Tumor (CBT) and the only way to predict a metastatic CBT is through DOTANOC Positron Emission Tomography (PET) scan. There is a well-established correlation between CBT and superoxide anions inside tumor cells. The purpose of this pilot study was to measure superoxide anions inside CBT cells and find if these can be used as marker to predict malignant potential of CBT. The results were also co-related with findings of DOTANOC PET scan retrospectively. The CBT tissue from 10 patients was stained using a fluorogenic dye and superoxide anions were measured by analysis of fluorescent image. The patients were divided into two groups - First group with four patients having potentially malignant CBT based upon clinico-surgical characteristics and second group with the rest of the six patients. It was seen that the superoxide anions were highest in the first group which included patients with metastatic carotid body tumor, patients with multiple paragangliomas and patient with positive family history (p = 0.011). The same patients also had metastasis and multiple tumors detected on DOTANOC PET scan. It was concluded that measuring superoxide anions in excised tumor tissue can be used to estimate malignant potential of CBT and can identify patients who truly require DOTANOC PET scan; without affecting the treatment, as it is an expensive investigation involving ionizing radiation and may not be available in all centres.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-03623-6.

Paraganglioma of the Head and Neck: A Review

OBJECTIVE

To review the epidemiology, presentation, diagnosis, and management of head and neck paragangliomas.

METHODS

A literature review of english language papers with focus on most current literature.

RESULTS

Paragangliomas (PGLs) are a group of neuroendocrine tumors that arise in the parasympathetic or sympathetic ganglia. Head and neck PGLs (HNPGLs) comprise 65% to 70% of all PGLs and account for 0.6% of all head and neck cancers. The majority of HNPGLs are benign, and 6% to 19% of all HNPGLs develop metastasis outside the tumor site and significantly compromise survival. PGLs can have a familial etiology with germline sequence variations in different susceptibility genes, with the gene encoding succinate dehydrogenase being the most common sequence variation, or they can arise from somatic sequence variations or fusion genes. Workup includes biochemical testing to rule out secretory components, although it is rare in HNPGLs. In addition, imaging modalities, such as computed tomography and magnetic resonance imaging, help in monitoring in surgical planning. Functional imaging with DOTATATE-positron emission tomography, 18F-fluorodeoxyglucose, or 18F-fluorohydroxyphenylalanine may be necessary to rule out sites of metastases. The management of HNPGLs is complex depending on pathology, location, and aggressiveness of the tumor. Treatment ranges from observation to resection to systemic treatment. Similarly, the prognosis ranges from a normal life expectancy to a 5-year survival of 11.8% in patients with distant metastasis.

CONCLUSION

Our review is a comprehensive summary of the incidence, mortality, pathogenesis, presentation, workup and management of HNPGLs.

Clinicopathological characteristics of patients with carotid body tumor with cervical lymph node metastasis: A retrospective study of 10 cases and review of the literature

Carotid body tumor (CBT), also known as carotid body chemoreceptor tumor or nonchromaffin paraganglioma, originates from the chemoreceptor behind the common carotid artery bifurcation in the carotid sheath. Most CBTs are benign. Malignant CBT (MCBT) is extremely rare, and cervical lymph node metastasis (CLNM) is usually regarded as a manifestation of malignant behavior. The association between CLNM, pathological features of the primary lesion, clinical manifestations, and prognosis deserves further investigation. The clinical materials of 133 patients with CBT who underwent total resection of the primary tumor and concomitant selective neck dissection (SND) from February 2002 to June 2018 in a single center were reviewed. Postoperative histopathology confirmed CLNM in 10 cases (10/133); clinical manifestations, pathological and imaging characteristics, and treatment outcome data were reviewed and analyzed. The average patient age was 50.5 years, with a female sex tendency (7/10). The mean and median follow-up periods of all cases were 6.9 years and 7 years, respectively. Nine patients (9/10) survived; one patient died of multiple systemic metastases 10 months after surgery when the tumor metastasized to the bilateral breast and other organs in an orderly manner. None of the patients had local recurrence, but postoperative residual lesions were detected by computer-aided 3-dimensional (3D) visualization computerized tomography in one (1/10). Most CBT cases with CLNM displayed adverse features, especially in patients without distant metastases. Immunohistochemically, the patient with distant metastases was negative for S-100, synaptophysin (Syn), and succinate dehydrogenase B (SDHB) expression. Most patients with CBT with CLNM have a good prognosis. Breast metastasis is an exceedingly rare manifestation of MCBT. Despite some association between clinical biological and histological malignancies in CBT with CLNM, the association seems to be vague in cases involving distant metastasis. The combination of certain immunohistochemical indicators (S-100, Syn, and SDHB) might be valuable for predicting the occurrence of distant metastasis. Computer-aided 3D visualization technology might be helpful for the diagnosis and postoperative follow-up of MCBT. Simultaneous SND can remove potentially metastatic lymph nodes and facilitate diagnosis and treatment.

Local Tumor Behavior Associated With Survival Among Patients With Paraganglioma of the Head and Neck

Objective

The purpose of this study was to evaluate the utility of ICD-O-3–classified local tumor behavior as a prognosticator of head and neck paraganglioma (HNP) outcomes.

Study Design

Retrospective cohort study.

Setting

National Cancer Database between 2004 and 2016.

Methods

This study included patients aged ≥18 years who were diagnosed with HNP. Clinical outcomes and clinicopathologic features were compared with regard to local tumor behavior.

Results

Our study included 525 patients, of which the majority had HNP classified as locally invasive (45.9%) or borderline (37.9%). The most common anatomic sites involved were the carotid body (33.7%), intracranial regions (29.0%), or cranial nerves (25.5%). Carotid body tumors were exclusively locally invasive, whereas intracranial and cranial nerve HNP were overwhelmingly benign or borderline (94% and 91%, respectively). One-fourth of patients underwent pathologic analysis of regional lymph nodes, of which the majority were positive for metastasis (80.6%). Metastasis to distant organs was twice as common in patients with locally invasive tumors vs benign (15% vs 7.1). For benign disease, surgery with radiotherapy (adjusted hazard ratio [aHR], 40.45; P = .006) and active surveillance (aHR, 24.23; P = .008) were associated with worse survival when compared with surgery alone. For locally invasive tumors, greater age (aHR, 1.07; P < .0001) and positive surgical margins (aHR, 4.13; P = .010) were predictors of worse survival, while combined surgery and radiotherapy were predictors of improved survival vs surgery alone (aHR, 0.31; P = .027).

Conclusion

While criteria for tumor behavior could not be defined, our results suggest that such a classification system could be used to enhance HNP risk stratification and guide clinical management decisions.

Head/neck paragangliomas: focus on tumor location, mutational status and plasma methoxytyramine

Head and neck paragangliomas (HNPGLs) are tumors of parasympathetic origin that occur at variable locations and are often secondary to germline mutations in succinate dehydrogenase (SDH) subunit genes. Occasionally, these tumors produce catecholamines. Here, we assessed whether different locations of HNPGLs relate to the presence of SDHx mutations, catecholamine production and other presentations. In this multicenter study, we collected clinical and biochemical data from 244 patients with HNPGLs and 71 patients without HNPGLs. We clarified that jugulotympanic HNPGLs have distinct features. In particular, 88% of jugulotympanic HNPGLs arose in women, among whom only 24% occurred due to SDHx mutations compared to 55% in men. Jugulotympanic HNPGLs were also rarely bilateral, were of a smaller size and were less often metastatic compared to carotid body and vagal HNPGLs. Furthermore, we showed that plasma concentrations of methoxytyramine (MTY) were higher (P < 0.0001) in patients with HNPGL than without HNPGL, whereas plasma normetanephrine did not differ. Only 3.7% of patients showed strong increases in plasma normetanephrine. Plasma MTY was positively related to tumor size but did not relate to the presence of SDHx mutations or tumor location. Our findings confirm that increases in plasma MTY represent the main catecholamine-related biochemical feature of patients with HNPGLs. We expect that more sensitive analytical methods will make biochemical testing of HNPGLs more practical in the future and enable more than the current 30% of patients to be identified with dopamine-producing HNPGLs. The sex-dependent differences in the development of HNPGLs may have relevance to the diagnosis, management and outcomes of these tumors.

Tumour to tumour metastasis: case of a carotid body paraganglioma metastatic to a hepatocellular adenoma

Tumour to tumour metastases are uncommon, and we report a case of carotid body paraganglioma metastatic to a hepatocellular adenoma. A 54-year-old man presented after a CT chest for chronic cough that incidentally identified two liver lesions in segment 3 and caudate. The imaging findings were suspicious for atypical haemangiomas versus hepatocellular adenoma. The segment 3 lesion was biopsied, demonstrating beta-catenin activated hepatocellular adenoma. He underwent partial hepatectomy with pathology showing the beta-catenin activated hepatocellular adenoma contained a central area of paraganglioma. On closer review, the patient revealed a carotid body paraganglioma with lymph node metastases requiring resection 24 years earlier. He subsequently underwent left hepatectomy including the resection bed and caudate, which confirmed the caudate lesion as metastatic paraganglioma. This case demonstrates how paraganglioma can metastasise to liver decades after initial resection and provide insight into the diagnostic workup for hepatocellular adenoma with neuroendocrine features.

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.

[Modern conceptions on neck paragangliomas]

Neck paragangliomas are orphan diseases with incidence 1:30 000-1:100 000. Life expectancy is poor in patients with distant metastasis (5-year overall survival 11.8%), whereas 5-year overall survival in patients with regional metastasis is 76.8-82.4%. Meanwhile, there is still no any reliable tool for prediction of malignant potential of paraganglioma. Above-mentioned data indicate an importance of early diagnosis and timely treatment of neck paragangliomas. Total resection of tumor in ablastic conditions is a gold standard of treatment. However, surgery is associated with a high risk of neurovascular complications and requires multidisciplinary approach. Nevertheless, new knowledge dedicated to different aspects of pathogenesis of neck paraganglioma, diagnosis and treatment arise every year. This review is devoted to modern data on neck paragangliomas.

Potential Biomarkers of Metastasizing Paragangliomas and Pheochromocytomas

Paragangliomas and pheochromocytomas (PPGLs) are rare neuroendocrine tumors originating from paraganglionic tissue in many sites of the body. Most PPGLs are characterized by nonaggressive behavior but all of them have the potential to metastasize. PPGLs represent a great diagnostic dilemma as it is difficult to recognize tumors that are likely to be metastasizing; criteria of malignancy can be found both in benign and metastatic forms. This review aims to analyze the current knowledge of the nature of metastasizing PPGLs paying particular attention to head and neck paragangliomas (HNPGLs). Potential predictors of the malignancy risk for PPGLs were summarized and discussed. These data may also help in the development of diagnostic and prognostic strategies, as well as in the identification of novel potential therapeutic targets for patients with PPGLs.

Cervical paragangliomas: experience of 114 cases in 14 years

Introduction and objective

To report a single center experience with carotid body paraganglioma cases that were treated by the same surgeon in a city with high prevalence of paragangliomas due to high altitude.

Methods

We retrospectively investigated the demographic, clinicopathological and radiological data of 104 patients diagnosed with cervical paragangliomas between 2003 and 2017. The patients were classified according to the Shamblin classification.

Results

In this study a total of 104 patients (33 male and 71 female, with a mean age of 54.6 ± 13 years) diagnosed with cervical paragangliomas located on carotid bifurcation between 2003 and 2017 were included. Among those patients, 10 presented with bilateral tumors and in total, 114 paragangliomas were managed in this period. The mean diameter of the tumors was 5.12 ± 1.45 cm. Malignant tumor was determined in only one (0.9%) patient. All patients were operated. In 12 patients with the tumor diameter larger than 5 cm, preoperative coil embolization was achieved. In 14 patients, preoperative angiographic embolization was employed and in 4 patients intraoperative sclerosing agent injections were performed. Facial paralysis was observed in 2 patients and dysphagia was present in 1 patient, Horner syndrome was seen in 1 patient and hoarseness was reported in 7 patients after operation. All those complications improved during follow-up. Mortality was not reported in any cases.

Conclusion

Surgery is the definitive treatment for patients with cervical paragangliomas. Although, it may be difficult in patients with the advanced Shamblin types, in experienced hands, complication rates are very low.

Longest survival by the combination of radiation-therapy and resection in patient with metastatic spinal paragangliomas from primary-neck lesion with succinate dehydrogenase subunit B (SDHB) mutation

Metastatic paraganglioma (MPG) of the spine is a rare condition, with no established management. Herein, we report the longest survival case of a primary neck tumor that caused spinal MPG with a succinate dehydrogenase subunit B (SDHB) mutation (c.470delT, p.L157X) which could have promoted its malignancy. This male patient initially presented with a left neck PG which was diagnosed by a biopsy when he was 54 years-old. Simultaneously performed additional examinations revealed the spinal metastatic tumors on the T5-7 vertebrae and L3 vertebra-sacrum. These primary neck and metastatic spinal tumors' growths were once suppressed under the radiation therapy. Nineteen years later, he developed acute progressive paraparesis due to a mass located at the T2-3 level, tightly compressing the spinal cord, and protruding into the left thoracic cavity. We resected the maximum possible area of tumor in the spinal canal, confirmed MPG by histological examination, and then, we administered radiation therapy of 40 Gy in 20 fractions. Eventually, the patient was able to walk unaided with no evidential tumor recurrence for 3 years after treatment. Generally, clinical feature of MPG with SDHB mutation from abdominal lesion is thought to be poor prognosis. However, our case suggests the possibility of long-term control of spinal MPG with the adequate combination of radiation therapy and resection if metastatic lesions from primary-neck lesion with an SDHB mutation are remained to spine.

Metastatic Paraganglioma of the Spine With SDHB Mutation: Case Report and Review of the Literature

BACKGROUND

Paragangliomas (PGLs) are rare neuroendocrine tumors that can arise from any autonomic ganglion of the body. Most PGLs do not metastasize. Here, we present a rare case of metastatic PGL of the spine in a patient with a germline pathogenic succinate dehydrogenase subunit B (SDHB) mutation.

METHODS

In addition to a case report we provide a literature review of metastatic spinal PGL to highlight the importance of genetic testing and long-term surveillance of these patients.

RESULTS

A 45-year-old woman with history of spinal nerve root PGL, 17 years prior, presented with back pain of several months' duration. Imaging revealed multilevel lytic lesions throughout the cervical, thoracic, and lumbar spine as well as involvement of the right mandibular condyle and clavicle. Percutaneous biopsy of the L1 spinal lesion confirmed metastatic PGL and the patient underwent posterior tumor resection and instrumented fusion of T7-T11. Postoperatively the patient was found to have a pathogenic SDHB deletion.

CONCLUSIONS

Patients with SDHx mutation, particularly SDHB, have increased risk of developing metastatic PGLs. Consequently, these individuals require long-term surveillance given the risk for developing new tumors or disease recurrence, even years to decades after primary tumor resection. Surgical management of spinal metastatic PGL involves correcting spinal instability, minimizing tumor burden, and alleviating epidural cord compression. In patients with metastatic PGL of the spine, genetic testing should be considered.

Differential Diagnosis and Treatment Outcomes of Tumors at the Carotid Bifurcation

Purpose

Primary tumor at the carotid bifurcation is uncommon, which includes paraganglioma, schwannoma, and lymphoma. Due to their rarity, characteristics of these tumors and problems related to their surgical treatment have not been well known. We tried to elucidate different clinical characteristics and surgical complications of these tumors.

Materials and Methods

We retrospectively reviewed 21 patients with carotid bifurcation tumor from the Vascular Surgery division of a Korean tertiary institution from 1995 to 2018. We investigated patients' demographics and clinical features, image characteristics, treatment details, and surgical outcomes.

Results

During the period from January 1995 to January 2018, we experienced surgical resections of 21 carotid bifurcation tumors which included 16 (76.2%) paragangliomas and 5 (23.8%) schwannomas. The most common clinical feature was a non-tender cervical mass. According to Shamblin classification, paragangliomas were classified into class II in 68.8% and class III in 25.0%. On the preoperative computed tomography images, all the paragangliomas showed characteristic splaying of the carotid bifurcation and hypervascularity of the tumors. On the contrary, all the schwannomas showed hypovascularity and splaying sign in 60%. Surgical complications related to cervical nerve injury developed in 50% and 60% of patients with Shamblin class III paraganglioma and schwannoma, respectively. During the mean follow-up period of 25 months (range, 1 to 163 months), distant metastases developed in 2 (12.5%) of paraganglioma patients.

Conclusion

Neurologic complications were more common after surgical resection of Shamblin class III paraganglioma and schwannoma. For patients with paraganglioma, postoperative periodic follow-up examination is advised to detect distant metastasis.

Recurrence and Progression of Head and Neck Paragangliomas after Treatment

OBJECTIVE

To characterize the recurrence of head and neck paragangliomas and the factors associated with disease progression after treatment.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary care center.

SUBJECTS AND METHODS

In total, 173 adults with 189 paragangliomas (41.3% carotid body, 29.1% glomus jugulare, 19.0% glomus tympanicum, and 10.6% glomus vagale) treated between 1990 and 2010 were evaluated to determine the incidence and risk of recurrence using Cox proportional hazards.

RESULTS

The mean (SD) follow-up duration was 8.6 (9.1) years. The incidence was 2.92 recurrences per 100 person-years. The rate of recurrence was 8.2% (95% confidence interval [CI], 3.7-12.7) after 4 years and 17.1% (95% CI, 10.2-24.0) after 10 years. Glomus jugulare tumors were more likely to recur (hazard ratio [HR], 3.69; 95% CI, 1.70-8.01; P < .001) while carotid body tumors were less likely (HR, 0.44; 95% CI, 0.21-0.97; P = .041). Radiation had a lower risk of recurrence or progression compared to surgical excision (HR, 0.30; 95% CI, 0.10-.94; P = .040). Recurrence was associated with right-sided paragangliomas (HR, 3.60; 95% CI, 1.63-7.75; P = .001). The median time to recurrence was 18.4 years. Six (3.2%) patients developed metastasis, which was more common with local recurrence (9.5% vs 1.4%, P = .015).

CONCLUSIONS

Recurrence is more common with glomus jugulare tumors and less common with carotid body tumors. Radiation may have a lower risk of recurrence or progression than surgery for some paraganglioma types. Metastasis is rare but more likely with recurrent disease. Surveillance neck imaging is recommended every several years for decades after treatment.

Is Regional Lymph Node Metastasis of Head and Neck Paraganglioma a Sign of Aggressive Clinical Behavior: A Clinical/Pathologic Review

BACKGROUND

Head and neck paraganglioma is a rare neoplasm of the paraganglia. It accounts for <1% of all head and neck tumors. It usually has benign clinical course; however, malignant paraganglioma can only be diagnosed by showing metastatic disease. We undertook a retrospective study to assess the clinical significance of regional lymph nodes metastases in head and neck paragangliomas.

DESIGN

From 1993 to 2016, primary head and neck paragangliomas are identified. The patient clinical and histopathologic materials were reviewed.

RESULTS

Sixty-five specimens from 62 patients (3 patients with more than 1 specimens) with head and neck paragangliomas were recorded (49 female and 13 males) with mean age of 54 (24-78 years). The locations of the tumors were as follows: carotid body: 30, glomus tympanicum: 11, glomus jugulare: 14, parapharyngeal space: 3, and 1 case each of larynx, skull base, paraglottic area, infratemporal fossa, mastoid, cerebellopontine (CP) angle, and pyriform sinus. On histopathology, we found 5 cases of sclerosing variant. Thirty-two (52%) of the 62 patients had regional lymph node biopsy. Four (12%) of the 32 show metastatic paraganglioma (3 females and 1 male with mean age = 35). Two of the 5 cases of sclerosing variant had positive lymph nodes. No evidence of local recurrence or distant metastasis in the patients with positive lymph nodes with a 6 to 11 years follow-up. One of the 28 patients with negative lymph nodes developed metastatic disease to lumbar spine in 5 years.

CONCLUSION

Metastatic paraganglioma to regional lymph nodes may have indolent clinical behavior, with disease-free survival of up to 11 years. The incidence of metastatic disease in lymph nodes was 4 (12%) of 32. Forty percent (2/5) of the cases with sclerosing variant of paraganglioma had lymph node metastases indicating that this tumor may have a more aggressive histological behavior.

Pathology and genetics of phaeochromocytoma and paraganglioma

Phaeochromocytoma and paraganglioma (PHEO/PGL) are rare tumours with an estimated annual incidence of 3 per million. Advances in molecular understanding have led to the recognition that at least 30-40% arise in the setting of hereditary disease. Germline mutations in the succinate dehydrogenase genes SDHA, SDHB, SDHC, SDHD and SDHAF2 are the most prevalent of the more than 19 hereditary genetic abnormalities which have been reported. It is therefore recommended that, depending on local resources and availability, at least some degree of genetic testing should be offered to all PHEO/PGL patients, including those with clinically sporadic disease. It is now accepted that that all PHEO/PGL have some metastatic potential; therefore, concepts of benign and malignant PHEO/PGL have no meaning and have been replaced by a risk stratification approach. Although there is broad acceptance that certain features, including high proliferative activity, invasive growth, increased cellularity, large tumour nests and comedonecrosis, are associated with an increased risk of metastasis, it remains difficult to predict the clinical behaviour of individual tumours and no single risk stratification scheme is endorsed or in widespread use. In this review, we provide an update on advances in the pathology and genetics of PHEO/PGL with an emphasis on the changes introduced in the WHO 2017 classification of endocrine neoplasia relevant to practising surgical pathologists.

Clinical progression and metachronous paragangliomas in a large cohort of SDHD germline variant carriers

Although it is well established that paternally transmitted germline variants in SDHD are associated with multifocal paragangliomas and lifelong follow-up is generally advised, the risk of metachronous lesions is presently unknown. In a large Dutch cohort of SDHD variant carriers, we studied the development of new paragangliomas, and the evolution of symptoms and cranial nerve impairment. Recurrent event analysis and the Kaplan-Meier product limit estimator were used to study the risk of new lesions. The relation between several predictors and development of new symptoms was assessed using logistic regression. Of the 222 SDHD variant carriers included, 65% presented with symptoms and 11% with cranial nerve dysfunction. Over a median period of 8 years, 42% reported new symptoms, and new cranial nerve impairment was observed in 11% of subjects. The estimated fraction of subjects that developed new HNPGL increased to 73% (95% CI: 52-85%) after 22 years of follow-up. Males were more likely to develop new HNPGL compared to females (HR: 1.63, 95% CI: 1.10-2.40), as were subjects that presented with symptoms, compared to subjects that were asymptomatic at baseline (HR: 1.61, 95% CI: 1.01-2.55). In addition, the risk of new lesions decreased with number of HNPGL present at first diagnosis (HR: 0.68 and 95% CI: 0.56-0.82). Carriers of a paternally inherited SDHD variant face a considerable risk for new HNPGL. In addition, nearly 50% of subjects reported new symptoms. However, new cranial nerve deficits were observed in only 11%, which is less than reported in surgical series. These risks should be taken into account when considering treatment strategies and counseling.

SDHD promoter mutations are rare events in cutaneous melanomas but SDHD protein expression is downregulated in advanced cutaneous melanoma

BACKGROUND

SDHD promoter mutations were reported in 4-10% of cutaneous melanomas. The advanced clinico-pathological and patient survival association with SDHD mutation and/or expression in cutaneous melanoma remains controversial.

OBJECTIVES

To evaluate the presence of SDHD promoter mutations and SDHD protein expression in a melanoma series and its possible association with prognosis and survival of the patients.

METHODS

We assessed SDHD promoter status in cutaneous melanomas (CM), ocular melanomas (OM) and melanoma cell lines, and the expression of SDHD protein by immunohistochemistry in CM and OM, and by western blot in melanoma cell lines. We explored the putative association between SDHD protein expression and clinico-pathological and prognostic parameters of melanoma.

RESULTS

We detected 2% of SDHD promoter mutations in CM, but none in OM and cell lines. SDHD protein expression was present in all CM, in OM and in all CM and OM derived cell lines analysed. A significant association between lower SDHD mean protein expression and presence of ulceration and higher pT stage was found.

CONCLUSIONS

SDHD promoter mutation seems to be a rare event in CM but SDHD lower expression might associate with worst prognostic features in CM.

Familial Cancers of Head and Neck Region

Cancers that occur in families more often than would be expected by chance are termed as familial cancers. They occur due to an inherited genetic mutation and account for 5%-10% of all cancers. This review article presents some of the common Familial Cancer Syndromes (FCS) such as MEN 2B, hyperparathyroidism-jaw tumour syndrome, familial oral squamous cell carcinoma, melanoma, nasopharyngeal carcinoma, paraganglioma, neurofibroma and other syndromes associated with head and neck region.

Polymyalgia rheumatica and vagal paraganglioma

INTRODUCTION

Vagal paraganglioma are rare tumors that are mostly asymptomatic. We report a case of vagal paraganglioma associated with paraneoplastic polymyalgia rheumatica and review the literature on benign paragangliomas of the head and neck associated with paraneoplastic syndrome.

CASE REPORT

A 53-year-old man presented with atypical polymyalgia rheumatica. MRI revealed a tumor that was then surgically excised. Histological examination confirmed the diagnosis of benign vagal paraganglioma. Rapid, complete and permanent resolution of all rheumatological symptoms were observed postoperatively, confirming the diagnosis of paraneoplastic polymyalgia rheumatica.

CONCLUSION

Paraganglioma of the neck associated with paraneoplastic syndrome remains exceptional. A predisposing gene mutation must be systematically investigated. Long-term surveillance must be ensured due to the risk of local recurrence, second tumors or metastasis.

Molecular markers of paragangliomas/pheochromocytomas

Paragangliomas/pheochromocytomas comprise rare tumors that arise from the extra-adrenal paraganglia, with an incidence of about 2 to 8 per million people each year. Approximately 40% of cases are due to genetic mutations in at least one out of more than 30 causative genes. About 25-30% of pheochromocytomas/paragangliomas develop under the conditions of a hereditary tumor syndrome a third of which are caused by mutations in the VHL gene. Together, the gene mutations in this disorder have implicated multiple processes including signaling pathways, translation initiation, hypoxia regulation, protein synthesis, differentiation, survival, proliferation, and cell growth. The present review contemplates the mutations associated with the development of pheochromocytomas/paragangliomas and their potential to serve as specific markers of these tumors and their progression. These data will improve our understanding of the pathogenesis of these tumors and likely reveal certain features that may be useful for early diagnostics, malignancy prognostics, and the determination of new targets for disease therapeutics.

Imaging characteristics of nodal metastases in paraganglioma, ameloblastoma and olfactory neuroblastoma: case reports and literature review

Paraganglioma, ameloblastoma and olfactory neuroblastoma are uncommon primary head and neck tumours. When nodal metastases from these tumours occur, they may present later than and with different imaging characteristics compared with squamous cell carcinoma (SCC), demonstrating appearances similar to the primary tumour type rather than features typical of metastatic nodal SCC. We present three cases in which imaging characteristics of nodal metastases in paraganglioma, ameloblastoma and olfactory neuroblastoma mimicked the primary tumour and discuss their implications for clinicoradiological follow-up.

Anatomical Considerations on Surgical Anatomy of the Carotid Bifurcation

Surgical anatomy of carotid bifurcation is of unique importance for numerous medical specialties. Despite extensive research, many aspects such as precise height of carotid bifurcation, micrometric values of carotid arteries and their branches as their diameter, length, and degree of tortuosity, and variations of proximal external carotid artery branches are undetermined. Furthermore carotid bifurcation is involved in many pathologic processes, atheromatous disease being the commonest. Carotid atheromatous disease is a major predisposing factor for disabling and possibly fatal strokes with geometry of carotid bifurcation playing an important role in its natural history. Consequently detailed knowledge of various anatomic parameters is of paramount importance not only for understanding of the disease but also for design of surgical treatment, especially selection between carotid endarterectomy and carotid stenting. Carotid bifurcation paragangliomas constitute unique tumors with diagnostic accuracy, treatment design, and success of operative intervention dependent on precise knowledge of anatomy. Considering those, it becomes clear that selection and application of proper surgical therapy should consider anatomical details. Further research might ameliorate available treatment options or even lead to innovative ones.

What happens in vagus: a case of recurrent paraganglioma with malignant transformation and an updated treatment algorithm†

Paragangliomas (PGLs) are rare, extra-adrenal tumors, originating from neural crest cells and can occur anywhere from the skull base to the pelvic floor. Although these tumors are often benign, a fraction of malignant cases exist. Few isolated cases of malignant head and neck PGL are reported in the literature. Treatment algorithms rely heavily on retrospective case studies and institutional experience. We report an unusual case of an extensive, hereditary PGL, with invasive characteristics, that was refractory to radiation therapy. An operative approach was selected for recurrent disease in the setting of critical neurovascular structure compromise. Six months postoperatively, the patient was recovering as expected and had no evidence of recurrent disease. We propose a modified treatment algorithm based on an updated literature review that encompasses the spectrum of PGL, from benign and asymptomatic to invasive and malignant disease.