Malignant head and neck paragangliomas: treatment efficacy and prognostic indicators

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.

Epidemiology and survival of patients with malignant carotid body tumors in the SEER database

OBJECTIVE

The objective of this study was to investigate population-based epidemiology, survival outcomes, and prognostic factors of malignant carotid body tumors (CBTs).

METHODS

Patients with malignant CBTs who were diagnosed between 1975 and 2018 were screened from nine registries of the Surveillance, Epidemiology, and End Results (SEER) database. Cases that were coded as "carotid body tumor, malignant" or malignant tumors with the primary site recorded as "carotid body" were screened for inclusion in the study. The incidence of malignant CBT was calculated with SEER∗Stat software. Survival outcomes were analyzed using the Kaplan-Meier method and log-rank tests.

RESULTS

A total of 72 patients with malignant CBT were screened for inclusion in the study, including 41 females (56.9%) and 31 males (43.1%). Based on the SEER program data, the incidence of malignant CBT was found to fluctuate between 0 to 0.02 cases per 100,000 people per year, with a slow but noticeable uptick after 1990. The most commonly affected populations included women and patients between the ages of 35 and 44, which accounted for 59.9% and 27.8% of patients in the study, respectively. During a median follow-up of 82 months, four patients were lost to follow-up, and 28 deaths were identified. Of those, 20 were considered disease-specific deaths. Further analysis found that the 5-year and 10-year overall survival rates were 78.9% and 67.8%, respectively, whereas the 5-year and 10-year disease-specific survival rates were 84.5% and 75.2%, respectively. The Kaplan-Meier method and log-rank tests indicated that age <50 years, sex, race, tumor number, and surgical treatment were unrelated to both overall survival and disease-specific survival.

CONCLUSIONS

A retrospective review of the SEER database found that the incidence of malignant CBT was extremely rare and prone to fluctuation, but that it slowly trended upward over time. Malignant CBT was found to more likely affect females, and it could be diagnosed at any age. The overall prognosis for malignant CBT appeared to be good, with acceptable 5-year and 10-year survival rates. Due to a number of factors complicating malignant CBT surgery, surgical treatment should be considered with caution.

A Predictive Nomogram for Early Death in Pheochromocytoma and Paraganglioma

Background

Pheochromocytoma (PHEO) and paraganglioma (PGL) are relatively rare neuroendocrine tumors. The factors affecting patients with early death remain poorly defined. We aimed to study the demographic and clinicopathologic pattern and to develop and validate a prediction model for PHEO/PGL patients with early death.

Methods

Data of 800 participants were collected from the Surveillance Epidemiology and End Results (SEER) database as a construction cohort, while data of 340 participants were selected as a validation cohort. Risk factors considered included the year of diagnosis, age at diagnosis, gender, marital status, race, insurance status, tumor type, primary location, laterality, the presence of distant metastasis. Univariate and multivariate logistic regressions were performed to determine the risk factors. R software was used to generate the nomogram. Calibration ability, discrimination ability, and decision curve analysis were analyzed in both construction and validation cohorts.

Results

PHEO and PGL patients accounted for 54.3% (N=434) and 45.7% (N=366), respectively. More than half of tumors (N=401, 50.1%) occurred in the adrenal gland, while 16.9% (N=135) were in aortic/carotid bodies. For the entire cohort, the median overall survival (OS) was 116.0 (95% CI: 101.5-130.5) months. The multivariate analysis revealed that older age (versus age younger than 31; age between 31 and 60: OR=2.03, 95% CI: 1.03-4.03, P=0.042; age older than 60: OR=5.46, 95% CI: 2.68-11.12, P&lt;0.001), female gender (versus male gender; OR=0.59, 95% CI: 0.41-0.87, P=0.007), tumor located in aortic/carotid bodies (versus tumor located in adrenal gland; OR=0.49, 95% CI: 0.27-0.87, P=0.015) and the presence of distant metastasis (versus without distant metastasis; OR=4.80, 95% CI: 3.18-7.23, P&lt;0.001) were independent risk factors of early death. The predictive nomogram included variables: age at diagnosis, gender, primary tumor location, and distant metastasis. The model had satisfactory discrimination and calibration performance: Harrell’s C statistics of the prediction model were 0.733 in the construction cohort and 0.716 in the validation cohort. The calibration analysis showed acceptable coherence between predicted probabilities and observed probabilities.

Conclusions

We developed and validated a predictive nomogram utilizing data from the SEER database with satisfactory discrimination and calibration capability which can be used for early death prediction for PHEO/PGL patients.

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.

Head and neck paragangliomas: Ten years of experience in a third health center. A cohort study

Head and neck paragangliomas are rare vascular tumors derived from the paraganglionic system, located at the carotid body, jugular vein, tympanic cavity and vagal nerve.

From 2010 to 2020, a cohort of 26 patients divided in two groups, 15 with cervical paragangliomas and 11 with temporal bone paragangliomas, was reviewed by analysing the medical history, the epidemiological and clinical parameters, the imaging results and classification, the modality of treatment and outcome.

Cervical paragangliomas present as firm and pulsatile mass with the characteristic aspect of “salt and pepper” on MRI T1 weighted sequences. The most common type on Shamblin classification was the type II. Total surgical resection was performed in 93,33% of cases. The sensitivity of MRI in the diagnosis of vagal paragangliomas was up to 75%, with a specificity of 90,91% and the correlation of the MRI results and the findings of surgical exploration is significant with p ⩽ 0.02.

Temporal bone paragangliomas appear as pulsatile mass behind the tympanic membrane, causing variable hearing loss in 90,90% of the cases. The facial nerve is the most frequently affected cranial nerve, in 36,36% of the cases. The main type according to FISH classification is the type B. Embolization was performed in all type C tumors. Surgery was the first line treatment while the inoperable patients were considered for radiotherapy.

The aim of this study is to report the main clinical features of head and neck paragangliomas, the imaging tools and findings evaluating their sensitivity and specificity and the treatment protocol and outcome.

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Head and neck paragangliomas are rare, usually benign hypervascular tumors, characterized by slow growth over time.

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Typical clinical manifestations and imaging evaluation should be considered together to establish the treatment protocol.

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MRI is efficient to detect vagal paragangliomas.

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Surgery provides excellent control of the tumor while radiation therapy is considered for surgery contraindication.

The North American Neuroendocrine Tumor Society Consensus Guidelines for Surveillance and Management of Metastatic and/or Unresectable Pheochromocytoma and Paraganglioma

ABSTRACT

This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the medical management and surveillance of metastatic and unresectable pheochromocytoma and paraganglioma held on October 2 and 3, 2019. The panelists consisted of endocrinologists, medical oncologists, surgeons, radiologists/nuclear medicine physicians, nephrologists, pathologists, and radiation oncologists. The panelists performed a literature review on a series of questions regarding the medical management of metastatic and unresectable pheochromocytoma and paraganglioma as well as questions regarding surveillance after resection. The panelists voted on controversial topics, and final recommendations were sent to all panel members for final approval.

Carcinoma del glomus carotideo. Serie de casos

Introducción. El carcinoma del glomus carotideo es infrecuente y se presenta en el 6 % de los paragangliomas carotideos. Suele haber dificultad en su diagnóstico preoperatorio y no se diferencia fácilmente de su contraparte benigna, lo que puede conllevar a complicaciones quirúrgicas. Este trabajo describe la experiencia en su abordaje clínico y quirúrgico en una serie de casos, además de una revisión de la literatura profundizando en su diagnóstico, abordaje terapéutico, sobrevida y mortalidad. Métodos. De los pacientes operados por glomus carotideos durante un periodo de 20 años, se identificaron aquellos llevados a cirugía por carcinoma. Se realizó una búsqueda bibliográfica extensa en PubMed, haciendo énfasis en diagnóstico y tratamiento. Resultados. De un total de 139 pacientes sometidos a cirugía de resección de tumor del cuerpo carotideo, tres pacientes (2,2 %) presentaron carcinoma. Dos tenían metástasis cervicales y uno metástasis hepáticas. Uno presentaba glomus bilateral asociado a trastorno genético de origen familiar. Se realizó cirugía y adyuvancia en todos los casos. Discusión. El diagnóstico diferencial preoperatorio entre glomus benigno y maligno es difícil, por lo cual deben buscarse hallazgos clínicos o factores de riesgo que puedan sugerir malignidad. Las imágenes pocas veces muestran características claras de invasión vascular. Siempre que sea posible, en el tratamiento del cáncer del glomus carotideo, debe realizarse resección quirúrgica, acompañada de un vaciamiento funcional de cuello, dejando la radioterapia, la quimioterapia y la hormonoterapia como terapias adyuvantes.

Surgical outcomes and factors associated with malignancy in carotid body tumors

OBJECTIVE

To compare the surgical outcomes of benign and malignant carotid body tumor (CBT), and to evaluate the associated factors of malignant CBT.

METHODS

Patients who underwent surgical resection of CBT from 2005 to 2018 in a tertiary center were reviewed retrospectively. The common study follow-up end date was December 31, 2019. The tumor size was measured as the maximum transverse diameter on computed tomography scan. Surgical outcomes of benign and malignant CBT were compared. Associated factors of malignancy were analyzed by multivariate logistic analysis.

RESULTS

There were 229 patients undergoing CBT resection. Sixteen patients were diagnosed with malignant CBT. The median follow-up time was 66 months (range, 6-142 months). Basic information including age, sex, course of disease, family history, lesion side, tumor size, and Shamblin classification showed no significant differences between the benign and malignant CBT groups. Patients with malignant CBTs showed a higher rate of preoperative symptoms (31.3% vs 12.2%; P < .05). The rates of vascular reconstruction or repair (P < .01) and neurologic complications (P < .05) were significantly higher in the malignant CBT group. In addition, a significantly longer average procedural time was required for malignant CBTs (P < .05). However, the estimated blood loss and length of hospital stay showed no significant difference. Multivariate logistic regression analysis revealed that the malignant odds of CBT with bilateral lesions (P = .0042; odds ratio, 8.30; 95% confidence interval, 1.84-35.88) or CBT with preoperative symptoms (P = .0016; odds ratio, 7.59; 95% confidence interval, 2.13-27.89) were high.

CONCLUSIONS

Compared with benign CBT, malignant CBT is prone to invasive clinical behaviors, resulting in an increased possibility of vascular reconstruction or repair during the surgery as well as postoperative neurologic complications. In addition, the malignant odds of CBT with bilateral lesions or CBT with preoperative symptoms are high.

Primary tumour resection for synchronously metastatic phaeochromocytoma and paraganglioma: A population-based study

CONTEXT

Until recently, there are few effective treatment options for patients with synchronous metastatic phaeochromocytoma (PHEO) and paraganglioma (PGL). Surgical resection may improve the survival outcomes of these patients.

OBJECTIVE

To assess the role of surgical resection of the primary tumour in patients with synchronous metastatic PHEO and PGL.

DESIGN

Retrospective analysis of patients with synchronous metastatic PHEO/PGL using the Surveillance, Epidemiology, and End Results database (1988-2016).

PATIENTS

Patients with synchronous metastatic PHEO/PGL who underwent primary tumour resection.

MEASUREMENTS

Overall survival and Cox regression analyses.

RESULTS

A total of 99 patients with metastatic PHEO and 127 metastatic PGL patients were identified from the SEER database. Compared to metastatic PHEO, metastatic PGL patients had a better overall survival (5-year survival rate: 33.3% vs. 49.0%, p = .001). In metastatic PHEO patients, 53 (53.5%) patients underwent surgery for primary site. Surgically treated patients had an improved survival compared to non-surgery patients (5-year survival rate: 50.9% vs. 29.6%, p = .017). Among metastatic PGL patients, primary tumour resection was performed in 74 (58.3%) patients and had no significant effect on the survival of metastatic PGL. In sub-analyses, surgery only conferred a survival benefit in patients with primary tumours originated from aortic/carotid bodies, rather than other sites or abdominal tumours.

CONCLUSION

Our findings suggest that primary tumour resection is associated with improved survival in patients with synchronous metastatic PHEO and those with PGL diseases located in aortic/carotid bodies. In addition, PHEO and PGL should be treated as two distinct clinical entities.

Recurrent Primary Intrasellar Paraganglioma

We describe a case of an 81-year-old male presenting with bitemporal visual field defects and blurry vision in the right eye. The patient was found to have a recurrent primary paraganglioma in the sellar and suprasellar region requiring a repeat transsphenoidal endoscopic resection. Immunohistochemical examination confirmed paraganglioma with the classic zellballen appearance which stained positive for chromogranin, synaptophysin, and S-100 in the periphery. Paragangliomas (PGLs) in the sella turcica are a rare entity; only 19 cases have ever been reported in the literature. PGLs in the sellar region are often misdiagnosed or diagnosed in a delayed fashion. Earlier diagnosis of this locally aggressive tumor and meticulous debulking can prevent morbidity secondary to the tumor's compressive effects. This report highlights the effectiveness of surgical interventions in treatment of paragangliomas. More research is still needed to determine the need for adjuvant therapies such as radiation.

Characterization of Malignant Head and Neck Paragangliomas at a Single Institution Across Multiple Decades

Importance

Malignant head and neck paragangliomas (HNPGLs) are rare entities, and there are limited data regarding optimal treatment recommendations to improve clinical outcomes.

Objective

To classify succinate dehydrogenase (SDH) germline mutations associated with malignant HNPGLs, evaluate time from diagnosis to identification of malignant tumor, describe locations of metastases and the functional status of malignant HNPGLs, and determine the role of selective neck dissection at the time of initial surgical resection.

Design, Setting, and Participants

A retrospective cohort study was completed of patients diagnosed with paragangliomas on various sites on the body at an academic tertiary cancer hospital between the years 1963 and 2018. A subanalysis of HNPGLs was also completed. Data regarding diagnosis, gene and mutation, tumor characteristics and location, and treatments used were reviewed between February 2017 and March 2018.

Main Outcomes and Measures

Mutations of SDH genes associated with benign and malignant HNPGLs, treatments used, time to the discovery of malignancy, and location of metastasis.

Results

Of the 70 patients included in the study, 40 (57%) were male, and the mean (SD) age was 47 (21.1) years. Of patients with tumors isolated to the head and neck, 38 (54%) had benign HNPGLs, which were associated with mutations in the genes SDH subunit B (SDHB) (n = 18; 47%), SDH subunit C (n = 2; 5%), and SDH subunit D (n = 18; 47%). Among those with malignant HNPGLs, all but 1 patient had mutations in SDHB (n = 5; 83%); 1 patient had no mutation associated with their disease. The average age at diagnosis for malignant HNPGLs was 35 years, while benign tumors were diagnosed at an average age at 36 years. All patients with malignant disease underwent surgery. Four patients were found to have metastasis at the time of selective neck dissection. Among patients with malignant HNPGLs, 5 (83%) were treated with adjuvant radiation, and 1 (17%) was treated with adjuvant chemotherapy.

Conclusions and Relevance

Malignant HNPGLs are rare entities that are difficult to diagnose and are typically identified by the presence of regional or distant metastasis. The results of this study found the prevalence of malignant HNPGLs to be 9%. These data suggest that it is beneficial to perform a selective neck dissection at the time of tumor excision. All patients with malignant HNPGLs but 1 had SDHB mutations.

Two week wait referral criteria - heading in the right direction?

OBJECTIVES

The National Institute for Health and Care Excellence referral guidelines prompting urgent two-week referrals were updated in 2015. Additional symptoms with a lower threshold of 3 per cent positive predictive values were integrated. This study aimed to examine whether current pan-London urgent referral guidelines for suspected head and neck cancer lead to efficient and accurate referrals by assessing frequency of presenting symptoms and risk factors, and examining their correlation with positive cancer diagnoses.

METHODS

The risk factors and symptoms of 984 consecutive patients (over a six-month period in 2016) were collected retrospectively from urgent referral letters to University College London Hospital for suspected head and neck cancer.

RESULTS

Only 37 referrals (3.76 per cent) resulted in a head and neck cancer diagnosis. Four of the 23 recommended symptoms demonstrated statistically significant results. Nine of the 23 symptoms had a positive predictive value of over 3 per cent.

CONCLUSION

The findings indicate that the current referral guidelines are not effective at detecting patients with cancer. Detection rates have decreased from 10-15 per cent to 3.76 per cent. A review of the current head and neck cancer referral guidelines is recommended, along with further data collection for comparison.

Prognostic Factors of Malignant Pheochromocytoma and Paraganglioma: A Combined SEER and TCGA Databases Review

Pheochromocytoma (PCC) and paraganglioma (PGL) are rare malignancies while pathogenesis is strongly influenced by genetics. The prognostic factors of these patients remain poorly defined. We aim to study the epidemiology and survival pattern by analyzing the combination of SEER and Cancer Genome Atlas (TCGA) database. Primary outcome was overall survival (OS) and disease specific survival (DSS). Between 1973 and 2013, a total of 1014 patients with PGL or PCC were analyzed. Younger age and female were associated with better outcomes. The incidence of second primary malignancy in PGL/PCC patients was about 14.6%. This population had a significant longer DSS. Other factors, including surgical resection and origin from of aortic/carotid bodies, conferred remarkable survival advantage. In contrast, distant spread portended worse prognosis. Laterality, race, positive serum catecholamine marker did not demonstrate a significant association with OS and DSS. By analyzing TCGA database with total 184 patients were identified. Eighty out of 184 patients (43.5%) had at least one pathogenic mutation. Female had higher ratio of pathogenic mutations than male (58.7% vs. 41.3%) and NF1 mutation was associated with elderly population. SHDB mutation had higher percentage in male. Twenty-nine patients (15.8%) had 2 or more primary. ATRX was the most common oncogenic mutations in metastatic cohort. In conclusion, younger age, female sex, origin from aortic/carotid bodies, complete surgical resection, regional disease, as well as concomitant second primary malignancies were associated with better prognosis. The prognostic value of radiotherapy and oncogenomics warrants further investigation.

Radiotherapy for parapharyngeal space tumors

A wide variety of tumors, both benign and malignant, occur in the parapharyngeal space. Depending on histology and extent, treatment may include surgery and/or radiotherapy (RT). Herein we discuss the role of RT in the management of some of the more commonly encountered neoplasms, including salivary gland tumors, paragangliomas, schwannomas, and soft-tissue sarcomas.

Bilateral malignant paragangliomas in a patient: a rare case report

BACKGROUND

Paragangliomas are neuroendocrine neoplasms that arise from the extra-adrenal paraganglia of the autonomic nervous system. Approximately 3% of all paragangliomas occur in the head and neck region. Most reported cases are benign and unilateral. We present here a rare case of bilateral malignant paragangliomas.

CASE DESCRIPTION

A 28-year-old woman presented to our department with a 10-year history of bilateral neck swelling. Physical examination showed bilateral neck masses with obvious pulsation. Enhanced CT revealed two irregular solid nodules, located in the left and right carotid artery bifurcation, respectively. Carotid artery angiography showed compression of the internal and external carotid arteries by the tumors on both sides. Upon diagnosis of the bilateral carotid body tumors, preoperative embolization was performed. The left-side lesion as well as the lymph nodes were resected and a diagnosis of malignant paraganglioma with lymph node metastasis was made. Genetic studies have shown that familial paragangliomas are associated with germline mutation of succinate dehydrogenase subunits SDHD on 11q23. She was treated with 50-Gy radiotherapy, and a subsequent CT scan performed two years later showed that the right-side lesion was unchanged. She was symptom-free as of the last follow-up.

CONCLUSIONS

The rarity of bilateral malignant paragangliomas makes their management clinically challenging. The primary management of a recognized malignancy should be directed toward complete surgical removal of the primary tumor and regional lymph nodes. Postoperative radiation is beneficial in slowing the progression of residual disease.

Malignant Pheochromocytoma and Paraganglioma: 272 Patients Over 55 Years

CONTEXT

Malignant pheochromocytoma (PHEO) and paraganglioma (PGL) are rare and knowledge of the natural history is limited.

OBJECTIVE

We aimed to describe baseline characteristics and outcomes of patients with malignant PHEO and PGL (PPGL) and to identify predictors of shorter survival.

DESIGN

Retrospective review of patients with malignant PPGL evaluated from 1960 to 2016.

SETTING

Referral center.

PATIENTS

The group comprised 272 patients.

MAIN OUTCOME MEASURES

Baseline description, survival outcomes, and predictors of shorter survival were evaluated in patients with rapidly progressive (n = 29) and indolent disease (n = 188).

RESULTS

Malignant PPGL was diagnosed at a median age of 39 years (range, 7 to 83 years), with synchronous metastases in 96 (35%) patients. In 176 (65%) patients, metastases developed at a median of 5.5 years (range, 0.3 to 53.4 years) from the initial diagnosis. Median follow-up was 8.2 years (range, 0.01 to 54.1 years). Median overall and disease-specific survivals were 24.6 and 33.7 years, respectively. Shorter survival correlated with male sex (P = 0.014), older age at the time of primary tumor (P = 0.0011), synchronous metastases (P < 0.0001), larger primary tumor size (P = 0.0039), elevated dopamine (P = 0.0195), and not undergoing primary tumor resection (P < 0.0001). There was no difference in the type of primary tumor or presence of SDHB mutation.

CONCLUSIONS

The clinical course of patients with malignant PPGL is remarkably variable. Rapid disease progression is associated with male sex, older age at diagnosis, synchronous metastases, larger tumor size, elevated dopamine, and not undergoing resection of primary tumor. An individualized approach to patients with metastatic PPGL is warranted.

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

Background:

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

Method:

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

Results:

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

Conclusion:

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

Paragangliomas of the Head and Neck: An Overview from Diagnosis to Genetics

Paragangliomas (PGL) develop from the parasympathetic system in the head and neck (HN) and arise primarily in four distinct areas: Carotid body, vagal, middle ear, and larynx. Globally, the diagnosis and morphologic features are the same regardless of anatomic site, however the incidence, frequency of genetic alterations/syndromes and differential diagnosis vary. It is now recognized that nearly 40% of all HN PGLs are hereditary, including a significant subset without a known family history. Now pathologists are central to the evaluation for diagnosis and further management of patients with HNPGLs. Specifically, SDHB immunohistochemical evaluation is an excellent screening tool to detect tumors with alterations in the SDH family of genes that represent the majority of hereditary cases in HNPGL. Similarly, SDHB immunohistochemical analysis allows for screening of PGL syndrome associated tumors (gastrointestinal stromal tumor (GIST), renal cell carcinoma (RCC), and pituitary adenomas) that have now been linked by their overlapping gene alterations. Awareness of the spectrum of these syndromes, and their associated tumors, positions the pathologist to augment patient care and surveillance.

Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Paragangliomas

Updated editions of The World Health Organization Classification of Tumours Pathology & Genetics for both Head and Neck Tumours and Tumours of Endocrine Organs took place in 2016 based on consensus conferences. These editions present unification of concepts in paragangliomas and highlight expanding knowledge of their etiology. There is a major emphasis in the new bluebooks on familial/syndromic paragangliomas, representing ~40% of all head and neck paragangliomas. Ancillary use of immunohistochemical evaluation, specifically of SDHB, allows the pathologist to screen for a large subset of these potentially hereditary cases. In addition, similarly to other neuroendocrine tumors, paragangliomas are now considered to represent a continuum of risk, and are assessed in terms of risk stratification. Tumors with SDHB mutations pose the highest risk for metastasis. There is currently no validated or endorsed histologic grading system. Paragangliomas remain tumors of undetermined biologic potential and should not be termed benign.

External-beam radiation therapy for malignant paraganglioma of the head and neck

BACKGROUND

Malignant paragangliomas of the head and neck are very rare tumors of the neuroendocrine cells associated with the peripheral nervous system. There are limited data available to help guide treatment of these tumors and the role of radiation therapy (RT) is not well-defined. This article briefly reviews the pathology, clinical presentation, and treatment modalities of these tumors and reviews our institutional experience in treating this malignancy.

PATIENTS AND METHODS

From November 1993 through May 2005, 5 patients with 5 malignant paragangliomas of the jugular bulb and carotid body were treated with RT at the University of Florida to a median dose of 70 Gy at 1.8 Gy per fraction. Mean and median follow-up times are 12.8 years and 14.4 years, respectively.

RESULTS

We were able to achieve significant disease-free intervals of >10 years for 3 of 5 patients and >5 years for 4 of 5 patients. Of the 2 patients who failed treatment, 1 recurred 7.3 years after the RT salvage treatment following combination surgery and RT at another institution, and 1 experienced distant metastasis 2.8 years after treatment without obvious recurrence of local disease.

CONCLUSION

Malignant paragangliomas are a very rare entity whose main treatment modality has yet to be well established. Overall, data concerning outcomes are sparse, but particularly data on the role of RT in the treatment of these difficult tumors. We recommend doses to 70 Gy at 2 Gy per once-daily fraction as an adjuvant treatment with surgery to both remove the source of disease and provide microscopic control. Patients with incompletely resectable tumors are treated with RT alone.

Multidisciplinary management of locally advanced and widely metastatic paraganglioma in a patient with life-threatening compressive symptoms

BACKGROUND

Patients presenting with locally advanced, metastatic paraganglioma with life-threatening compressive symptoms of critical anatomic structure pose a significant management challenge.

METHODS

We present a case of a 15-year-old patient with enlarging right neck mass causing dysphagia and respiratory compromise from near complete obstruction of the oropharynx.

RESULTS

Evaluation of the patient's family history led to the identification of a mutation in the succinate dehydrogenase subunit B (SDSD) gene (G725A). Laboratory and imaging workup revealed an 8.8 × 6.6 × 4.1 cm metabolically and biochemically active right neck mass, a tumor in the left para-aortic region, and multiple bony lesions consistent with widely metastatic disease. Multidisciplinary management included preoperative clinical optimization, coil embolization, and palliative resection of the neck mass.

CONCLUSION

Although the currently available treatment options for patients with advanced metastatic paraganglioma render no survival benefit, a multidisciplinary management approach aimed at relief of tumor-related symptoms and catecholamine excess should be undertaken.