Clinical, histopathologic, and radiographic indicators of malignancy in head and neck paragangliomas

Ultrastructural features of tumor-associated mast cells in parasympathetic paragangliomas (chemodectomas) of the neck

The mechanisms of the pathogenesis of neck paraganglioma (PGL) and the possible role of mast cells (MCs) in its development and metastasis are still poorly understood. We analyzed MCs' morphologic characterization, activation, and the properties of their cytoplasmic/released granules in PGLs, using light and transmission electron microscopy. Paragangliomas showed a large tumor-associated MC population both in the connective tissue layers of the tumor and between the tumor cells. Notably, MCs were presented by a high expression of specific proteases, size variation, polymorphism, and variable ultrastructural phenotype of granules. A massive number of granules were released surrounding the degranulated MCs while the integrity of MC membrane was maintained. Granules were electron-dense with or without a membrane, ranging from 0.2 to 0.8 μm in diameter. MC plasmalemma was not found at the site of MC-collagen fibrils contact, whereas the secretome and fibrils were directly contacted. We observed direct and mediator-based interactions between MCs and paraganglioma cells. The latter preserved their membrane integrity when MC granules were not in proximity. The effects of the MC secretome on the paraganglioma microenvironment demonstrated its pathogenetic role in tumor progression and allow its application to new diagnostic criteria and the development of protocols for personalized therapy. RESEARCH HIGHLIGHTS: Ultrastructural analysis reveals novel regulatory effects of mast cells via diverse secretory pathways on the pathogenesis of parasympathetic paraganglioma, including fibrous extracellular matrix remodeling and mediator-based interactions between MCs and cells of the tumor microenvironment.

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.

Hereditary head and neck paraganglioma: from basics to practical consequences

PURPOSE OF REVIEW

This review summarizes practical recommendations for screening, work-up, and management of hereditary head and neck paragangliomas based on the growing molecular and empirical understanding of this disease.

RECENT FINDINGS

The proportion of hereditary cases among head and neck paragangliomas is significant (∼33 to 50%), and specific genetic alterations may increase the risk of malignancy. Genotyping should be performed for each case, and patients carrying a pathological mutation should be regularly screened for new tumors. Computed tomography (CT), magnetic resonance imaging (MRI), digital subtraction angiography (DSA), and functional positron emission tomography (PET) can provide a reliable preoperative diagnosis in the absence of histology. Comparative data on therapeutic outcome and morbidity now render radiation, stereotactic radiosurgery, and active surveillance preferable over surgery in highly advanced cases of jugulotympanic and vagal paragangliomas, whereas surgery remains the first choice for most carotid body paragangliomas.

SUMMARY

Complete paraganglioma removal continues to be the primary therapeutic goal; however, this is sometimes impossible to accomplish with acceptable morbidity. In these cases, therapy selection should focus on preserving cranial nerve function and minimizing both tumor-associated and therapy-associated complications, particularly in genetically predisposed patients. An interdisciplinary approach to the management of hereditary head and neck paragangliomas is strongly recommended.

Microsurgical treatment of carotid body tumors using periadventitial dissection: Analysis of outcomes and prognostic factors in a neurological referral center

Background:

Surgical resection for carotid body tumors (CBTs) is the gold standard of treatment and continues to be a challenging procedure, commonly associated with high vascular injury rates and neurological complications.

Methods:

It is a retrospective case series study between January 2002 and November 2020, with a mean follow-up of 29 months in a single nationwide referral center. Thirty-one patients diagnosed with a carotid body tumor and treated with microsurgical periadventitial resection were included in the study. Patients’ demographics, comorbidities, clinical, radiological factors, and tumor grade, evaluated by the Shamblin scale, were obtained. Statistical analysis was performed on all collected data.

Results:

In this study, we included 31 patients (32 tumors), 80% of the patients were female, and 20% were male, with a mean age of 53 years. One patient presented with bilateral lesions, while 17 tumors were located on the left side. The most frequent symptom was a painless, slow-growing neck mass in 74% of patients. Using the Shamblin classification, 13% of tumors were Grade I, 53% Grade II, and 34% Grade III. In the postoperative period, 3% of patients presented with permanent cranial nerve deficit, while none had vascular injuries or postoperative stroke. A tumor >5 cm increased the risk for nerve lesion by 11 times (OR 12.6, CI 95% 7.4-11.4, P < 0.001).

Conclusion:

Preoperative embolization followed by periadventitial resection by means of a microsurgical technique is a safe and effective approach to remove CBT, with 3% cranial nerve injury rate and no need for vascular sacrifice or reconstruction.

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 Four-Generational Report on Hereditary Head and Neck Paraganglioma

Background

This article investigates the inheritance, penetrance, clinical presentation, and therapeutic outcomes of hereditary head and neck paragangliomas (HNPGLs) by offering a four-generational report of an 18-member family affected by this rare condition.

Methodology

Information was compiled by examination of patients and a review of medical records and correspondence (retrospective case series).

Results

Six members of the 18-member family were diagnosed with HNPGL between 2002 and 2018. A known pathogenic point mutation in subunit D of the succinyl dehydrogenase complex (SDHD, c.317G>T, p.Gly106Val) was responsible for the tumor phenotype. The mutation could be revealed in seven family members, three diseased adults, one healthy adult, and three healthy children, out of the nine who consented to gene testing. The median age at diagnosis was 33.5 years (range: 22-50 years). Five of the eight primary tumors were glomus caroticum, two were glomus jugulare, and one was a glomus vagale tumor. The therapeutic approaches were multimodal and included embolization therapy, surgery, radiation, and watchful waiting. Follow-up was reported for five of the six patients (mean follow-up of 34.8 months after primary therapy); three showed no disease progression or recurrence.

Conclusions

This study exemplifies the autosomal dominant, parent-of-origin-dependent inheritance and the high disease penetrance in hereditary paraganglioma-pheochromocytoma syndromes. Six out of a total of eight adult descendants (75%) of the original SDHD mutation carrier developed tumors, and the morbidity associated with the disease as well as its therapy was especially high in late-diagnosed, advanced cases. This substantiates the necessity for early radiologic surveillance and genetic testing.

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.

Giant carotid chemodectoma treated with a combination of surgery and CyberKnife radiotherapy: a case report and review of the literature

Background

Paragangliomas are rare vascular neuroendocrine tumors that develop in the extra-adrenal paraganglion tissue. They occur most commonly at the carotid bifurcation, where they are known as carotid body tumors. Most paragangliomas are benign, locally aggressive, infiltrative tumors. Approximately 10% of patients with paragangliomas develop distant metastases, 10% present with multiple or bilateral tumors (mostly carotid body tumors), and 10% have a family history of paragangliomas. The malignant transformation of carotid body tumors has been reported in 6% of cases.

Case presentation

We present the case of a 64 year-old Caucasian woman with a gigantic glomic tumor mass in the neck. Twenty years before the consultation, the patient had undergone an unsuccessful attempt to remove the mass. Over the last 3 years, the patient had felt enlargement of the mass at an increased rate, almost doubling the prior size. Angio magnetic resonance imaging showed a 9 cm paratracheal mass on the left cervical side that laterally displaced the sternocleidomastoid muscle and 2 c m of the trachea. Due to the change in the tumor behavior, the maxillofacial team at Ruber International Hospital decided to remove the tumor surgically after embolization. During the surgery the tumor was gently dissected from the carotid an removed from the carotid bifurcation uneventfully. Two small nodes adhering tightly to the internal carotid adventitia and the posterior torn hole were left in place to avoid any potentially life-threatening complications. The final biopsy confirmed the initial diagnosis of carotid body paraganglioma and showed a Ki-67 expression of 19%. Due to the aggressive growth behavior and high Ki-67 expression of the tumor, the patient was referred to the CyberKnife Unit of Ruber International Hospital for treatment of the remaining nodes.

Conclusions

The management of cervical paragangliomas is difficult and remains a challenge. Although the likelihood of tumor control is high with surgical or radiotherapeutic treatments, we currently lack consensus regarding the best treatment option. Nevertheless, in selected complex cases, such as the case we present, the combination of surgery and radiosurgery may allow complete local tumor control with minimal morbidity.

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.

Hypofractionated Robotic Stereotactic Radiosurgery for Vagal Paragangliomas: A Novel Treatment Strategy for Cranial Nerve Preservation

OBJECTIVE

To provide the first description of hypofractionated stereotactic radiosurgery (SRS) and evaluate tumor control and safety for vagal paragangliomas (VPs), which begin at the skull base but often have significant extracranial extension.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary-referral neurotology and neurosurgery practice.

SUBJECTS AND METHODS

Five VPs in 4 patients (all male, ages 15-56 years) underwent SRS between 2010 and 2018. Outcome measures included tumor dimensions on serial imaging, cranial nerve function, and radiation side effects.

RESULTS

CyberKnife hypofractionated SRS was performed. The prescription dose was 24 or 27 Gy (maximum dose 33.4 Gy; range, 29.3-35.5 Gy) delivered in 3 equal fractions. The mean isodose line was 79% (range, 76%-82%). Four VPs were treated primarily, and 1 tumor underwent SRS to treat regrowth 2 years after microsurgical subtotal resection via the modified infratemporal fossa approach. The treatment volume ranged from 8.81 to 86.3 cm³ (mean, 35.7 cm³). All demonstrated stable size (n = 3) or regression (n = 2) at last follow-up, 63 to 85 months after SRS (mean, 76 months). One patient had stable premorbid vocal fold paralysis from a prior ipsilateral glomus jugulare tumor resection. All others demonstrated normal vagal function following SRS. Treatment-related side effects, including dysgeusia (n = 1), mucositis (n = 1), and neck soft-tissue edema (n = 2), were self-limited.

CONCLUSIONS

Hypofractionated SRS appears to be both safe and effective for treating VPs, including large-volume and predominantly extracranial tumors, while preserving vagal function. SRS should be considered as a cranial nerve preservation option, especially in settings of contralateral lower cranial nerve deficits or in those with multiple paragangliomas risking both vagal nerves.

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.

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.

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.

Germline mutations and genotype-phenotype associations in head and neck paraganglioma patients with negative family history in China

The aim of this study was to assess the frequency of germline mutations and to explore genotype-phenotype associations in Chinese head and neck paraganglioma (HNPGL) patients without family history. Twenty-six Chinese patients with a diagnosis of HNPGL（14 male and 12 female, respectively）were recruited, who were followed up from 2000 to 2012. Genomic DNA was obtained from resected tumor tissues and peripheral blood samples. Seven genes, Succinate dehydrogenase complex A,B,C,D (SDHA, SDHB, SDHC, SDHD), succinate dehydrogenase complex assembly factor 2 (SDHAF2), TMEM127 (transmembrane protein 127) and VHL (Von Hippel-Lindau), were screened by direct sequencing and multiplex ligation-dependent probe amplification (MLPA) was performed to search for potential large deletions or duplications of SDHB, SDHC, SDHD, SDHAF1 and SDHAF2. The total frequency of germline mutations was 30.8% (8/26), including 5 cases with missense mutation p.Met1Ile in SDHD, 1 case with missense mutation p.Tyr216Cys in SDHB, and 1 case with a novel truncation mutation p.Gln44Ter in SDHAF2. MLPA showed one patient with malignant HNPGL had heterozygous deletions of exon1, 2, 3, 7 and 8 in SDHB. Mutations in SDHD were the leading cause of HNPGL in this study. Mutation carriers were younger than non-mutation carriers (p < 0.01) and more likely to suffer from multiple tumors (p = 0.048), especially with mutations in SDHD. The presence of mutation was associated with the development of larger tumors (p = 0.021). This study confirmed that the missense mutation p.Met1Ile at the start codon in SDHD was a hotspot in chinese patients with HNPGLs. We recommend genetic analysis in patients below 45 years, especially SDHD gene.

Radiotherapy for benign head and neck paragangliomas: a 45-year experience

BACKGROUND

Paragangliomas of the head and neck are rare, slow-growing, generally benign tumors of neuroendocrine cells associated with the peripheral nervous system that commonly involve the carotid body, jugular bulb, vagal ganglia, and temporal bone. Treatment options include surgery, radiotherapy (RT), stereotactic radiosurgery (SRS), and observation. This article briefly reviews our 45-year institutional experience treating this neoplasm with RT.

METHODS

From January 1968 through March 2011, 131 patients with 156 benign paragangliomas of the temporal bone, carotid body, jugular bulb, or glomus vagale were treated with RT at a median dose of 45 Gy in 25 fractions. The mean and median follow-up times were 11.5 years and 8.7 years, respectively.

RESULTS

Five tumors (3.2%) recurred locally after RT, all within 10 years of treatment. The overall local control rates at 5 and 10 years were 99% and 96%, respectively. The cause-specific survival rates at 5 and 10 years were 98% and 97%, respectively. The distant-metastasis free survival rates at 5 and 10 years were 99% and 99%, respectively. The overall survival rates at 5 and 10 years were 91% and 72%, respectively. There were no severe complications.

CONCLUSION

RT for benign head and neck paragangliomas is a safe and efficacious treatment associated with minimal morbidity. Surgery is reserved for patients in good health whose risk of associated morbidity is low. SRS may be suitable for patients with skull base tumors <3 cm where RT is logistically unsuitable. Observation is a reasonable option for asymptomatic patients with a limited life expectancy.

Preoperative embolization of carotid chemodectoma: a technical challenge that can be customized according to angioarchitecture. Illustrative cases

Preoperative embolization of carotid paraganglioma is increasingly used to reduce the risk of surgical bleeding obtaining a more precise and extensive tumor resection. Currently the technique can be customized in consideration of the different tumor angioarchitecture, thanks to embolic materials with different vascular penetration: solid particles of polyvinyl-alcohol (PVA), histoacryl glue, and liquid polymer (Onyx(®)). Two cases of swelling dissection with volume progression over time came to our observation. Both patients (45 and 70-year-old women) were studied with neck ultrasound imaging and computed tomography (CT) and/or magnetic resonance (MR). In both cases the radiological investigations confirmed the clinical suspicion of carotid paraganglioma. Both patients were sent for angiography control and preoperative devascularization of the lesion. The treatment was performed under general anesthesia using, depending on the type of tumor vasculature, in case 1 solid particles of PVA and histoacryl glue, and in case 2 Onyx(®) (Covidien, Irvine). The patients successfully underwent excision of the lesion via cervicotomy within a week from the embolization procedure, without any complications. The histological findings confirmed the diagnosis of chemodectoma, and macrophage infiltrates were seen in the regions previously embolized. At one-year follow-up, there was no evidence of recurrent disease. The preoperative embolization of vascular lesions of the neck represents a safe technique that yields the best results when customized over the type of vascularization of the lesion, enabling the use of the most appropriate materials, depending on the case to be treated.

Malignant head and neck paragangliomas: treatment efficacy and prognostic indicators

PURPOSE

Malignant head and neck paragangliomas (MHNPs) are rare and occur in 6%-19% of all HNPs. We sought to identify predictors of survival and compare efficacy of treatment modalities to inform management of this rare disease.

MATERIALS AND METHODS

We performed a retrospective cohort study of MHNP cases in the National Cancer Institute Surveillance Epidemiology and End Results database (SEER) from 1973 to 2009. We identified 86 patients with MHNP who had documented regional or distant tumor spread with a median follow-up of 74 months. We used Cox proportional hazard models to assess the significance of demographic factors and treatment on five-year overall survival.

RESULTS

The most common treatment was surgery alone (36.0 %), followed by surgery with adjuvant radiation (33.7%). Five-year overall survival was 88.1% for surgery alone and 66.5% for adjuvant radiation (p = 0.2251). In univariate analysis, regional (vs. distant) spread (HR 0.23, p < 0.0001), surgery alone (HR 0.29, p < 0.0001) and primary site in the carotid body (HR 0.32, p = 0.006) conferred significant survival advantage whereas age > 50 (HR 4.04, p < 0.0001) worsened survival. Regional (vs. distant) spread (HR 0.42, p = 0.046) and age > 50 (HR 2.98, p = 0.005) remained significant in multivariate analysis. In patients with regional-only disease, five-year overall survival was 95.4% for surgery alone compared to 75.6% for surgery with radiation (p = 0.1055).

CONCLUSIONS

This is the largest and most contemporary series of MHNP patients. Age and tumor stage are significant factors in predicting survival. Surgical resection significantly improves survival outcomes. From this analysis, the value of adjuvant radiation is not clear.

Neurological complications in carotid body tumors: a 6-year single-center experience

OBJECTIVE

Carotid body tumors are considered rare. However, there has been an increase in the number of these tumors managed at our center in recent years. Delayed presentation with large tumors is common. We studied the clinical profile, interventions, and outcomes of these tumors and assessed the factors influencing operative neurological morbidity and recurrence.

METHODS

This retrospective study was conducted at the Christian Medical College in Vellore, a tertiary care center in south India. We analyzed the inpatient and outpatient records of patients diagnosed to have carotid body tumors undergoing excision from January 1, 2005 to December 31, 2011. Patients diagnosed to have vagal paragangliomas were excluded.

RESULTS

Thirty-four of 48 tumors were excised from 32 patients (11 female, 21 male). Average age at presentation was 38.2 years, and three patients had familial bilateral tumors. All patients presented with a painless neck mass. There were 27 Shamblin group III, six Shamblin group II, and one Shamblin group I tumor. Eleven Shamblin group II/III tumors were associated with transient cranial nerve palsy or paresis (32.3%). Two Shamblin group III tumors were associated with perioperative stroke (5.8%). Preoperative embolization was done in 17 tumors, 12 of which were associated with neurological complications (two stroke, nine nerve palsy, one hemianopia). One patient underwent thrombolysis for a middle cerebral artery thrombus and recovered completely on follow-up, and another with a capsuloganglionic infarct managed conservatively had minimal persistent disability. Three patients had persistent nerve palsy (8.8%). Although complications were more common in patients with higher Shamblin group tumors, the difference was not statistically significant.

CONCLUSIONS

The overall rate of neurological complications is higher with tumors of higher Shamblin groups. Preoperative embolization was not effective in reducing neurological complications. The rates of postoperative stroke and permanent cranial nerve palsy after resection of large tumors are acceptable.

Primary sclerosing paraganglioma of the thyroid gland: a case report

OBJECTIVES

Paragangliomas are neuroendocrine tumors derived from extra-adrenal paraganglionic cells of the autonomic nervous system. Paragangliomas of the thyroid are rare, with only 28 cases reported in the literature. The sclerosing paraganglioma variant, characterized by marked stromal sclerosis and hyalinization, has scarcely been reported.

METHODS

A 36-year-old woman with a history of a 1-cm vagal schwannoma followed with serial magnetic resonance imaging presented with a new solitary 2.5-cm enhancing soft tissue mass in the left thyroid.

RESULTS

Ultrasound examination of the thyroid revealed a hypoechoic, hypervascular, malignant-appearing mass. Two fine-needle aspirations were insufficient for diagnosis, and the mass was deemed a lesion of undetermined significance with subsequent indeterminate molecular testing. A diagnostic left thyroid lobectomy was performed, and pathologic examination revealed a lesion consistent with a sclerosing paraganglioma.

CONCLUSIONS

Sclerosing paragangliomas are rare tumors, and only 1 case involving a primary thyroid mass has been reported in the literature. Although the sclerosing variant has features suggestive of malignancy, the true incidence of malignancy is unknown, given the rarity of its presentation. However, given the overall benign nature of paragangliomas, the sclerosing variant is also likely benign, despite its malignant features on ultrasound and histopathologic examination.

Genetic and clinical characteristics of head and neck paragangliomas in a Chinese population

OBJECTIVES/HYPOTHESIS

Head and neck paragangliomas (PGLs) are rare and frequently associated with germline mutations of the succinate dehydrogenase (SDH) genes, especially for familial cases. The purpose of the study was to explore genetic and clinical characteristics of head and neck PGLs in a Chinese population.

STUDY DESIGN

Retrospective review.

METHODS

One hundred thirty-two patients who had undergone resection for head and neck PGLs between 1975 and 2010 were identified. Clinical characteristics and outcomes were reviewed. Analysis of the SDH genes was performed in 29 patients and one kindred with familial PGL to identify germline mutations in the SDHB, SDHC, and SDHD genes by direct DNA sequencing.

RESULTS

There were 69 male (52.3%) and 63 female (47.76%) patients, with a mean age of 43.6 years (range, 13-72 years). Most lesions (61.4%) were PGLs of the carotid bifurcation. Others included jugular (25.0%), vagal (9.1%), and tympanic PGLs. Twenty-one patients (15.9%) had multiple PGLs, 25 patients (18.9%) had a malignant PGL, and 15 patients (11.4%) in four families were familial PGLs. Analysis of the SDH genes in 29 patients showed that four familial cases (including two patients) carried a heterozygotic missense mutation in SDHD. The mutation was W43X, located in SDHD-exon 2. Four sporadic cases carried samesense germline mutations in SDHB-exon 1, and they were all malignant PGLs.

CONCLUSIONS

Multifocal occurrence, potential malignancy, and genetic aspect should be considered in patients with head and neck PGLs. The high frequency of founder mutations in SDHB suggests a higher prevalence of malignancy, and the SDHD mutation is usually associated with familial cases.

Diagnostic tests and biomarkers for pheochromocytoma and extra-adrenal paraganglioma: from routine laboratory methods to disease stratification

The laboratory workup of patients with pheochromocytoma and extra-adrenal paraganglioma (PPGLs) has traditionally focused on biochemical measurements of tumor secretory products or their metabolites, with ultimate diagnosis resting on routine histopathology and immunohistochemistry. While such testing remains important, the needs to distinguish potentially metastatic from benign tumors and to identify tumors with a hereditary basis have stimulated searches for additional means to stratify patients according to risk of metastasis or presence of a particular mutation. Biomarkers based on traditional biochemical tests, such as profiles of catecholamine metabolites and granin-derived peptides, provide utility for both purposes, while novel biomarkers are being identified by proteomic and transcriptomic studies, the latter including microRNA expression profiling. Histopathological scoring methods for predicting metastatic potential, such as the Pheochromocytoma of the Adrenal Gland Scaled Score (PASS), are limited by poor interobserver concordance, discrepant results between studies and incomplete knowledge of how scores relate to genotype. Immunohistochemical staining for succinate dehydrogenase (SDH) subunit B to triage patients for genetic testing of SDH subunit genes illustrates the growing importance of pathology as an adjunct to genetic testing for disease stratification. Although considerable effort has been expended on microarray-based platforms to identify biomarkers of malignancy, as yet, none of those proposed have been demonstrated to reliably discriminate malignant from benign disease any better than the PASS. Because of the heterogeneity of PPGLs and variable time between first appearance of tumors and identification of metastases, any prospective study to establish prognostic efficacy requires large numbers of patients and extended follow-up.