Molecular genetics of paragangliomas of the skull base and head and neck region: implications for medical and surgical management

Algorithm of genetic diagnosis for patients with head and neck paraganglioma-update

Paragangliomas are rare tumors originating from the paraventricular bodies of the autonomic nervous system located in the adrenal glands, chest, abdomen, pelvis and head and neck. Tumors of this type account for 0.5% of head and neck cancers, 0.03% of all cancers and their incidence is estimated at 1-30/100,000 per year. Head and Neck Paragangliomas (HNPGL) are localized in carotid body, tympanic cavity or jugular foramen. It is established that HNPGL may be associated with mutations of the SDH complex, with SDHD being the most prevalent. However, SDHB, SDHC and SDHAF are also potential causes. The aforementioned mutations are influenced by various risk factors, including young age, a positive family history of paraganglioma, the presence of metastases and gender The purpose of this study is to summarize the results of genetic testing performed on patients with head and neck paraganglioma and to create an up-to-date genetic diagnosis algorithm for patients with HNPGL based on previous studies published in the literature that can be used in daily practice. Several papers observed that among SDHD mutation carriers, most or all of those studied had HNPGL, and SDHB mutations were more frequently found in the presence of metastasis. Based on the results, it was concluded that there is no basis for genetic testing for VHL in patients without a positive family history. In each algorithm proposed by different authors, proposals for rational genetic diagnosis were analyzed based on the studies cited by the author and the analyses included in our paper. For the analysis of the treatment algorithms, the following were included: Martin, Mannelli, Neumann, Gupta. Subsequently, publications related to the genetic diagnosis of HNPGL were analyzed to verify the proposed algorithms in light of the latest genetic studies and to establish an updated diagnostic management scheme.

Endoglin in head and neck neoplasms

Tumors of the head and neck region form a heterogeneous group of pathologies, including various benign lesions and malignant neoplasms. Endoglin, also known as CD105, is an accessory receptor for transforming growth factor beta (TGF-β), that regulates angiogenesis, both under physiological and pathological conditions. It is highly expressed in proliferating endothelial cells. Therefore, it is considered as a marker of tumor-related angiogenesis. In this review we discuss the role of endoglin as a possible marker of carcinogenesis, as well as a potential target for antibody-based therapies in the neoplasms of the head and neck region.

Multidisciplinary management of carotid body tumors: a single-institution case series of 22 patients

OBJECTIVE

Carotid body tumors (CBTs) are rare, slow-growing neoplasms derived from the parasympathetic paraganglia of the carotid bodies. Although inherently vascular lesions, the role of preoperative embolization prior to resection remains controversial. In this report, the authors describe an institutional series of patients with CBT successfully treated via resection following preoperative embolization and compare the results in this series to previously reported outcomes in the treatment of CBT.

METHODS

All CBTs resected between 2013 and 2019 at a single institution were retrospectively identified. All patients had undergone preoperative embolization performed by interventional neuroradiologists, and all had been operated on by a combined team of cerebrovascular neurosurgeons and otolaryngology-head and neck surgeons. The clinical, radiographic, endovascular, and perioperative data were collected. All procedural complications were recorded.

RESULTS

Among 22 patients with CBT, 63.6% were female and the median age was 55.5 years at the time of surgery. The most common presenting symptoms included a palpable neck mass (59.1%) and voice changes (22.7%). The average tumor volume was 15.01 ± 14.41 cm3. Most of the CBTs were Shamblin group 2 (95.5%). Blood was predominantly supplied from branches of the ascending pharyngeal artery, with an average of 2 vascular pedicles (range 1-4). Fifty percent of the tumors were embolized with more than one material: polyvinyl alcohol, 95.5%; Onyx, 50.0%; and N-butyl cyanoacrylate glue, 9.1%. The average reduction in tumor blush following embolization was 83% (range 40%-95%). No embolization procedural complications occurred. All resections were performed within 30 hours of embolization. The average operative time was 173.9 minutes, average estimated blood loss was 151.8 ml, and median length of hospital stay was 4 days. The rate of permanent postoperative complications was 0%; 2 patients experienced transient hoarseness, and 1 patient had medical complications related to alcohol withdrawal.

CONCLUSIONS

This series reveals that endovascular embolization of CBT is a safe and effective technique for tumor devascularization, making preoperative angiography and embolization an important consideration in the management of CBT. Moreover, the successful management of CBT at the authors' institution rests on a multidisciplinary approach whereby endovascular surgeons, neurosurgeons, and ear, nose, and throat-head and neck surgeons work together to optimally manage each patient with CBT.

Clinical outcomes following resection of paraspinal ganglioneuromas: a case series of 15 patients

OBJECTIVE

Paraspinal ganglioneuromas are rare tumors that arise from neural crest tissue and can cause morbidity via compression of adjacent organs and neurovascular structures. The authors investigated a case series of these tumors treated at their institution to determine clinical outcomes following resection.

METHODS

A retrospective review of a prospectively collected cohort of consecutive, pathology-confirmed, surgically treated paraspinal ganglioneuromas from 2001 to 2019 was performed at a tertiary cancer center.

RESULTS

Fifteen cases of paraspinal ganglioneuroma were identified: 47% were female and the median age at the time of surgery was 30 years (range 10-67 years). Resected tumors included 9 thoracic, 1 lumbar, and 5 sacral, with an average maximum tumor dimension of 6.8 cm (range 1-13.5 cm). Two patients had treated neuroblastomas that matured into ganglioneuromas. One patient had a secretory tumor causing systemic symptoms. Surgical approaches were anterior (n = 11), posterior (n = 2), or combined (n = 2). Seven (47%) and 5 (33%) patients underwent gross-total resection (GTR) or subtotal resection with minimal residual tumor, respectively. The complication rate was 20%, with no permanent neurological deficits or deaths. No patient had evidence of tumor recurrence or progression after a median follow-up of 68 months.

CONCLUSIONS

Surgical approaches and extent of resection for paraspinal ganglioneuromas must be heavily weighed against the advantages of aggressive debulking and decompression given the complication risk of these procedures. GTR can be curative, but even patients without complete tumor removal can show evidence of excellent long-term local control and clinical outcomes.

[Jugulotympane paraganglioma associated with polysegmentary congenital hemangioma]

The describes a clinical observation of a combination of jugulotympanic paraganglioma of the left temporal bone with multifocal congenital hemangioma. The interest of the case is that such a combination of pathologies is extremely rare. A comprehensive study and surgical treatment of a patient with this clinical diagnosis was carried out. In the diagnosis, objective otorhinolaryngological studies, otomicroscopy and MSCT of the temporal bones and MRI of the middle ear with contrast were used. Surgical intervention was performed under multicomponent anesthesia with tracheal intubation, transmastoid access. The postoperative management of the patient after surgical treatment is described.

Simple and complex carotid paragangliomas. Three decades of experience and literature review

BACKGROUND

Carotid paragangliomas are rare tumors. They are usually unique, non-secreting, resectable, and benign. However, additional rare cases of complex tumors (bilateral, secretory, nonresectable, or malignant) complicate the management and final outcomes.

METHODS

Records of paragangliomas from our hospital are reviewed. Criteria defining complex paragangliomas have been previously defined. These are compared with those of the simple group.

RESULTS

Fifty patients, two groups: simple (n = 39) and complex (n = 11). The patients in the complex group were significantly younger (47.7 vs 63.8 years). Postoperative nerve complications (45.4% vs 6.3%) and mortality during follow-up (27.3% vs 0%) were significantly more common in the complex group. Vascular complications (0% vs 3.1%) and early mortality (0%) were similarly in both groups.

CONCLUSIONS

Patients with complex carotid paragangliomas are heterogeneous. The former are younger, exhibit a high degree of diagnostic and therapeutic complexity, and have poorer morbidity and mortality. Surgical experience and interdisciplinary collaboration are essential.

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.

Initial experience with dual-lumen balloon catheter injection for preoperative Onyx embolization of skull base paragangliomas

OBJECT

Paragangliomas are highly vascular head and neck tumors for which preoperative embolization is often considered to facilitate resection. The authors evaluated their initial experience using a dual-lumen balloon to facilitate preoperative embolization in 5 consecutive patients who underwent preoperative transarterial Onyx embolization assisted by the Scepter dual-lumen balloon catheter between 2012 and 2014.

OBJECT

The authors reviewed the demographic and clinical records of 5 patients who underwent Scepter-assisted Onyx embolization of a paraganglioma followed by resection between 2012 and 2014. Descriptive statistics of clinical outcomes were assessed.

RESULTS

Five patients (4 with a jugular and 1 with a vagal paraganglioma) were identified. Three paragangliomas were embolized in a single session, and each of the other 2 were completed in 3 staged sessions. The mean volume of Onyx used was 14.3 ml (range 6–30 ml). Twenty-seven vessels were selectively catheterized for embolization. All patients required selective embolization via multiple vessels. Two patients required sacrifice of parent vessels (1 petrocavernous internal carotid artery and 1 vertebral artery) after successful balloon test occlusion. One patient underwent embolization with Onyx-18 alone, 2 with Onyx-34 alone, and 1 with Onyx-18 and −34. In each case, migration of Onyx was achieved within the tumor parenchyma. The mean time between embolization and resection was 3.8 days (range 1–8 days). Gross-total resection was achieved in 3 (60%) patients, and the other 2 patients had minimal residual tumor. The mean estimated blood loss during the resections was 556 ml (range 200–850 ml). The mean postoperative hematocrit level change was −17.3%. Two patients required blood transfusions. One patient, who underwent extensive tumor penetration with Onyx, developed a temporary partial cranial nerve VII palsy that resolved to House-Brackmann Grade I (out of VI) at the 6-month follow-up. One patient experienced improvement in existing facial nerve weakness after embolization.

CONCLUSIONS

Scepter catheter-based Onyx embolization seems to be safe and effective. It was associated with excellent distal tumor vasculature penetration and holds promise as an adjunct to conventional transarterial Onyx embolization of paragangliomas. However, the ease of tumor penetration should encourage caution in practitioners who may be able to effect comparable improvement in blood loss with more conservative proximal Onyx penetration.