Vagal paragangliomas

Tumor volume changes after stereotactic, hypofractionated and conventional radiotherapy in paragangliomas of head and neck

BACKGROUND

The aim of this study is comparison the effectiveness of stereotactic, hypofractionated and conventional radiotherapy assessed by the tumor volume changes of paraganglioma located in the head and neck region concerning fractional and total doses.

METHODS

We analyzed 76 patients after radiotherapy due to paraganglioma who were assigned to 3 groups considering fractional (≤2 Gy, 3-5.5 Gy, ≥6 Gy) and total (≤20 Gy, 21-40 Gy, >40 Gy) doses. The volumes of irradiated tumors were measured and compared based on diagnostic images performed before and after the treatment.

RESULTS

The mean tumor volume after the treatment with the lowest fractional dose (≤2 Gy) was decreased by 14.4 cm3. In patients treated with higher fractional doses (>2 Gy), the mean tumor volumes decreased by less than 1 cm3 for hypofractionated and stereotactic radiotherapy. 15.9 cm3 reduction of the mean tumor volume after the treatment with the highest RT total dose (>40 Gy) was stated. In patients treated with total doses ≤20 Gy and 21-40 Gy, the mean tumor volume was stable and reduced by 1.15 cm3, respectively. The analysis demonstrates a statistically significant (p < 0.05) treatment advantage in patients after the lowest fractional and highest total doses.

CONCLUSION

The reduction of the tumor's volume was reported after conventional and unconventional radiotherapy. The most significant depletion of the paraganglioma volume was noted after a factional dose ≤2 Gy and a total dose >40 Gy.

An Unusual and Discrepant Presentation of a Skull Base Paraganglioma

Paragangliomas are rare tumors of neuroendocrine origin. Within the head and neck, these tumors are slow-growing and locally destructive, with a small malignant potential. Vagal paragangliomas (VPs) originate from paraganglia around the vagus nerve, typically at the level of the skull base. Cranial nerve deficits are common at presentation, with the vagus nerve and hypoglossal nerves being most affected. Similarly, hypoglossal paragangliomas (HPs) originate from around the hypoglossal nerve but are extremely rare and less documented. We describe the case of a patient presenting with an isolated hypoglossal nerve palsy in the setting of a tumor that radiologically represents a VP. A descriptive literature review was conducted to highlight presentation, management, and outcomes related to this pathology. A 65-year-old male presented to the clinic with tongue fasciculations and several years of dysarthria. Physical examination showed intermittent right tongue fasciculations in addition to ipsilateral hemi-atrophy. A computed tomography scan with contrast revealed an enhancing skull base mass inferior to the right carotid space. Subsequently, magnetic resonance imaging with contrast further delineated its anatomic involvement and site of origin, allowing for the diagnosis of a VP. After further discussion with the patient about his clinical findings, the decision was made to proceed with observation and serial imaging. Skull base paragangliomas are a rare pathologic entity that may pose a challenging multidisciplinary approach to optimize management strategies. Treatment may vary on a case-by-case basis and is dependent on patient and tumor characteristics.

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

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

Hereditary Paraganglioma Syndrome Associated with SDHD Gene Mutations: A Patient with Multicentric Presentation Treated with Radiotherapy. Case Report

Introduction

Extra-adrenal paragangliomas are rare tumors arising from neuroendocrine cells. Sporadic and hereditary forms have been recognized. Among the latter, the PGL1 and PGL4 syndromes are associated with a high risk of multiple localizations. The treatment of choice for paragangliomas is surgical resection, but in some cases surgery can be difficult due to particular or multiple tumor sites or may result in severe neurological deficits. In such cases radiotherapy can be an effective alternative. In this paper we describe the case of a patient affected by hereditary paraganglioma syndrome with multicentric presentation who was treated at our center by external radiotherapy.

Case report

A 55-year-old man presented in April 2008 with multiple paragangliomas: one in the left pontocerebellar angle, two in the middle neck, one mediastinal paraaortic mass, and an abdominal paraaortic lesion. The left pontocerebellar and mediastinal tumors were treated with three-dimensional conformal radiotherapy (3D-CRT) at total doses of 50.40 Gy and 55.80 Gy, respectively. The neck lesions were treated with intensity-modulated radiotherapy (IMRT) at a total dose of 55.80 Gy. The abdominal paraaortic lesion was surgically resected.

Results

No severe acute or late toxicity as evaluated with the EORTC-RTOG scale was observed. Fourteen months after the end of radiotherapy a whole body CT scan showed that the tumor lesions were stable in size and in their relations to contiguous structures. The arterial pressure was controlled by medical therapy and urine catecholamine levels were within the normal range.

Conclusions

We believe that in patients affected by unresectable paragangliomas radiotherapy is a safe and effective alternative to surgery. The use of high-dose conformity techniques such as 3D-CRT and IMRT will allow higher local control rates with relatively few side effects thanks to the possibility of dose escalation and reduction of the amount of irradiated healthy tissues.

Age and Tumor Volume Predict Growth of Carotid and Vagal Body Paragangliomas

Objective  Treatment for head and neck paragangliomas (HNGPL) can be more harmful than the disease. After diagnosis, an initial period of surveillance is often indicated, and surgery or radiotherapy is reserved for progressive disease. With the aim to optimize this "wait and scan" strategy, we studied growth and possible predictors. Design  A retrospective cohort study was conducted. Setting  This study was conducted at a tertiary referral center for patients with HNGPL. Methods  Tumor volume was estimated for 184 SDHD -related carotid and vagal body paragangliomas using sequential magnetic resonance imaging. Cox regression was used to study predictors of tumor growth. Results  The estimated fraction of growing tumors ranged from 0.42 after 1 year of follow-up to 0.85 after 11 years. A median growth rate of 10.4 and 12.0% per year was observed for carotid and vagal body tumors, respectively. Tumor location, initial volume, and age ( p  < 0.05) were included in our prediction model. The probability of growth decreased with increasing age and volume, indicating a decelerating growth pattern. Conclusions  We created a prediction model (available online), enabling a more individualized "wait and scan" strategy. The favorable natural course of carotid and vagal body paragangliomas was confirmed; although with long follow-up growth will be observed in most cases.

Head and Neck Paragangliomas

Objective

Head and neck paragangliomas are a group of slow-growing hypervascular tumors associated with the paraganglion system. The approach to evaluate and treat these lesions has evolved over the last 2 decades. While radical surgery had been the traditional approach, improvements in diagnostic imaging as well as radiation therapy techniques have led to an emphasis on observation and nonsurgical therapy in many patients. This article reviews the contemporary approach to the workup and management of head and neck paragangliomas.

Data Source

Articles were identified from PubMed.

Review Methods

PubMed searches with the following keywords were performed: carotid body paraganglioma management, vagal paraganglioma management, jugulotympanic paraganglioma management, imaging of head and neck paragangliomas, head and neck paraganglioma embolization, paraganglioma radiation, head and neck paraganglioma management, observation of head and neck paragangliomas, bilateral carotid body paragangliomas, and genetics of paragangliomas. Review and original research articles available in the English language and published during or after 2009 were selected on the basis of their clinical relevance and scientific strength. Certain articles published prior to 2009 were also included if they provided background information that was relevant.

Conclusions/Implications for Practice

Workup and treatment of head and neck paragangliomas are changing. With more now known regarding the longitudinal behavior of these tumors, observation and nonsurgical therapy are indicated in many instances. For patients where surgery is the most appropriate option, improved diagnostic and perioperative techniques are allowing patients to tolerate resection, often with reduced morbidity.

Cervical paragangliomas-tumor control and long-term functional results after surgery

OBJECTIVE

To report long-term functional results of the surgical treatment of cervical paragangliomas.

PATIENTS AND METHODS

A retrospective review of 22 patients with 34 head and neck paragangliomas of which 27 were resected between 1981 and 2004. Of these, 16 were carotid body tumors and 11 were vagal paragangliomas. There were 13 women and 9 men with an average age of 48.6 years (range, 26 to 75 years; median, 49 years) and the mean follow-up period was 82 months (range, 3 to 184 months; median, 61 months).

RESULTS

There were 13 solitary tumors of which 5 were carotid body tumors and 8 vagal paragangliomas. Multiple head and neck paragangliomas were seen in 9 patients (41%). The incidence of associated multiple tumors was 64.3% for carotid body tumors and 38.5% for vagal paragangliomas. Complete tumor resection was achieved in all but 1 patient in whom a small intradural residual vagal paraganglioma had to be left. The internal carotid artery was preserved in all carotid body tumor resections. Lower cranial nerve deficits were sustained in 1 carotid body tumor resection only, but in all cases with multiple tumors. All patients with vagal paragangliomas had or developed a vagal nerve paralysis. In 4 cases minor complications developed postoperatively. No recurrent tumors were seen during the follow-up period.

CONCLUSIONS

Even in large head and neck paragangliomas surgical treatment provides excellent tumor control with low postoperative morbidity. A wait-and-scan policy may be more appropriate for those patients with multiple tumors, advanced age, or high operative risk and for those whose tumors have recurred following radiotherapy.

The glossopharyngeal, vagus and spinal accessory nerves

The glossopharyngeal, vagus and spinal accessory nerves are closely related anatomically, and to a certain extent, functionally. We present an overview of their anatomy, highlighting the important clinical and imaging implications. The main pathologic lesions arising from these nerves are also discussed and the imaging features reviewed.

Bilateral glomus tumor treated with PET-CT based conformal radiotherapy: a case report

Introduction

Glomus tumors are benign, slow growing tumors originating from paraganglionic tissue, mostly located at the carotid bifurcation, jugular foramen, cervical portion vagus nerve, and middle ear cavity. Radiotherapy is treatment of choice for patients with intracranial extension, and patients with bilateral and multiple tumors, or patients who are inoperable.

Case presentation

We present a 53-year-old female patient with a glomus tumor treated with positron emission tomography computed tomography planning and 3D conformal radiotherapy, and the patient has remained free of disease progression 2 years after.

Conclusion

It is suggested that radiotherapy is a good treatment modality in patients with glomus tumor, and metabolic imaging and treatment planning with positron emission tomography computed tomography is superior to other imaging modalities.

Temporal paragangliomas

Temporal paragangliomas (PGL) are usually limited to the paraganglionar system with a sporadic or familial origin. Familial PGL have recently been shown to be associated with germline alterations in SDH group of genes, and occasionally are associated with a variety of genetic multisystemic disorders (von Hippel-Lindau disease, multiple endocrine neoplasia type 2 and neurofibromatosis type 1). Temporal bone PGL are normally located in the region of the jugular foramen and on the promontory along the Jacobson nerve. Occasionally, vagal PGL may reach the jugular foramen and behave as jugular PGL. Treatment of temporal PGL must be based on the biological behavior of the tumour, age and medical condition of the patient, location and size of the PGL, and potential for treatment induced morbidity. The main treatment modalities for PGL are surgery and radiation therapy. Patients with large temporal PGL whose resection would result in potentially disabling morbidity are often selected for radiation therapy or wait and scan policy. Small tympanic PGL where resection may be carried out with a low morbidity risk can be removed through an endomeatal tympanotomy. Jugular PGL limited to the infralabyrinthine region involving only the vertical segment of the ICA, can benefit of an extended facial recess approach, which allows a postoperative normal hearing and facial nerve function. For more extensive disease in the middle ear or around the ICA, external auditory canal preservation is not possible and some kind of facial nerve mobilization is required. Preservation of lower cranial nerves is facilitated by intrabulbar dissection, previous extradural ligation of the sigmoid sinus. Management of large intracranial involvement is controversial, although most authors advocate resection of the tumour in a single stage. Surgical control of the tumour can be expected in 70-85% of the patients and is clearly dependent on the tumour stage. Tumour size determines success in hearing and lower cranial nerves preservation.

Imaging the cranial nerves: part II: primary and secondary neoplastic conditions and neurovascular conflicts

There have been unprecedented improvements in cross-sectional imaging in the last decades. The emergence of volumetric CT, higher field MR scanners and higher resolution MR sequences is largely responsible for the increasing diagnostic yield of imaging in patients presenting with cranial nerve deficits. The introduction of parallel MR imaging in combination with small surface coils allows the depiction of submillimetric nerves and nerve branches, and volumetric CT and MR imaging is able to provide high quality multiplanar and curved reconstructions that can follow the often complex course of cranial nerves. Seeking the cause of a cranial nerve deficit is a common indication for imaging, and it is not uncommon that radiologists are the first specialists to see a patient with a cranial neuropathy. To increase the diagnostic yield of imaging, high-resolution studies with smaller fields of view are required. To keep imaging studies within a reasonable time frame, it is mandatory to tailor the study according to neuro-topographic testing. This review article focuses on the contribution of current imaging techniques in the depiction of primary and secondary neoplastic conditions affecting the cranial nerves as well as on neurovascular conflicts, an increasingly recognized cause of cranial neuralgias.

Imaging and management of head and neck paragangliomas

Paragangliomas of the head and neck are highly vascular lesions originating from paraganglionic tissue located at the carotid bifurcation (carotid body tumors), along the vagus nerve (vagal paragangliomas), and in the jugular fossa and tympanic cavity (jugulotympanic paragangliomas). Diagnostic imaging can be considered in two clinical situations: (1) patients who present with clinical symptoms suggestive of a paraganglioma, and (2) individuals from families with hereditary paragangliomas. It is not only necessary to detect and characterize the lesion, but also to study the presence of multiplicity. For these purposes, MR imaging, and especially 3D TOF MRA, is the modality of choice. CT scanning is especially useful to show destruction of the temporal bone. Angiography in combination with embolization will mainly be used prior to surgical resection, but can also be used for diagnostic purposes when the diagnosis is not yet clear. Many parameters play a role in the decision to treat of which multifocality and impairment of cranial nerves are the most important. The primary therapeutic option for paragangliomas is complete excision of tumor with preservation of vital neurovascular structures. Resection however, should be balanced against a more conservative "wait and scan" policy or palliative treatments such as radiotherapy.

Management of vagal paraganglioma: Is operative resection really the best option?

BACKGROUND

Vagal paragangliomas cannot be resected without sacrifice of the vagal nerve. The risk of bilateral vocal cord palsy has been reason to postpone treatment of this benign and slow growing neoplasm in hereditary cases. Postponement could be considered for solitary cases as well.

METHODS

An institute-based review of 48 patients with vagal paragangliomas over the past 30 years was performed.

RESULTS

Forty-eight patients with 58 vagal paragangliomas were studied. All but 4 patients had multiple paragangliomas and should be considered hereditary cases. The 10 patients that underwent an operation lost the vagal nerve; 60% of them had additional cranial nerve palsy postoperatively. In the group of patients who were followed for an average period of 8.5 years, 3 patients (8%) developed cranial nerve palsy.

CONCLUSIONS

Aggressive treatment of vagal paragangliomas leads to unnecessary early loss of vagal nerve function. A period of clinical and radiologic follow-up preceding an operation may lead to prolonged preservation of voice and swallowing functions in these patients, without grave consequences for other lower cranial nerves.

Recurrent laryngeal nerve paralysis: anatomy and etiology

Etiologies of adult vocal paralysis are varied by the site of the lesion as well as the extent and cause of the damage. Most large series point to surgery and neoplastic causes for recurrent nerve paralysis. A detailed history is important when working up a patient with this voice disorder. Knowledge of the anatomy of the head, neck, and chest as well as the mechanisms behind vocal fold paralysis is essential in the evaluation and treatment of recurrent nerve paralysis. Many of the surgical and traumatic causes of hoarseness are from compression type injuries. Recovery is dependent on the type, extent, and site of nerve lesion. Familiarity with this data allows the otolaryngologist to tailor management to suit each patient with vocal fold paralysis.