Chemodectoma of the head and neck: results of treatment in 84 patients

A Global Bibliometric Analysis of the Top 100 Most Cited Articles on Carotid Body Tumors

The carotid body, situated at the common carotid artery bifurcation, comprises specialized glomus cells responsible for sensing blood oxygen, carbon dioxide, pH, and temperature changes, crucial for regulating breathing and maintaining oxygen homeostasis. Carotid body tumors (CBTs), arising from these cells, are rare, representing only 0.5% of head and neck tumors, often presenting as benign, slow-growing, vascularized masses. In February 2023, this bibliometric analysis was conducted, which involved screening 1733 articles from the Web of Science database. The screening process was based on citation count, and articles were selected for inclusion based on specific criteria that focused on CBTs located within the carotid bifurcation. Rigorous selection involved independent screening and data extraction by four authors. The top 100 articles, published between 1948 and 2019, totaled 6623 citations and were authored by 98 unique first authors from 22 countries and 77 institutions, spanning 42 journals. Treatment articles were the predominant category, comprising 49% of the literature. This analysis offers insights into publication trends, identifies literature gaps, and outlines areas of research focus, providing a valuable resource to guide future studies on CBTs.

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.

Jugulotympanic paragangliomas in southern Finland: a 40-year experience suggests individualized surgical management

Treatment of jugulotympanic paragangliomas (JTPGLs) remains challenging with no clear guidelines for management or follow-up. The aim of this retrospective case-note study was to assess long-term results of operatively and conservatively managed JTPGLs between years 1974-2013. A total of 36 patients with JTPGLs were identified. Clinical characteristics and management outcomes of patients were reviewed. Data were extracted on demographics, symptoms, timing of diagnosis, tumor location and size, embolization, and management, including pre- and post-operative imaging, analysis of operative techniques, and follow-up. Pulsatile tinnitus and hearing loss were the most common presenting symptoms. Thirty-four (94 %) patients were treated with primary surgical therapy and two (6 %) with radiotherapy. The surgical approaches included endaural approach for Fisch Class A tumors and a variety of approaches for Fisch Class B-D tumors with an increasing predilection for function-preserving surgery. Eight (24 %) patients received subtotal resection. Five (15 %) patients had a local recurrence within 10 years after primary surgery. Two (6 %) patients suffered a permanent cranial nerve (CN) deficit after primary surgery. We advocate radical surgery when tumor resection is possible without compromising CNs. Function-preserving surgery with at least a 10-year follow-up for Fisch Class B-D tumors should be considered if CNs are in danger.

Treatment of Head and Neck Paragangliomas

Background

Commonly occurring in the head and neck, paragangliomas are typically benign, highly vascular neoplasms embryologically originating from the extra-adrenal paraganglia of the neural crest. Frequently, these tumors are associated with the vagus, tympanic plexus nerve, the carotid artery, or jugular bulb. Their clinical presentation can vary across a wide spectrum of signs and symptoms.

Methods

We reviewed and compared standard treatment approaches for paragangliomas of the head and neck.

Results

In general, surgery is the first-line choice of therapy for carotid body tumors, whereas radiotherapy is the first-line option for jugular and vagal paragangliomas.

Conclusions

Because of the complexity of clinical scenarios and treatment options for paragangliomas, a multidisciplinary algorithmic approach should be used for treating paragangliomas. The approach should emphasize single-modality treatment that yields excellent rates of tumor control, low rates of severe, iatrogenic morbidity, and the preservation of long-term function in this patient population.

Stereotactic LINAC-Radiosurgery for Glomus Jugulare Tumors: A Long-Term Follow-Up of 27 Patients

BACKGROUND

The optimal treatment of glomus jugulare tumors (GJTs) remains controversial. Due to the critical location, microsurgery still provides high treatment-related morbidity and a decreased quality of life. Thus, we performed stereotactical radiosurgery (SRS) for the treatment of GJTs and evaluated the long-term outcome.

METHODS

Between 1991 and 2011, 32 patients with GJTs underwent SRS using a linear accelerator (LINAC) either as primary or salvage therapy. Twenty-seven patients (median age 59.9 years, range 28.7-79.9 years) with a follow-up greater than five years (median 11 years, range 5.3-22.1 years) were selected for retrospective analysis. The median therapeutic single dose applied to the tumor surface was 15 Gy (range 11-20 Gy) and the median tumor volume was 9.5 ml (range 2.8-51 ml).

RESULTS

Following LINAC-SRS, 10 of 27 patients showed a significant improvement of their previous neurological complaints, whereas 12 patients remained unchanged. Five patients died during follow-up due to old age or other, not treatment-related reasons. MR-imaging showed a partial remission in 12 and a stable disease in 15 patients. No tumor progression was observed. The actuarial overall survival rates after five, ten and 20 years were 100%, 95.2% and 79.4%, respectively.

CONCLUSIONS

Stereotactic LINAC-Radiosurgery can achieve an excellent long-term tumor control beside a low rate of morbidity in the treatment of GJTs. It should be considered as an alternative therapy regime to surgical resection or fractionated external beam radiation either as primary, adjuvant or salvage therapy.

Paragangliomas: presentation and management by radiotherapy at the Prince of Wales Hospital

INTRODUCTION

Paragangliomas are commonly treated with surgery, while radiotherapy is reserved for those that are inoperable or have relapsed. However, this retrospective study aims to determine whether radiotherapy is a viable initial treatment for paragangliomas.

METHODS

Of 73 tumours researched, 44 were diagnosed and treated from January 1967 to December 2012 at the Radiation Oncology Department at the Prince of Wales Hospital and thus were eligible for analysis. Median follow-up time was 3.5 years with a range of 1 to 40 years. Thirty-four tumours were treated with radiotherapy only, and 10 tumours were treated with both surgical resection and radiotherapy. Local control and cause-specific survival were the primary end points measured.

RESULTS

Five-year local control rate for the population of 44 lesions was 89%; it was 100% in the group treated by radiotherapy alone, but only 50% in the group treated by surgery followed by radiotherapy, with radiation used for salvage. The difference in control rates between these two subset groups was found to be statistically significant (P < 0.001). Cause-specific survival rates for this eligible population at 5 and 10 years were 98% and 90%, respectively. After initial radiotherapy, 4 patients had improved cranial nerve function, there was clinical improvement in tinnitus, and one new cranial nerve deficit developed where a high dose was used.

CONCLUSIONS

Radiotherapy has high local control rates and few complications. The local control and complication rates compare favourably to surgery.

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.

Coexistence of glomangioma and yolk sac tumour in a child: a case report

Glomus tumours (GTs) primarily arise from glomus bodies that are located in the dermis layer of skin. However, they can be encountered ectopically in most parts of the body. As a result of researches done in a 17-month-old male patient who prssented to us with complaint of an increasingly growing swelling, he was diagnosed with a yolk sac tumour. Chemotherapy was started and then, he was operated. GT was found inside the tumoural mass. Our patient, who is the first case according to our knowledge, where the concurrence of yolk sac and glomus tumours was reported, has been discussed in the light of literature.

Treatment of head and neck paragangliomas with external beam radiation therapy

PURPOSE

To retrospectively assess the outcomes of radiation therapy in patients with head and neck paragangliomas.

METHODS AND MATERIALS

From 1990 to 2009, 66 patients with 81 head and neck paragangliomas were treated by conventional external beam radiation therapy in 25 fractions at a median dose of 45 Gy (range, 41.4-68 Gy). One case was malignant. The median gross target volume and planning target volume were 30 cm(3) (range, 0.9-243 cm(3)) and 116 cm(3) (range, 24-731 cm(3)), respectively. Median age was 57.4 years (range, 15-84 years). Eleven patients had multicentric lesions, and 8 had family histories of paraganglioma. Paragangliomas were located in the temporal bone, the carotid body, and the glomus vagal in 51, 18, and 10 patients, respectively. Forty-six patients had exclusive radiation therapy, and 20 had salvage radiation therapy. The median follow-up was 4.1 years (range, 0.1-21.2 years).

RESULTS

One patient had a recurrence of temporal bone paraganglioma 8 years after treatment. The actuarial local control rates were 100% at 5 years and 98.7% at 10 years. Patients with multifocal tumors and family histories were significantly younger (42 years vs 58 years [P=.002] and 37 years vs 58 years [P=.0003], respectively). The association between family predisposition and multifocality was significant (P<.001). Two patients had cause-specific death within the 6 months after irradiation. During radiation therapy, 9 patients required hospitalization for weight loss, nausea, mucositis, or ophthalmic zoster. Two late vascular complications occurred (middle cerebral artery and carotid stenosis), and 2 late radiation-related meningiomas appeared 15 and 18 years after treatment.

CONCLUSION

Conventional external beam radiation therapy is an effective and safe treatment option that achieves excellent local control; it should be considered as a first-line treatment of choice for head and neck paragangliomas.

The management of head-and-neck paragangliomas

Paragangliomas (PGLs) are tumours originating from neural crest-derived cells situated in the region of the autonomic nervous system ganglia. Head-and-neck PGLs (HNPGLs) originate from the sympathetic and parasympathetic paraganglia, most frequently from the carotid bodies and jugular, tympanic and vagal paraganglia, and are usually non-catecholamine secreting. Familial PGLs are considered to be rare, but recently genetic syndromes including multiple PGLs and/or phaeochromocytomas have been more thoroughly characterised. Nowadays, genetic screening for the genes frequently implicated in both familial and sporadic cases is routinely being recommended. HNPGLs are mostly benign, generally slow-growing tumours. Continuous growth leads to the involvement of adjacent neurovascular structures with increased morbidity rates and treatment-related complications. Optimal management mostly depends on tumour location, local involvement of neurovascular structures, estimated malignancy risk, patient age and general health. Surgery is the only treatment option offering the chance of cure but with significant morbidity rates, so a more conservative approach is usually considered, especially in the more difficult cases. Radiotherapy (fractionated or stereotactic radiosurgery) leads to tumour growth arrest and symptomatic improvement in the short term in many cases, but the long-term consequences are unclear. Early detection is essential in order to increase the chance of cure with a lower morbidity rate. The constant improvement in diagnostic imaging, surgical and radiation techniques has led to a safer management of these tumours, but there are still many therapeutic challenges, and no treatment algorithm has been agreed upon until now. The management of HNPGLs requires a multidisciplinary effort addressing the genetic, surgical, radiotherapeutic, oncological, neurological and endocrinological implications. Further progress in the understanding of their pathogenesis will lead to more effective screening and earlier diagnosis, both critical to successful treatment.

Carotid body paragangliomas: a systematic study on management with surgery and radiotherapy

The definitive universally accepted treatment for carotid body tumors (CBT) is surgery. The impact of surgery on cranial nerves and the carotid artery has often been underestimated. Alternatively, a few CBTs have been followed without treatment or irradiation. The goal of this study is to summarize the existing evidence concerning the efficacy and safety of surgery and external beam radiotherapy (EBRT) for CBT. Relevant articles were identified using strict criteria for systematic searches. Sixty-seven articles met the criteria which included 2,175 surgically treated patients. On the other hand, 17 articles including 127 patients treated with EBRT were found. Long-term control of the disease was obtained in 93.8% of patients who received surgical treatment and in 94.5% of the radiotherapy group. Surgery resulted in 483 (483/2,175 = 22.2%) new cranial nerve permanent deficits, whereas in the EBRT group, no new deficits were recorded (p = 0.004). The common/internal carotid artery was resected in 271 (12.5%) patients because of injury or tumor encasement, with immediate reconstruction in 212 (9.7%) patients. Three percent (60) of patients developed a permanent stroke and 1.3% (26) died due to postoperative complications. The major complications rates and the mortality after completion of the treatment also were significantly higher in surgical series compared to EBRT series. This systematic analysis highlights evidence that EBRT offers a similar chance of tumor control with lower risk of morbidity as compared to surgery in patients with CBT. This questions the traditional notion that surgery should be the mainstay of treatment.

Regression and local control rates after radiotherapy for jugulotympanic paragangliomas: systematic review and meta-analysis

The primary treatment goal of radiotherapy for paragangliomas of the head and neck region (HNPGLs) is local control of the tumor, i.e. stabilization of tumor volume. Interestingly, regression of tumor volume has also been reported. Up to the present, no meta-analysis has been performed giving an overview of regression rates after radiotherapy in HNPGLs. The main objective was to perform a systematic review and meta-analysis to assess regression of tumor volume in HNPGL-patients after radiotherapy. A second outcome was local tumor control. Design of the study is systematic review and meta-analysis. PubMed, EMBASE, Web of Science, COCHRANE and Academic Search Premier and references of key articles were searched in March 2012 to identify potentially relevant studies. Considering the indolent course of HNPGLs, only studies with ≥ 12 months follow-up were eligible. Main outcomes were the pooled proportions of regression and local control after radiotherapy as initial, combined (i.e. directly post-operatively or post-embolization) or salvage treatment (i.e. after initial treatment has failed) for HNPGLs. A meta-analysis was performed with an exact likelihood approach using a logistic regression with a random effect at the study level. Pooled proportions with 95% confidence intervals (CI) were reported. Fifteen studies were included, concerning a total of 283 jugulotympanic HNPGLs in 276 patients. Pooled regression proportions for initial, combined and salvage treatment were respectively 21%, 33% and 52% in radiosurgery studies and 4%, 0% and 64% in external beam radiotherapy studies. Pooled local control proportions for radiotherapy as initial, combined and salvage treatment ranged from 79% to 100%. Radiotherapy for jugulotympanic paragangliomas results in excellent local tumor control and therefore is a valuable treatment for these types of tumors. The effects of radiotherapy on regression of tumor volume remain ambiguous, although the data suggest that regression can be achieved at least in some patients. More research is needed to identify predictors for treatment success.

Stereotactic radiosurgery as the primary treatment for new and recurrent paragangliomas: is open surgical resection still the treatment of choice?

OBJECTIVE

Paragangliomas (PGs) or glomus tumors are rare, and publications comparing treatment alternatives are few. We sought to analyze our experience with stereotactic radiosurgery (SRS), review the literature, and develop treatment guidelines.

METHODS

We retrospectively examined the outcomes of 41 PGs in 36 patients treated with SRS at Stanford. Our data from medical records, telephone interviews, and imaging studies were combined with previously reported SRS data and compared to results following other treatments.

RESULTS

With a median clinical follow-up of 4.8 years (3.9 years radiographic), local control was 100%. Complications included increase in preexistent vertigo in one patient and transient cranial neuropathies in two patients. Published surgical series describe a lower local control rate as well as more frequent and severe complications. Published radiation therapy (RT) series document a slightly lower local control rate than SRS, but SRS can be delivered more quickly and conveniently. Open surgery and other combinations of treatments appear to be required for several subpopulations of PG patients.

CONCLUSIONS

We feel that SRS should be the primary treatment for most new and recurrent PGs. Even some very large PGs are appropriate for SRS. RT remains an appropriate option in some centers, especially those where SRS is not available. PGs occurring in the youngest patients, catecholamine secreting PGs, and PGs causing rapidly progressing neurologic deficits may be more appropriate for open resection. Metastatic PGs may benefit from combinations of chemotherapy and SRS or RT. Treatment guidelines are proposed.

External beam radiation therapy (EBRT) for patients with malignant pheochromocytoma and non-head and -neck paraganglioma: combination with 131I-MIBG

In patients with malignant pheochromocytoma and paraganglioma, 131I-MIBG radiotherapy can achieve an objective response rate of 30-50% with the dose limiting toxicity being hematologic. Patients with disseminated disease, who also have a few index bulky or symptomatic lesions, may benefit from the addition of targeted external beam radiotherapy alone or in combination with systemic 131I-MIBG. The records of patients with malignant paraganglioma who were treated with external beam radiotherapy at the University of Pennsylvania from February 1973 to February 2011 were reviewed in an institutional review board approved retrospective study. Of the 17 patients with tumors in the thorax, abdomen, or pelvis, 76% had local control or clinically significant symptomatic relief for at least 1 year or until death. As expected, the predominant toxicity was due to irradiation of tumor-adjacent normal tissues without clinically significant hematologic toxicity. Due to widespread systemic metastases with areas of bulky, symptomatic tumor, 5 of the 17 patients were treated with sequential 131I-MIBG (2 mCi/kg per treatment) and external beam radiotherapy to 9 sites. In these patients, all areas that were irradiated with external beam radiotherapy showed durable objective response despite all patients eventually experiencing out-of-field systemic progression requiring other treatment. Four of these patients remain alive with excellent performance status 16, 18, 23, and 24 months after external beam radiotherapy. External beam radiotherapy can be highly effective in local management of malignant paraganglioma and can be used in conjunction with 131I-MIBG due to nonoverlapping toxicities with excellent control of locally bulky tumors.

Paragangliomas and paraganglioma syndromes

Paragangliomas are rare tumors of neural crest origin. They are benign in the majority of cases and are characterized by a strong vascularisation.

In the head and neck region they most commonly occur as carotid body tumors. Jugulotympanic and especially vagal paragangliomas are seen less frequently. Complete surgical resection represents the only curative treatment option even though resection of locally advanced tumors regularly results in lesions of the lower cranial nerves and major vessels.

Appoximately 30% of all head and neck paragangliomas (HNPs) are hereditary and associated with different tumor syndromes. The paraganglioma syndromes 1, 3 and 4 (PGL 1, 3 and 4) make up the majority of those familial cases. PGL 1 is associated with mutations of the succinate dehydrogenase subunit D (SDHD) gene, PGL 3 is caused by SDHC and PGL 4 by SDHB gene mutations. Multiple HNPs and the occurance of HNPs together with pheochromocytomas are seen in SDHD as well as SDHB mutation carriers. In patients with SDHB mutations the risk for the development of malignant paraganglial tumors is significantly higher compared to SDHC and SDHD patients as well as patients with sporadic tumors. SDHC mutation carriers almost exclusively present with benign HNP that are unifocal in the majority of cases. The role of transmission is autosomal dominant for all three symptoms. Interestingly, there is a “parent-of-origin-dependent-inheritance” in subjects with SDHD gene mutations. This means that the disease phenotype may only become present if the mutation is inherited through the paternal line. We recommend screening for mutations of the genes SDHB, SDHC and SDHD in patients with HNPs. Certain clinical parameters can help to set up the order in which the three genes should be tested.

Jugular and vagal paragangliomas: Systematic study of management with surgery and radiotherapy

BACKGROUND

The definitive treatment for head and neck paraganglioma (PG) is surgical excision. Unfortunately, surgery, particularly of vagal paraganglioma (VPG; "glomus vagale") and foramen jugulare ("glomus jugulare") tumors, may be complicated by injuries to the lower cranial nerves, a high price to pay for treatment for a benign tumor. Alternatively these tumors may be followed without treatment, or irradiated. The purpose of this review was to compare the existing evidence concerning the efficacy and safety of surgery, external beam radiotherapy (EBRT), and stereotactic radiosurgery (SRS), for jugular paragangliomas (JPGs) and VPGs.

METHODS

Relevant articles were reviewed using strict criteria for systematic searches. Forty-one surgical studies met the criteria which included 1310 patients. Twenty articles including 461 patients treated with EBRT, and 14 radiosurgery studies comprising 261 patients were also evaluated. Results were compared between treatment modalities using analysis of variance (ANOVA) tests.

RESULTS

A total of 1084 patients with JPGs and 226 VPGs were treated with different surgical procedures. Long-term control of the disease was achieved in 78.2% and 93.3% of patients, respectively. A total of 715 patients with JPG were treated with radiotherapy: 461 with EBRT and 254 with SRS. Control of the disease with both methods was obtained in 89.1% and 93.7% of the patients, respectively. The treatment outcomes of a JPG treated with surgery or radiotherapy were compared. Tumor control failure, major complication rates, and the number of cranial nerve palsies after treatment were significantly higher in surgical than in radiotherapy series. The results of SRS and EBRT in JPGs were compared and no significant differences were observed in tumor control. Because only 1 article reported on the treatment of 10 VPGs with radiotherapy, no comparisons with surgery could be made. Nevertheless, the vagus nerve was functionally preserved in only 11 of 254 surgically treated patients (4.3%).

CONCLUSION

There is evidence that EBRT and SRS offer a similar chance of tumor control with lower risks of morbidity compared with surgery in patients with JPGs. Although the evidence is based on retrospective studies, these results suggest that surgery should be considered only for selected cases, but the decision should be individual for every patient.

Head and neck paragangliomas: clinical and molecular genetic classification

Head and neck paragangliomas are tumors arising from specialized neural crest cells. Prominent locations are the carotid body along with the vagal, jugular, and tympanic glomus. Head and neck paragangliomas are slowly growing tumors, with some carotid body tumors being reported to exist for many years as a painless lateral mass on the neck. Symptoms depend on the specific locations. In contrast to paraganglial tumors of the adrenals, abdomen and thorax, head and neck paragangliomas seldom release catecholamines and are hence rarely vasoactive. Petrous bone, jugular, and tympanic head and neck paragangliomas may cause hearing loss. The internationally accepted clinical classifications for carotid body tumors are based on the Shamblin Class I-III stages, which correspond to postoperative permanent side effects. For petrous-bone paragangliomas in the head and neck, the Fisch classification is used. Regarding the molecular genetics, head and neck paragangliomas have been associated with nine susceptibility genes: NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, SDHAF2 (SDH5), and TMEM127. Hereditary HNPs are mostly caused by mutations of the SDHD gene, but SDHB and SDHC mutations are not uncommon in such patients. Head and neck paragangliomas are rarely associated with mutations of VHL, RET, or NF1. The research on SDHA, SDHAF2 and TMEM127 is ongoing. Multiple head and neck paragangliomas are common in patients with SDHD mutations, while malignant head and neck paraganglioma is mostly seen in patients with SDHB mutations. The treatment of choice is surgical resection. Good postoperative results can be expected in carotid body tumors of Shamblin Class I and II, whereas operations on other carotid body tumors and other head and neck paragangliomas frequently result in deficits of the cranial nerves adjacent to the tumors. Slow growth and the tendency of hereditary head and neck paragangliomas to be multifocal may justify less aggressive treatment strategies.

Dopamine-secreting carotid body paragangliomas-biochemical control with radiotherapy

Head and neck paragangliomas that are exclusively or predominantly dopamine-secreting are rare. Surgery and/or radiotherapy are modalities for locoregional tumoral control. Little is known about the efficacy of radiotherapy for biochemical control in such tumors. We report a 62-year-old Chinese man with bilateral carotid body tumors which were exclusively dopamine secreting. The left-sided tumor invaded the skull base and encased the left carotid artery. Surgery was not performed due to high risk of morbidity and mortality. The patient received external beam radiotherapy to bilateral neck regions. Progressive decline and eventual normalization of urinary dopamine excretion was seen together with a slight reduction in tumor size. This is the first report demonstrating the efficacy of radiotherapy for both biochemical and locoregional control of functioning carotid body paragangliomas.

Radiotherapy in the management of temporal bone chemodectoma

Forty patients with 42 temporal bone chemodectomas were treated with radiotherapy alone (37 tumors) or subtotal resection and irradiation (5 tumors) at the University of Florida between 1968 and 1992. Thirty-three lesions were previously untreated, whereas 9 had undergone prior treatment (surgery, 6 lesions; radiotherapy, 1 lesion; or both, 2 lesions) and were treated for locally recurrent disease. All 3 patients who received prior radiotherapy had been treated at other institutions. Patients had minimum follow-up times as follows: 2 years, 40 patients (100%); 5 years, 31 patients (78%); 10 years, 21 patients (53%); 15 years, 16 patients (40%); 20 years, 9 patients (23%); and 25 years, 2 patients (5%). The local control rate at 20 years, calculated by the Kaplan-Meier product-limit method for the overall group of 42 lesions, was 89%. The likelihood of cause-specific survival at 20 years was 94%. The incidence of treatment-related complications was acceptable. We conclude that irradiation offers a high probability of tumor control with relatively minimal risks for patients with chemodectomas of the temporal bone.

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 Role of Radiotherapy in the Management of Paraganglioma

Paragangliomas or glomus tumors are usually low-grade hypervascular tumors occurring in various sites of the autonomic nervous system including the carotid body, glomus vagale and glomus tympanicum. Although the grading of the tumor suggests a benign clinical course, the tumor can be locally malignant and surgical management is sometimes difficult because of postoperative functional loss and local recurrence. In addition, the operative field is generally very bloody and tissue planes are not always well-defined.

Though the optimal management of paraganglioma occurs in a multidisciplinary setting, considering the excellent local control rates with primary irradiation alone, a nonsurgical definitive approach should initially be considered.

Linac-based stereotactic body radiation therapy for treatment of glomus jugulare tumors

BACKGROUND

Glomus jugulare tumors are rare, typically benign, tumors that arise from the neural crest cells that are associated with the autonomic ganglia in and around the jugular bulb. Treatment options for glomus jugulare tumors include embolization followed by resection, fractionated external beam radiation therapy (EBRT), stereotactic radiosurgery (SRS), and/or stereotactic body radiation therapy (SBRT).

MATERIALS AND METHODS

18 patients were treated with linear-accelerator based stereotactic body radiation therapy (SBRT) between May 2002 and November 2008. Fifteen patients (83%) had single glomus jugulare tumors and 3 patients had bilateral glomus jugulare tumors (although each of these patients had a single tumor targeted). The median tumor volume was 5.83 cm(3) (range, 0.32-35.47 cm(3)). Ten tumors (56%) were previously untreated, and 8 (44%) tumors were persistent after previous surgical resection. One patient had undergone previous EBRT and 2 patients were previously treated with Gamma Knife radiosurgery to the intracranial portion of their tumor, with planned SBRT to the extracranial portion 2-4 months later at our institution. The median prescribed dose was 20 Gy in 3 fractions (range: 16-25 Gy in 1-5 fx) to the 80% isodose line. The median prescription coverage of the tumor was 93.6% (range: 83-98.72%).

RESULTS

Median follow-up for the entire cohort was 22 months. All the patients were alive at the time of the last follow-up with imaging available for review. The tumor was stable in 17 patients and decreased in size in one patient--yielding a local control rate of 100%. No patients experienced any new or worsening treatment-related neurologic deficits.

CONCLUSIONS

SBRT is a safe and efficacious treatment modality for glomus jugulare tumors.

Paraganglioma of the head and neck: long-term local control with radiotherapy

OBJECTIVES

Paragangliomas are rare neuroendocrine neoplasms of the head and neck. Treatment strategies include resection, definitive external beam radiation therapy (EBRT), stereotactic radiosurgery (SRS), or observation alone. Due to their rarity and indolent clinical behavior, the optimal management for long-term control is unknown.

METHODS

This Institutional Review Board-approved retrospective study identified all paragangliomas of the head and neck treated with definitive fractionated radiotherapy at Duke University Medical Center from 1963 to 2005 with minimum 2-year follow-up. Local control (LC) was calculated using the Kaplan-Meier method.

RESULTS

Thirty-one patients were identified and treated with EBRT (median dose: 54 Gy, range: 38-65 Gy). Twelve patients were treated with megavoltage photon; 19 were treated with either cobalt-60 or cesium-137. Fourteen (45%) had undergone resection preceding radiation. Median follow-up was 9 years (range: 2-35 years), with 10 patients having greater than 15-year follow-up. LC at 5, 10, and 15 years was 96%, 90%, and 90%, respectively. There were no failures in the group treated with megavoltage photons, although this was not statistically significant (P = 0.28). There was no difference in LC between salvage radiation therapy (RT) used after surgical failure and definitive RT alone (10-year LC, 73% vs. 100%, respectively, P = 0.31). The incidence of acute toxicity greater than grade 2 was 3%, and there were no late toxicities greater than grade 2.

CONCLUSIONS

RT is an effective and well-tolerated treatment for paragangliomas of the head and neck.

Clinical and pathological analysis of malignant carotid body tumour: a report of nine cases

CONCLUSIONS

Malignant carotid body tumour (MCBT) is a clinically rare disease that often invades the carotid artery and cranial nerves. Diagnosis of malignant tumour should be based on extensive invasion of neighbouring organs and distant metastasis. Extensive resection should be undertaken early. Radiotherapy is effective, whereas chemotherapy is uncertain.

OBJECTIVE

To summarize the clinical pathological and prognostic characteristics of MCBT and explore methods for diagnosis and treatment.

MATERIALS AND METHODS

The study material comprised clinical, pathological, therapeutic and follow-up data concerning nine patients (four males, five females) with MCBT, treated at Tianjin Cancer Hospital between January 1956 and June 2006. The material was analysed retrospectively. Disease duration averaged 6.4 years. Shamblin classification was: one case, type II; 8 cases, type III. All nine patients underwent ultrasound examination, four underwent digital subtraction arteriography (DSA) and three had magnetic resonance angiography (MRA). Five patients underwent preoperative training of compression of the carotid (Matas test). Extensive resection was performed in all nine cases.

RESULTS

The carotid artery was blocked in three patients. In one of these the artery was reconstructed with a vascular prosthesis, while two underwent carotid ligation. Eight patients suffered from a cranial nerve dysfunction (defect) and two suffered postoperatively from a hoarse voice, four had a glossal deviation, five had Horner's syndrome and one had a deviation of the lip angle. One patient had a congestive cough. The histopathological diagnosis in all nine cases was MCBT. One patient had metastases to a cervical lymph node and lung and another had liver metastasis. The median follow-up period was 3 years (range 6 months to 14 years). Six patients survived surgery, of whom two underwent radiotherapy. Two patients died and one could not be traced.

Definitive radiotherapy in the management of paragangliomas arising in the head and neck: a 35-year experience

BACKGROUND

An evaluation of the treatment results for 104 patients with 121 paragangliomas of the temporal bone, carotid body, and/or glomus vagale who were treated with radiation therapy (RT) at the University of Florida between 1968 and 2004.

METHODS

Eighty-nine paragangliomas (86%) were treated with conventional megavoltage techniques, 15 (14%) patients with stereotactic fractionated radiation therapy, 6 (6%) patients with stereotactic radiosurgery (SRS), and 11 (11%) patients with intensity-modulated radiation therapy (IMRT).

RESULTS

There were 6 local recurrences. One recurrence was salvaged with additional RT. The actuarial local control and cause-specific survival rates at 10 years were 94% and 95%. The overall local control rate for all 121 lesions was 95%; the ultimate local control rate was 96%. The incidence of treatment-related complications was low.

CONCLUSION

Fractionated RT offers a high probability of tumor control with minimal risks for patients with paragangliomas of the temporal bone and neck.

Carotid chemodectomas: long-term results of subadventitial resection with deliberate external carotid resection

The aim of this study was to evaluate the short-term and long-term results of the subadventitial resection of carotid chemodectomas and to validate the importance of deliberate resection of the external carotid artery (ECA). From 1981 to 2006, 39 carotid chemodectomas of the carotid bifurcation or of the neighboring nerves were operated on in our department. There were 14 men and 22 women, with a mean age 44.4 +/- 5 (range 21-78) years. One of these operations was a redo surgery for local recurrence. One female patient presented with a bilateral tumor. Two tumors were secreting catecholamines. All these tumors affected the carotid body; 10 of them were also affecting the vagus nerve, and one among these last 10 affected the sympathetic nerve as well. In 11 cases, the tumor had spread into the subparotidal space and, in one case, into the skull. In two cases, the tumor had been revealed by hemispheric ischemia and in every case by tumoral syndrome. All the patients were followed up by clinical examination, duplex scan, or computed tomographic scan until the end of 2006. In 38 cases, complete resection was performed; an incomplete resection was performed in one case with cranial invasion. Under general anesthesia, and most of the time without pharmaceutical preparation, surgery consisted of a deliberate sacrifice of the ECA followed by subadventitial resection of the tumor. In one case, a previous embolization had been carried out to facilitate the cleavage, which in fact rendered it more complicated. In 22 cases, resection concerned the ECA; in seven cases, it concerned the common carotid artery and the internal carotid artery (ICA): in seven cases the superior laryngeal nerve, in nine cases the vagus nerve, in five cases the sympathetic nerve, and in four cases the jugular vein. In 13 cases, node clearing was associated. In 20 cases, an additional vascular procedure was performed: nine dilatations for spasm of the ICA, five autogenous vein grafts, two prosthetic bypasses, and one endarterectomy associated with a patch angioplasty. All patients were followed up until 2006. At 3 months, the observed complications were the sequelae of a homolateral hemispheric accident due to thrombosis of a vein graft, eight peripheral facial nerve palsies, 12 vocal palsies, seven Claude Bernard-Horner (CBH) syndromes, eight palatal paralyses, and 10 nociceptive pains. Some of these complications did persist: nine vocal cord paralyses that were successfully treated by speech therapy, three mild CBH syndromes, and nociceptive pains in 6% of the cases (15.4%), incapacitating in one case. With a follow-up of 115 +/- 27 (range 1-298) months, three local recurrences were recorded at 6 and 10 years. In two cases, local recurrence occurred when initial resection of the ECA had not been performed. Two patients presented with a contralateral lesion, at 12 and 16 years, respectively. At 40 months, one patient had to be reoperated on for an atheromatous stenosis. At 51 months, a female patient's death was not related to the operation. Subadventitial resection of carotid body tumors with deliberate resection of the ECA is a simple and efficient procedure. It is the preferential treatment for these slow-growing localized tumors.

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.

Radiosurgery for glomus jugulare tumors: experience treating 16 patients in Iran

Object

Glomus jugulare tumors (GJT) have traditionally been treated by surgery or fractionated external-beam radiotherapy. The aim of this retrospective study was to determine the tumor control rate, clinical outcome, and short-term complications of stereotactic radiosurgery in subsets of patients who are poor candidates for these procedures, based on age, medical problems, tumor size, or prior treatment failure.

Methods

The Leksell Gamma Knife was used to treat 16 patients harboring symptomatic, residual, recurrent, or unresectable GJTs. The age of the patients ranged from 12 to 77 years (median 46.5 years). Gamma Knife surgery (GKS) was performed as primary treatment in five patients (31.3%). Microsurgery preceded radiosurgery in 10 patients (62.5%) and fractionated radiotherapy in three patients (18.8%). The median tumor volume was 9.8 cm3 (range 1.7–20.6 cm3). The median marginal dose applied to a mean isodose volume of 50% (range 37–70%) was 18 Gy (range 14–20 Gy).

Neurological follow-up examinations revealed improved clinical status in 10 patients (62.5%), a stable neurological status in six (37.5%), and no complications. After radiosurgery, follow-up imaging was conducted in 14 patients; the median interval from GKS to the last follow up was 18.5 months (range 4–28 months). Tumor size had decreased in six patients (42.9%), and the volume remained unchanged in the remaining eight (57.1%). None of the tumors increased in volume during the observation period.

Conclusions

According to the authors' experience, GKS represents a useful therapeutic option to control symptoms and may be safely conducted in patients with primary or recurrent GJTs with no death and no acute morbidity. Because of the tumor's naturally slow growth rate, however, long-term follow-up data are needed to establish a cure rate after radiosurgery.

Carotid body paraganglioma. Diagnosis and treatment by angiography

Paraganglioma is a rare neoplasia of neural crest origin. It most commonly arises in carotid body, jugular bulb, tympanic plexus on the promontory, and along the vagal nerve pathway or anywhere along the paraganglia pathway. This review describes our experience of cervical paraganglioma. Although there is no consensus in the literature on preoperative angiographic embolization, we think angiography is the gold standard in the diagnosis and treatment of paraganglioma. A small paraganglioma probably does not usually require preoperative embolization because the risks may exceed the benefits. But angiography is mandatory in the diagnosis and treatment of large highly vascular paragangliomas. Imaging of the vascular map of the tumor, that is only possible by angiography, will help the neurosurgeon evaluate the real extension of the neoplasia and chose treatment modalities. Embolization is performed to decrease operative bleeding, shorten the surgery timing and avoid cranial nerve deficit. Cemal Umit Isik et al. studied four brothers with familial paragangliomas noting unexplained concomitant thyroid functional disorders in their patients. Because of the pedigree they thought this may have been a coincidence. Our reported case, unrelated to the Turkish family, also had hypothyroidism suggesting that the relation between paraganglioma and thyroid dysfunction may not be merely a coincidence.

Long-term results of irradiation for paraganglioma

PURPOSE

The management of paragangliomas is controversial. Observation, surgery, external-beam radiotherapy (EBRT), and stereotactic radiosurgery (SRS) may, alone or in combination, be appropriate, depending on the size and extent of the tumor, previous treatment, and patient age, general health, and neurologic condition. Few data exist regarding long-term tumor control and late effects after EBRT or SRS.

METHODS AND MATERIALS

We performed a retrospective review of all patients treated with EBRT or SRS for paraganglioma at our institution between 1967 and 1994. The endpoints of the study were tumor control and late complications.

RESULTS

The 33 patients in this study had a median follow-up of 13 years (range, 4 months to 36 years). The 10-year tumor control rate was 92% (95% confidence interval, 75-98%). At the last follow-up visit, no patient had developed a radiation-induced malignancy.

CONCLUSION

External-beam RT and SRS are safe and effective for enlarging and/or symptomatic paragangliomas. The risk of developing a delayed radiation-induced malignancy after EBRT or SRS is low. This risk must be weighed against the significant immediate and permanent risk of cranial nerve deficits if the tumor is untreated or is surgically resected. This risk must also be weighed against the immediate but low risk of surgical mortality.

Less Common Indications for Stereotactic Radiosurgery or Fractionated Radiotherapy for Patients with Benign Brain Tumors

Microsurgical resection remains the mainstay of treatment for truly benign brain tumors that can be safely resected because of the potential for permanent cure with most histologic findings, including most of the histologic findings discussed in this article. Physicians must keep in mind the indolent nature of many of the benign brain tumors and realize that many patients are likely to live out normal life spans if tumor control is achieved. Therefore, it is not sufficient simply to consider local tumor control rates and short-term toxicity risks when choosing between surgery, stereotactic radiosurgery, and fractionated radiotherapy. Patients need to be apprised of all therapeutic options and to make their decisions with all information required to evaluate the risks and benefits. For benign brain tumors, these decisions may have consequences that last for decades.

Glomus tumour in a child

Glomus tumours are uncommon neoplasms. Very rarely do they present in the paediatric age group. We describe a case of bilateral glomus tumours in a 13-year-old girl that were successfully treated with radiotherapy. The patient remains well 8 years after completion of treatment.

Treatment of Glomus Jugulare Tumors in Patients with Advanced Age: Planned Limited Surgical Resection Followed by Staged Gamma Knife Radiosurgery: A Preliminary Report

OBJECTIVE

To minimize treatment comorbidities in glomus jugulare tumor patients with advanced age while reducing pulsatile tinnitus and preserving or improving residual hearing using a limited middle ear/mastoid tumor resection and postoperative gamma knife radiosurgery to tumor remnants in the jugular foramen region.

STUDY DESIGN

Retrospective consecutive case review of five patients.

SETTING

Tertiary referral, academic medical center.

PATIENTS

Patients with advanced age (mean, 69.6 yr; range, 61-78 yr) harboring symptomatic glomus jugulare tumors.

INTERVENTION

All patients were treated with resection of middle ear and mastoid portions of tumor and subsequent gamma knife radiosurgery to jugular foramen portion of tumor.

MAIN OUTCOME MEASURES

Length of hospitalization; hearing, pulsatile tinnitus, cranial nerve, and tumor control status.

RESULTS

All patients were treated on an outpatient surgical basis without the need for blood transfusion. There were no incidents of a change in cranial nerve status (Cranial Nerves VII, IX, X, XI, and XII) in the immediate postoperative period. All patients had improvement or resolution of pulsatile tinnitus with preservation or improvement of preoperative hearing levels. Tumor volume was stable or reduced in all patients at mean follow-up of 19 months (range, 11-24 mo). Gamma knife radiosurgery (mean peripheral dose of 15 Gy) was not associated with any significant immediate or delayed complications.

CONCLUSION

Short-term data reveals that staged microsurgical and radiosurgical therapy for glomus jugulare tumors in the symptomatic patient with advanced age is safe and yields favorable results regarding tinnitus, hearing, and cranial nerve status. Long-term data are needed to further evaluate the effectiveness of this treatment algorithm before extrapolating this treatment option to younger patients.

Paragangliomas of the head and neck: diagnosis and treatment

Paragangliomas of the head and neck (HNP) represent rare tumors of neural crest origin. They are highly vascular neoplasms that are benign in the majority of cases. The site of origin defines the name given those tumors. In the head and neck, they most commonly occur at the carotid bifurcation, where they are referred to as carotid body tumors (CBT). Other common sites of origin are the jugular bulb (jugular paraganglioma; JP), the tympanic plexus on the promontory (tympanic paraganglioma; TP) and the vagal nerve (vagal paraganglioma; VP). Patients with cervical paragangliomas frequently present with a painless, slowly enlarging mass in the lateral neck. In many patients with TP and JP, tinnitus and hearing loss are early symptoms. JP patients often suffer from lower cranial nerve deficits. Evaluation by an imaging modality is necessary to establish the diagnosis. Imaging procedures frequently used include B-mode sonography with color-coded Doppler sonography, computed tomography (CT), magnetic resonance imaging (MRI) and digital substraction angiography (DSA). Debate exists in the literature regarding the different treatment modalities for paragangliomas which include surgery, radiotherapy and stereotactic radiosurgery. The role of preoperative angiography and embolization has also been a matter of discussion. The diagnostic work up and the different treatment options for patients with head and neck paragangliomas will be presented and discussed.

Gamma knife surgery for glomus jugulare tumors: an intermediate report on efficacy and safety

OBJECT

Glomus jugulare tumors are rare tumors that commonly involve the middle ear, temporal bone, and lower cranial nerves. Resection, embolization, and radiation therapy have been the mainstays of treatment. Despite these therapies, tumor control can be difficult to achieve particularly without undo risk of patient morbidity or mortality. The authors examine the safety and efficacy of gamma knife surgery (GKS) for glomus jugulare tumors.

METHODS

A retrospective review was undertaken of the results obtained in eight patients who underwent GKS for recurrent, residual, or unresectable glomus jugulare tumors. The median radiosurgical dose to the tumor margin was 15 Gy (range 12-18 Gy). The median clinical follow-up period was 28 months, and the median period for radiological follow up was 32 months. All eight patients demonstrated neurological stability or improvement. No cranial nerve palsies arose or deteriorated after GKS. In the seven patients in whom radiographic follow up was obtained, the tumor size decreased in four and remained stable in three.

CONCLUSIONS

Gamma knife surgery would seem to afford effective local tumor control and preserves neurological function in patients with glomus jugulare tumors. If long-term results with GKS are equally efficacious, the role of stereotactic radiosurgery will expand.

Gamma knife surgery for glomus jugulare tumors: an intermediate report on efficacy and safety

Object. Glomus jugulare tumors are rare tumors that commonly involve the middle ear, temporal bone, and lower cranial nerves. Resection, embolization, and radiation therapy have been the mainstays of treatment. Despite these therapies, tumor control can be difficult to achieve particularly without undo risk of patient morbidity or mortality. The authors examine the safety and efficacy of gamma knife surgery (GKS) for glomus jugulare tumors.

Methods. A retrospective review was undertaken of the results obtained in eight patients who underwent GKS for recurrent, residual, or unresectable glomus jugulare tumors. The median radiosurgical dose to the tumor margin was 15 Gy (range 12–18 Gy). The median clinical follow-up period was 28 months, and the median period for radiological follow up was 32 months.

All eight patients demonstrated neurological stability or improvement. No cranial nerve palsies arose or deteriorated after GKS. In the seven patients in whom radiographic follow up was obtained, the tumor size decreased in four and remained stable in three.

Conclusions. Gamma knife surgery would seem to afford effective local tumor control and preserves neurological function in patients with glomus jugulare tumors. If long-term results with GKS are equally efficacious, the role of stereotactic radiosurgery will expand.

Management of paragangliomas. Clinical and angiographic aspects

SUMMARY

Head and neck paragangliomas are highly vascular tumors with variable clinical behavior. The goal of this paper is to determine specific clinical and radiological findings and extract from these findings a treatment algorithm. Twenty-three patients with paragangliomas were referred from different surgical centers for angiography and pre-operative embolization. Clinical records were analyzed retrospectively, and focused on impairment of cranial nerves. Angiographic features of paragangliomas, such as arterial supply, tumor flow characteristics, and venous drainage, were evaluated to find characteristic angioarchitectural patterns. All but one patient presented with a single tumor. All eight jugular and four of five vagal paragangliomas caused a lower cranial nerve deficit. Tympanic paragangliomas presented with hearing loss and tinnitus. The ascending pharyngeal artery was the main feeder and contributed to the supply in every tumor. Jugular and vagal paragangliomas typically compromise the patency of the jugular vein with resulting antegrade or retrograde flow through collateral venous systems. Surgical resection of vagal and jugular paragangliomas was especially performed when unifocal paragangliomas were present. In all of these patients, the tumor caused a cranial nerve deficit. The supply from an enlarged ascending pharyngeal artery is typical for paragangliomas. The venous drainage pattern of jugular and vagal paragangliomas allows differentiation from other vascular lesions at the skull base.

Fractionated stereotactic conformal radiotherapy in the management of large chemodectomas of the skull base

PURPOSE

To evaluate the role of fractionated stereotactic conformal radiotherapy (FSRT) as a noninvasive method in the management of large chemodectomas of the skull base.

METHODS AND MATERIALS

Twenty-two patients with chemodectomas of the skull base were treated with FSRT at our institution. Ten patients received primary RT, and 12 patients were treated for recurrent or progressive disease after primary surgery (8 patients) or embolization (4 patients). The median total dose was 57.6 Gy, with a median of 1.8 Gy/fraction. The median target volume was 71.8 cm3 (range, 10.5-212.2 cm3). The most common symptoms at the initial diagnosis were pulsatile tinnitus (16 patients), hearing loss (14 patients), and balance disturbance (14 patients). Twelve patients had additional cranial nerve deficits.

RESULTS

The median follow-up was 5.7 years (range, 19-177 months). The actuarial overall survival rate was 89.5% at 5 and 10 years. The actuarial local control rate was 90.4% at 5 and 10 years. Seven patients (32%) had a partial response and 13 (59%) had stable disease of the irradiated chemodectoma. Two symptomatic patients developed recurrence after 19 and 32 months. Neurologic dysfunction improved or completely resolved in 59% and stabilized in 32%; 9% of patients experienced impairment of preexisting neurologic dysfunction. No patient developed new neurologic deficits after FSRT. RT was interrupted in 1 patient because of a maxillary bone abscess. In all other patients, no acute or late adverse reactions greater than Common Toxicity Criteria Grade 2 were seen.

CONCLUSION

Fractionated stereotactic conformal radiotherapy is an effective and well-tolerated noninvasive treatment for chemodectomas, with excellent tumor control rates and a low risk of morbidity. It is an option for patients at greater risk of microsurgical resection or with residual and recurrent tumors.

The role of Gamma Knife radiosurgery in the management of glomus jugular tumours

BACKGROUND

Glomus jugular tumours are usually managed by microsurgical resection and/or radiotherapy with considerable risk for treatment-related morbidity. The role of Gamma Knife Radiosurgery (GKRS) in the management of these lesions remains to be defined.

METHOD

Between May 1992 and November 2000, 19 patients with glomus tumours underwent GKRS at our department. Nine patients received radiosurgery for residual or recurrent paragangliomas following microsurgical resection and in 10 cases GKRS was performed as primary treatment. The median tumour volume was 5.22 ccm (range: 0.38-33.5 ccm). Marginal doses of 12-20 Gy (median 14 Gy) were applied to enveloping isodose volume curves (Range: 30-55%, median 50%).

FINDINGS

Except for an 81-year-old patient who died 9 months after radiosurgery the observation time ranged from 1.5 to 10 years (median 7.2 yrs). The total tumour control rate was 94.7% (7 cases with decreased and 11 with stable tumour size). The only patient with tumour progression (5.3%) underwent repeated radiosurgical treatment 85 months after initial GKRS. A newly diagnosed second lesion in the cavernous sinus was treated radiosurgically as well 53 months after the first Gamma Knife procedure. On clinical examination 10 patients (52.6%) presented with improved and 8 patients (42.1%) with unchanged neurological status. Deterioration in one patient (5.3%) was not related to tumour or radiosurgery.

INTERPRETATION

As GKRS demonstrated to be a minimally invasive treatment alternative to microsurgery and radiotherapy with no acute or chronic toxicity it should be considered more frequently in the primary or adjuvant strategy for glomus jugular tumours.

Does Catecholamine Secretion from Head and Neck Paragangliomas Respond to Radiotherapy? Case Report and Literature Review

We report a 38-year-old woman with a malignant catecholamine-secreting vagal paraganglioma. In the preceding year she had intermittent severe frontoparietal headaches. While she was receiving radiotherapy (35 Gy in 15 fractions) she developed palpitations, which steadily worsened over the following three years. A repeat CT scan showed no change in the size of the tumor. Urinary catecholamines were elevated and a MIBG scan showed increased uptake in the region of the vagal paraganglioma. She underwent near total resection of her tumor via a Fisch type C approach. Pathological examination showed a paraganglioma with metastasis involving a cervical lymph node. The palpitations and headaches resolved completely after surgery. This report and other published case reports suggest that catecholamine secretion from head and neck paragangliomas does not appear to respond to radiotherapy. Patients with cardiovascular symptoms from catecholamine-secreting paragangliomas are best managed surgically.

New therapeutic and surgical approaches for sporadic and hereditary pheochromocytoma

Pheochromocytoma is a rare, surgically correctable cause of hypertension. Modern medical blockade has significantly improved patient survival and morbidity. The last decade has seen the identification of the genes responsible for several hereditary causes of pheochromocytoma. Evaluation of these patients has demonstrated different catecholamine profiles associated with the different syndromes. Genetic testing and new, more sensitive catecholamine tests are allowing better, earlier diagnosis of affected patients. Some patients with small tumors deemed nonfunctional by traditional methods may be safely observed until function is demonstrated. Laparoscopic surgery has supplanted the use of open surgery in the management of these tumors. Adrenocortical-sparing surgery may be performed using laparoscopy in patients with hereditary forms of pheochromocytoma.