Radiosurgery for paraganglioma of the temporal bone

Long term outcomes with linear accelerator stereotactic radiosurgery for treatment of jugulotympanic paragangliomas

BACKGROUND

Data supporting linear accelerator (linac) stereotactic radiosurgery (SRS) for jugulotympanic paragangliomas (JTPs) come from small series with minimal follow-up. Herein, we report a large series of JTPs with extended follow-up after frameless linac-based SRS.

METHODS

JTPs treated with linac-based SRS from 2002 to 2019 with 1+ follow-up image were reviewed for treatment failure (radiographic or clinical progression, or persistent symptoms after SRS requiring intervention) and late toxicities (CTCAE v5.0).

RESULTS

Forty JTPs were identified; 30 were treated with a multifraction regimen. Median clinical and radiographic follow-up was 79.7 (interquartile range [IQR] 31.7-156.9) and 54.4 months (IQR 17.9-105.1), respectively, with a median 4.5 follow-up scans (IQR 2-9). Seven-year progression-free survival (PFS) was 97.0% (95% confidence interval 91.1%-100.0%). PFS was similar between single- and multifraction regimens (log rank P = .99). Toxicity was seen in 7.7% (no grade III).

CONCLUSIONS

With extended clinical and radiographic follow-up, frameless linac-based SRS provides excellent local control with mild toxicity <8%.

LINAC radiosurgery for glomus jugulare tumors: retrospective - cohort study of 23 patients

BACKGROUND

Glomus jugulare tumors (GJTs) are uncommon and locally disruptive tumors that usually arise within the jugular foramen of the temporal bone. Surgery was the treatment of choice up until recently. In the last decades, however, radiosurgery has surfaced as a promising alternative treatment by providing excellent tumor control with low risk of cranial nerve injuries. Our aim was to examine the results of radiosurgery specifically, linear accelerator stereotactic radiosurgery (LINAC SRS) for GJT treatment. We hypothesized that radiosurgery will reduce the size of the tumor and improve neurological symptoms.

DESIGN AND METHOD

Between January 1, 1994 and December 31, 2013, 30 patients with GJTs were treated in Sheba Medical Center using LINAC SRS treatment. Comprehensive clinical follow-up was available for 23 patients. Sixteen patients were female and seven males with a median age of 64 years, with a range of 18-87 years. In 19 of the patients, LINAC SRS was the primary treatment, whereas in the remaining four cases, surgery or embolization preceded radiosurgery. The median treated dose to tumor margin was 14 Gy (range 12-27 Gy), and the median tumor volume before treatment was 5 ml (range 0.5-15 ml).

RESULTS

Following the LINAC SRS treatment, 14 of 23 patients (60%) showed improvement of previous neurological deficits, nine patients (40%) remained unchanged. At the end of a follow-up, tumor reduction was seen in 13 patients and a stable volume in eight (91% tumor control rate). Two cases of tumor progression were noted. Three patients (13%) had post- SRS complications during the follow-up, two of which achieved tumor control, while in one the tumor advanced.

CONCLUSIONS

LINAC SRS is a practical treatment option for GJTs, with a high rate of tumor control and satisfactory neurological improvement.

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.

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.

Stereotactic radiosurgery for the treatment of Glomus Jugulare Tumors

BACKGROUND

The glomus jugulare tumor is a slowly growing benign neoplasm originating from neural crest. There is a high morbidity associated with surgical resection of glomus jugulare. Radiosurgery play a relevant role as a therapeutic option in these tumors and its use has grown in popularity. The authors describe a retrospective series of 15 patients and reviewed the literature about the glomus jugulare tumors.

METHODS

We reviewed retrospectively the data of 15 patients treated with stereotactic linear accelerator stereotactic radiosurgery (LINAC) radiosurgery between 2006 and 2011.

RESULTS

The average tumor volume was 18.5 cm(3). The radiation dose to the tumor margin ranged between 12 and 20 Gy. The neurological status improved in three patients and remained unchanged in 12 patients. One patient developed a transient 7(th) nerve palsy that improved after clinical treatment. All tumors remained stable in size on follow-up with resonance magnetic images.

CONCLUSIONS

The radiosurgery is a safe and effective therapy for patients with glomus jugulare tumor. Despite the short follow-up period and the limited number of patients analyzed, we can infer that radiosurgery produce a tumor growth control with low morbidity, and may be used as a good option to surgical resection in selected cases.

Our experience with carotid body paragangliomas

Carotid body paragangliomas (CBP) are rare neoplasms arising from the small chemoreceptor organ in the adventitia of the common carotid bifurcation. The aim of this study is to present the diagnostic process, performed treatment and obtained results in patients with carotid body paragangliomas of the Department of Otolaryngology of Istanbul Education and Research Hospital between March 1997 and November 2008. Retrospective analysis was carried out, based on the medical documentation of 5 patients with carotid body paragangliomas (3 women and 2 men), age range 44 to 68 years with a mean of 59.6 years. Four of the patients were diagnosed and treated with Shamblin type II tumor, one of the patients with type I. Physical examination, radiological evaluation, method of the treatment and post-treatment complications were studied. The most common and single symptom was nonspecific neck mass. Preoperative diagnostic evaluation consisted of a color duplex ultrasonography, computerized tomography with contrast enhancement, magnetic resonance imaging and digital subtraction angiography. In all patients with Shamblin type I and II, blunt dissection of the tumor was conducted smoothly in the subadventitial plane. Postoperative vagus nerve and hypoglossal nerve deficit were reported in one case. Carotid body paraganglioma excision has higher risk of cranial nerve paresis and carotid artery injury, so it requires careful handling and good surgical skills to ensure complete removal.

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.

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.

Radiosurgery of glomus jugulare tumors: a meta-analysis

PURPOSE

During the past two decades, radiosurgery has arisen as a promising approach to the management of glomus jugulare. In the present study, we report on a systematic review and meta-analysis of the available published data on the radiosurgical management of glomus jugulare tumors.

METHODS AND MATERIALS

To identify eligible studies, systematic searches of all glomus jugulare tumors treated with radiosurgery were conducted in major scientific publication databases. The data search yielded 19 studies, which were included in the meta-analysis. The data from 335 glomus jugulare patients were extracted. The fixed effects pooled proportions were calculated from the data when Cochrane's statistic was statistically insignificant and the inconsistency among studies was <25%. Bias was assessed using the Egger funnel plot test.

RESULTS

Across all studies, 97% of patients achieved tumor control, and 95% of patients achieved clinical control. Eight studies reported a mean or median follow-up time of >36 months. In these studies, 95% of patients achieved clinical control and 96% achieved tumor control. The gamma knife, linear accelerator, and CyberKnife technologies all exhibited high rates of tumor and clinical control.

CONCLUSIONS

The present study reports the results of a meta-analysis for the radiosurgical management of glomus jugulare. Because of its high effectiveness, we suggest considering radiosurgery for the primary management of glomus jugulare tumors.

Paragangliomas of the Head & Neck: the KMC experience

To determine the clinical features, investigations, intra-operative findings, surgical approaches used and the results of the treatment for paragangliomas of the head and neck. Retrospective study of 14 cases of paragangliomas in head and neck seen over a period of 10 years including five carotid body tumors, seven glomus jugulares and two glomus tympanicums. HRCT scans and bilateral carotid angiography were done in all cases of glomus jugulare. Pre-operative embolization was done in most cases. The trans-cervical approach was used for all cases of carotid body. In three cases of Type B jugulare tumors, a post-aural tympanotomy was used. A Fisch Type A approach was done for three cases of Type D jugulare tumors. Postaural tympanotomy approach was used for both patients with glomus tympanicum. In one case of extratympanic glomus jugulare tumor with hypoglossal palsy, a neck exploration was done to isolate and excise the tumor. Five patients with carotid body tumors presented as unilateral, painless, pulsatile swelling in the upper neck. Intra-operatively, three of the tumors were classified into Shamlin's Grade II and one each into Grade III and Grade I. A carotid blow-out occurred in one of the patients with Grade II disease, which was managed. ECA resection had to be done in one case. Seven patients were diagnosed to have glomus jugulare and two with glomus tympanicum. Six glomus jugulare tumors presented with hearing loss, ear discharge and obvious swelling. Glomus tympanicums presented with hearing loss but no bleeding from the ear. On examination, tumors presented with an aural polyp with no VII nerve deficits. Both tympanicums were classified as Fisch Type A, three of the jugulares classified as Type B, two as Type D2 and one as Type D1. Tumors were found to be supplied predominantly by the ascending pharyngeal artery. In three cases of Type B jugulare tumors, a post-aural tympanotomy was used. A Fisch Type A approach was done for three cases of Type D jugulare. The transcanal approach was used for both patients with glomus tympanicum. Paragangliomas are uncommon tumors that need accurate diagnosis and skilled operative techniques. Though the surgical approaches may appear complicated, the removal provides good cure rates with minimal morbidity and recurrence. Lateral skull base approaches should be the armamentarium of every head and neck surgeon.

[Unilateral tongue atrophy and articulation difficulties]

A 24-year-old female complained of difficulty articulating and chewing of 2 more than weeks' standing. She reported that her tongue felt "heavy and inert". Clinically, right-sided atrophy of the tongue and deflection of the tongue to the right were observed. Tone audiogram demonstrated normal hearing on both sides and tympanometry was also normal. On CT, a bone-destroying process was seen in the area of the right lateral skull base, which reached as far as the internal carotid artery. MRI demonstrated atrophy of the right tongue musculature with fatty degeneration, as well as an oval, smoothly edged lesion which showed marked contrast-medium uptake with a "salt and pepper" configuration in the region of the right jugular foramen. The diagnosis was hypoglossal paresis due to ipsilateral jugular paraganglioma (Fisch classification C1). Following embolization of the feeding vessels of the paraganglioma, the tumor was completely resected, including the hypoglossal nerve which ran through the tumor. Postoperative dysfunction of the vagus and facial nerves became unsymptomatic with time as a result of logopedic therapy.

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.

Irradiation of glomus jugulare tumors: a historical perspective

Glomus jugulare tumors are rare, slow-growing vascular lesions that arise from the chief cells of the paraganglia within the jugular bulb. They can be associated with the tympanic branch of the glossopharyngeal nerve (Jacobsen nerve) or the auricular branch of the vagus nerve (Arnold nerve) and are also referred to as chemodectomas or nonchromaffin paragangliomas. Optimal treatment of these histologically benign tumors remains controversial. Surgery remains the treatment of choice, but can carry high morbidity rates. External-beam radiation was originally used for subtotal resections and in patients who were poor surgical candidates; however, radiosurgery has recently been introduced as an effective and safe treatment option for patients with these tumors. In this article the authors discuss the history of radiation therapy for glomus jugulare tumors, focusing on recent radiosurgical results.

Radiosurgery for glomus jugulare tumors

Results for treating glomus jugulare tumors with radiosurgery have been limited by short follow-up and small number of patients. We report our experience using LINAC or CyberKnife in 21 tumors with a median follow-up of 66 months (Mean follow-up of 60 months). In addition, we have a subset of eight patients that were followed out for more than 10 years. Patients were treated with doses ranging from 1400 cGy to 2700 cGy. We retrospectively assessed patients for efficacy and post treatment side effects. All patients had stable neurological symptoms, and two patients experienced transient ipsilateral tongue weakness and hearing loss, both of which subsequently resolved. One patient experienced transient ipsilateral vocal cord paresis; however, this patient received previous external beam radiotherapy. All tumors remained stable or decreased in size by MRI exam. Our results support radiosurgery as an effective and safe method of treatment for glomus jugulare tumors with low morbidity as evidenced by a larger number of patients and long term follow-up.

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.

Intracranial glomus jugulare tumors: volume reduction with Gamma Knife surgery

Object

Glomus jugulare tumors (GJTs) are slow-growing benign tumors arising from paraganglion cells of the superior vagal ganglion. Involvement of cranial nerves and extensive erosion of the jugular foramen and petrous bone are typically seen in patients with GJTs. Advances in microsurgical techniques have improved patient outcomes, but tumors involving the petrous bone remain difficult to treat effectively. The aim of our study was to further evaluate the role of Gamma Knife surgery (GKS) in the management of intracranial GJTs.

Methods

Twelve consecutive patients (mean age 51.7 years) with intracranial GJTs were included in this study. The treatment strategy was either multimodal, with microsurgical tumor volume reduction followed by GKS in patients suffering from brainstem compression, or GKS as the only treatment. Follow-up examinations included thorough neurological examinations and neuroradiological quantitative volumetric tumor analysis. Five patients (41.6%) underwent microsurgery before GKS. Tumor volumes ranging from 1.6 to 24.8 cm3 were treated using prescription doses of 14 to 20 Gy (nine–28 isocenters). The achieved overall tumor control rate after GKS was 100% (33 months mean follow up) with only mild side effects observed. A tumor volume reduction (mean 41.1%; 3.2 cm3) was achieved in all patients.

Conclusions

Gamma Knife surgery is a safe and effective treatment for intracranial GJTs. The tumor volume reductions achieved are comparable to those achieved using microsurgery but with a much lower rate of side effects. More studies with longer follow-up times are necessary to confirm these very promising results.

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.

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.

[Paragangliomas of the head and neck. Part 2: Therapy and follow-up]

Paragangliomas of the head and neck are preferably treated surgically. Planning the surgical approach for temporal bone paragangliomas is performed according to the Fisch classification. Small temporal paragangliomas can be removed in a transtympanic or transmastoidal procedure. Locally advanced paragangliomas of the head and neck have to be embolized presurgically. An occlusion test is also recommended to check the possibility of a resection of the internal carotid artery. Type C and D temporal bone paragangliomas can be removed by different infratemporal approaches. Alternatively, some type C(1,2 )and De,i(1,2) temporal bone paragangliomas can be removed via variations of the juxtacondylar approach. Glomus caroticum tumors are resected transcervically. In cases of contraindications for surgery or in palliative situations radiotherapy is recommended.

Comparison of radiosurgery and conventional surgery for the treatment of glomus jugulare tumors

OBJECT

The optimal management of glomus jugulare tumors remains controversial. Available treatments were once associated with poor outcomes and significant complication rates. Advances in skull base surgery and the delivery of radiation therapy by stereotactic radiosurgery have improved the results obtained using these treatment options. The authors summarize and compare the contemporary outcomes and complications for these therapies.

METHODS

Papers published between 1994 and 2004 that detailed the use of radiosurgery or surgery to treat glomus jugulare tumors were reviewed. Eight radiosurgery series including 142 patients and seven surgical studies including 374 patients were evaluated for neurological outcome, change in tumor size (radiosurgery) or percent of total resection (surgery), recurrences, tumor control, need for further treatment, and complications. The mean age at treatment for patients who underwent surgery and radiosurgery was 47.3 and 56.7 years, respectively. The mean follow-up duration was 49.2 and 39.4 months, respectively. The surgical control rate was 92.1%, with 88.2% of tumors totally resected in the initial surgery. A cerebrospinal fluid leak occurred in 8.3% of patients who underwent surgery and recurrences were found in 3.1%; the mortality rate was 1.3%. Among patients who underwent radiosurgery, tumors diminished in 36.5%, whereas 61.3% had no change in tumor size, and subjective or objective improvements occurred in 39%. Despite the presence of residual tumor in 100% of radiosurgically treated patients, recurrences were found in only 2.1%, the morbidity rate was 8.5%, and there were no deaths.

CONCLUSIONS

Death and recurrences after these treatments are infrequent, and therefore both treatments are considered to be safe and efficacious. Although surgery is associated with higher morbidity rates, it immediately and totally eliminates the tumor. The radiosurgery results are very promising, although the incidence of late recurrence (after 10-20 years) is unknown.

Efficacy and safety of stereotactic radiosurgery for glomus jugulare tumors

Object

Since the mid-1990s the use of radiosurgery for glomus jugulare tumors has grown in popularity. Despite its increased use, follow-up periods for radiosurgery are short and the numbers of patients reported are small. To add to the available information, the authors report their experience with the application of linear accelerator (LINAC) or CyberKnife modalities in 13 patients with 16 tumors.

Methods

All patients were treated with frame-based LINAC or CyberKnife radiosurgery, with doses ranging from 1400 to 2700 cGy. Patients were retrospectively assessed for posttreatment side effects, which included hearing loss, tongue weakness, and vocal hoarseness. The patients' most recent magnetic resonance (MR) images were also assessed for changes in tumor size.

The median follow-up duration was 41 months and the mean follow-up period was 60 months. All tumors remained stable or decreased in size on follow-up MR images. All patients had stable neurological symptoms, and one experienced transient ipsilateral tongue weakness and hearing loss, both of which subsequently resolved. One patient experienced transient ipsilateral vocal cord paresis; however, this individual had received previous external-beam radiation therapy.

Conclusions

The authors' findings continue to support radiosurgery as an effective and safe method of treatment for glomus jugulare tumors that results in low rates of morbidity.

Surgery of Glomus Jugulare Tumors

The treatment of choice for glomus jugulare tumors is still controversial. High rates of morbidity, incomplete resection, and the aggressive behavior of these tumors are the main arguments for advocates of primary radiotherapy. However, constant refinements in skull base techniques have made complete resection of these lesions a realistic goal. The high probability of achieving local control of these tumors by surgery has convinced us to support this option strongly. Between 1993 and 2000 we diagnosed 52 glomus tumors of the temporal bone. Of these patients, only 42 had a class C lesion (glomus jugulare) and were included in this study; 37 of these patients underwent surgery, 10 of whom had intracranial extension of the disease. The overall resection rate was 96 %. Facial nerve function at 1 year was House-Brackmann grade I to II in 52 % of patients and grade III or better in 84 % of patients. Hospitalization was shorter than 14 days in 33 patients (89 %). All patients with pharyngolaryngeal palsy had sufficient compensation at discharge. Twelve vocal chord Teflon injections were performed after surgery to reduce hoarseness and aspiration. No patient died. No relapse was observed (mean follow-up, 4.9 years).

The efficacy of linear accelerator stereotactic radiosurgery in treating glomus jugulare tumors

Treatment of glomus jugulare tumors with radiosurgery has grown in acceptance since the first reported treatment in 1995, but only a few centers have reported their experiences with limited follow up time. We report our experience with stereotactic radiosurgery in nine patients with ten glomus tumors. All patients were treated either with frame based LINAC or Cyberknife with doses ranging from 1600 cGy to 2500 cGy. Three patients received no previous therapy and one patient received additional external beam radiation for concomitant treatment of carotid body tumors. Patients were then followed for post treatment side effects in addition to change in tumor size by MRI evaluation. The median clinical follow-up time was 26 months (mean 54 months), median radiographic follow-up was 21.5 months (mean 46 months), with a range from 3 to 126 months. The results from our center demonstrated nine of ten tumors to be stable in size by MRI exam, and one tumor which regressed in size. Nine patients had stable neurological symptoms, and one patient experienced transient ipsilateral tongue weakness and hearing loss, both of which subsequently resolved. Our results continue to support radiosurgery as a suitable form of treatment for glomus jugulare tumors as evidenced by results from this four and a half year follow-up.

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.