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

Outcomes and Therapeutic Strategies for Head-and-neck Paragangliomas Associated With Succinate Dehydrogenase Mutations

CONTEXT

Natural history and optimal therapeutic strategies of patients with head-and-neck paragangliomas (HNPGL) associated with germline mutations in succinate dehydrogenase genes (SDHx) are barely known. This study aims to describe the outcome of these patients depending on selected strategies.

METHODS

We retrospectively analyzed the outcome of 65 SDHx-mutated patients presenting 108 HNPGL mostly located in the carotid (57%) and jugulotympanic (JT) (21.5%) areas. One hundred five HNPGLs (97%) were nonsecreting and nonmetastatic, with multiple tumors observed in 40 patients (62%). HNPGLs were initially managed by surgery for 56 (52%), monitoring for 31 (29%), and radiotherapy for 21 (19%). Unsuccessful tumor control (UTC) was defined as a tumor volume increase or a need to change therapeutic strategy. During a 7-year median follow-up period, 18 UTCs (17%) were observed in 17 patients. Among operated HNPGLs, 13 (23%) had an UTC, compared with 1 (5%) among the irradiated HNPGL and 4 (13%) among monitored HNPGLs. The incidence of UTC was significantly increased in HNPGL treated by incomplete surgical resection compared to HNPGL treated by complete surgery (50% vs 0%, P < .001). UTC was more frequent in the JT than in other locations (39% vs 11%, P < .002).

RESULTS

Posttherapeutic complications were observed in 34 patients (55%), mainly neurological (73%) or vascular (15%), with a higher incidence after surgery than after irradiation (66% vs 14%, P < .001).

CONCLUSIONS

Most SDHx patients with monitored HNPGLs had a stable disease confirming the interest of initial time for observation before deciding to treat or not, particularly in asymptomatic patients.

A Review of the Evolving Role of Radiotherapy in the Treatment of Neuroendocrine Neoplasms

BACKGROUND

Neuroendocrine neoplasms (NENs) are rare tumours that develop from neuroendocrine cells in various parts of the body. The management of this disease poses a significant challenge because of the heterogeneous clinical presentation and varying degrees of aggressiveness. A multidisciplinary approach is often required in complex clinical situations. Radiotherapy (RT) plays a key role in managing NETs in both curative and palliative settings.

SUMMARY

In this review, we summarize and discuss recent developments in the field of advanced RT in early-stage, locally advanced, and metastatic NENs. We highlight limitations in current approaches and discuss future potential treatment strategies for patients with NENs.

Paragangliomas and Anemia: Literature Review and Case Report

Paragangliomas are rare neuroendocrine tumors that arise from the extra-adrenal autonomic paraganglia, i.e., small organs consisting mainly of neuroendocrine cells that are derived from the embryonic neural crest and have the ability to secrete catecholamines. Paragangliomas can derive from either parasympathetic or sympathetic paraganglia. Most of the parasympathetic ganglia-derived paragangliomas are nonfunctional, and symptoms result from mass effect. Conversely, the sympathetic paragangliomas are functional and produce catecholamine. Although such patients could have symptoms similar to pheochromocytoma, mass effect symptoms, or non-specific symptoms, being benign tumors, they can also present with anemia, specifically iron-deficiency anemia. Considering that neoplastic pathology is chronically accompanied by moderate, normochromic, normocytic anemia, association between paragangliomas that are mostly benign but with a potential degree of malignancy and anemia is not as frequent as expected, with only 12 cases reported in the literature. We report a case of a 54-year-old female patient diagnosed with a paraganglioma of the carotid glomus accompanied by severe normochromic, normocytic anemia, which reached normal limits after excision of the paraganglioma.

Paragangliomas of the head and neck

Paragangliomas are rare neuroendocrine tumors that can be found from the skull base to the pelvis. Head and neck paragangliomas have been historically treated with surgery. However, surgical resection adds risk of injury to vascular structures and cranial nerves that can lead to morbidity such as hoarseness, dysarthria, dysphagia, or aspiration. Recently, improved understanding of the behavior of these tumors and increasing experience in non-surgical treatments such as observation and radiation therapy, have changed the paradigms of management of this entity. Multiple series now show a trend towards a more conservative management, with a higher percentage of patients being observed or treated with radiotherapy. Several factors should be taken into consideration when deciding the most appropriate treatment for head and neck paragangliomas, starting by differentiating carotid body tumors from non- carotid body tumors. In general, surgical resection is normally recommended for carotid body tumors as the complications from treatment are usually minimal. In contrast, for non- carotid body tumors, surgery is often associated with significant functional impairment due to cranial nerve paralysis. As such, non-surgical treatment is now usually recommended for this subset of head and neck paragangliomas. In young patients with no comorbidities and a small to medium carotid body tumors, surgery should be considered. Moreover, surgery should be offered for secreting tumors, malignant tumors, tumors with rapid growth or increase in symptomatology, and when radiotherapy cannot be performed. Conversely, conservative management with active surveillance or radiotherapy can be offered in the remaining cases in order to avoid unnecessary morbidity while still providing acceptable tumor control.

Clinically Advanced Pheochromocytomas and Paragangliomas: A Comprehensive Genomic Profiling Study

Simple Summary

Clinically advanced pheochromocytomas and paragangliomas are a rare form of endocrine malignancy which can occur in familial and sporadic clinical settings and feature a variety of genomic alterations. Comprehensive genomic profiling (CGP) was performed to characterize the genomic alterations (GA) in clinically advanced disease to enable the search for potential therapy targets. Although the GA/tumor is relatively low for clinically advanced disease, CGP can reveal important potential targets for therapy in the metastatic setting including RET, NF1 and FGFR1. Based on this data, further study of CGP as a method of developing precision therapies for clinically advanced disease appears warranted.

Abstract

Patients with clinically advanced paragangliomas (CA-Para) and pheochromocytomas (CA-Pheo) have limited surgical or systemic treatments. We used comprehensive genomic profiling (CGP) to compare genomic alterations (GA) in CA-Para and CA-Pheo to identify potential therapeutic targets. Eighty-three CA-Para and 45 CA-Pheo underwent hybrid-capture-based CGP using a targeted panel of 324 genes. Tumor mutational burden (TMB) and microsatellite instability (MSI) were determined. The GA/tumor frequencies were low for both tumor types (1.9 GA/tumor for CA-Para, 2.3 GA/tumor for CA-Pheo). The most frequent potentially targetable GA in CA-Para were in FGFR1 (7%, primarily amplifications), NF1, PTEN, NF2, and CDK4 (all 2%) and for CA-Pheo in RET (9%, primarily fusions), NF1 (11%) and FGFR1 (7%). Germline mutations in known cancer predisposition genes were predicted in 13 (30%) of CA-Pheo and 38 (45%) of CA-Para cases, predominantly involving SDHA/B genes. Both CA-Para and CA-Para had low median TMB, low PD-L1 expression levels and none had MSI high status. While similar GA frequency is seen in both CA-Para and CA-Para, germline GA were seen more frequently in CA-Para. Low PD-L1 expression levels and no MSI high status argue against strong potential for novel immune checkpoint inhibitors. However, several important potential therapeutic targets in both CA-Para and CA-Para are identified using CGP.

Successful patient outcome following surgery of carotid body tumor and temporary hypoglossal nerve dysfunction

Carotid body tumors, also known as paragangliomas or chemodectomas, are rare tumors. They are mostly benign slow-growing tumors arising from neural crest cells, but can give rise to complications because of their location and close relation to carotid vessels and cranial nerves. A 40-year male patient diagnosed with a carotid body tumor is discussed along with a review of cranial nerve complications associated with the management of carotid body tumors. This case highlights the complete recovery after a temporary hypoglossal nerve deficit following surgery. Another important aspect is that syncopal attacks might occur in carotid body tumors and early surgery is required to prevent complications.

Head and neck paragangliomas: 30-year experience

BACKGROUND

We aimed to review our experience and the changing trends in the management of head and neck paragangliomas (HNPG) over the last three decades.

METHODS

We retrospectively reviewed 103 patients with HNPG treated at our center (1986-2017). We included patients treated with surgery, radiotherapy, and patients maintained under active surveillance.

RESULTS

Of the surgically treated patients (n = 79), 20% (12/59) of the carotid body tumors (CBT) had a cranial nerve deficit as sequela compared to 95% (19/20) of the non-CBT. Radiotherapy controlled growth in all tumors treated with this modality (n = 10). Of the initially observed patients, 70% (14/20) remained stable and did not require additional treatment. Stratifying by decades, there was a progressive increase in patients initially attempted to be observed and a decrease in upfront surgery. No deaths attributable to the HNPG were encountered.

CONCLUSIONS

Surgery is an effective treatment for CBT. Nonsurgical treatment should be considered for non-CBT.

Paragangliomas of the Head and Neck: Local Control and Functional Outcome Following Fractionated Stereotactic Radiotherapy

OBJECTIVES

To investigate local control and functional outcome following state-of-the-art fractionated stereotactic radiotherapy (FSRT) for paragangliomas of the head and neck.

METHODS

In total, 40 consecutive patients with paragangliomas of the head and neck received conventionally FSRT from 2003 to 2016 at the Department of Radiation Oncology of the University Hospital Erlangen. Local control, toxicities, and functional outcome were examined during follow-up. In total, 148 magnetic resonance imaging studies were subjected to longitudinal volumetric analysis using whole tumor segmentation in a subset of 22 patients.

RESULTS

A total of 80.0% (32/40) of patients received radiotherapy as part of their primary treatment. In 20.0% (8/40) of patients, radiation was used as salvage treatment after tumor recurrence in patients initially treated with surgery alone. The median dose applied was 54.0 Gy (interdecile range, 50.4 to 56.0 Gy) in single doses of 1.8 or 2 Gy. Local control was 100% after a median imaging follow-up of 52.2 months (range, 0.8 to 152.9 mo). The volumetric analysis confirmed sustained tumor control in a subset of 22 patients and showed transient enlargement (range, 129.6% to 151.2%) in 13.6% of cases (3/22). After a median volumetric follow-up of 24.6 months mean tumor volume had diminished to 86.1% compared with initial volume. In total, 52.5% (21/40) of patients reported improved symptoms after radiotherapy, 40% (16/40) observed no subjective change with only 7.5% (3/40) reporting significant worsening.

CONCLUSIONS

State-of-the-art FSRT provides excellent control and favorable functional outcome in patients with paragangliomas of the head and neck. The volumetric analysis provides improved evidence for sustained tumor control.

Bilateral malignant paragangliomas in a patient: a rare case report

BACKGROUND

Paragangliomas are neuroendocrine neoplasms that arise from the extra-adrenal paraganglia of the autonomic nervous system. Approximately 3% of all paragangliomas occur in the head and neck region. Most reported cases are benign and unilateral. We present here a rare case of bilateral malignant paragangliomas.

CASE DESCRIPTION

A 28-year-old woman presented to our department with a 10-year history of bilateral neck swelling. Physical examination showed bilateral neck masses with obvious pulsation. Enhanced CT revealed two irregular solid nodules, located in the left and right carotid artery bifurcation, respectively. Carotid artery angiography showed compression of the internal and external carotid arteries by the tumors on both sides. Upon diagnosis of the bilateral carotid body tumors, preoperative embolization was performed. The left-side lesion as well as the lymph nodes were resected and a diagnosis of malignant paraganglioma with lymph node metastasis was made. Genetic studies have shown that familial paragangliomas are associated with germline mutation of succinate dehydrogenase subunits SDHD on 11q23. She was treated with 50-Gy radiotherapy, and a subsequent CT scan performed two years later showed that the right-side lesion was unchanged. She was symptom-free as of the last follow-up.

CONCLUSIONS

The rarity of bilateral malignant paragangliomas makes their management clinically challenging. The primary management of a recognized malignancy should be directed toward complete surgical removal of the primary tumor and regional lymph nodes. Postoperative radiation is beneficial in slowing the progression of residual disease.

Protontherapy of head and neck paragangliomas: A monocentric study

PURPOSE

The aim of this study was to assess efficacy and safety of proton beam therapy of paragangliomas of the head and neck, rare benign tumours developed close to crucial structures such as cranial nerves and vascular tissues.

PATIENTS AND METHODS

Ten patients with a paraganglioma of the head and neck were treated from 2001 to 2014 with image-guided proton therapy. Neurological and ear nose throat symptoms were collected in addition to audiometric testing, before and after the treatment. Acute and late toxicities were assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.

RESULTS

Median age at diagnosis was 52.6years (range: 18.2-65.8years). Proton therapy was the exclusive treatment in six patients and four patients had a postoperative radiotherapy. Median dose was 50.4Gy relative biological effectiveness (RBE; range: 45.0-67.0Gy). With a median follow-up of 24.6months (range: 6.7-46.2 months), local tumour control rate was 100% (stable, n=10). No upper grade 2 acute toxicity was reported. To the latest news, seven patients had controlled symptoms (improved, n=1, stabilized, n=6). One patient out of seven with initial tinnitus had a decrease in his symptoms, while the six other patients had a sustained stabilization.

CONCLUSION

Proton beam therapy is an effective and well-tolerated treatment modality of skull base paragangliomas, with documented functional benefit. A longer follow-up is planned in order to assess local control and long-term toxicities.

The Management of Locally Invasive Primary Thyroid Paraganglioma: A Case Report and Review of the Literature

Paragangliomas (PG) are very rare neuroendocrine tumours, arising from neural crest derived paraganglia of the autonomic nervous system. Primary thyroid paraganglioma (PTPG) is a rare site of PG and only 45 cases have been previously reported. The preoperative diagnosis of PTPGs presents a challenge as the clinical, cytological and histological features overlap with more common primary thyroid cancers. A 55 year old male was found to have significant enlargement of the left lobe of his thyroid. Following lobectomy, the thyroid lobe showed unencapsulated tumour which was positive for synaptophysin, CD56 and S100 (sustentacular cells). Post-operative imaging demonstrated incomplete resection. There was no post-operative radiotherapy and monitoring was by 6-12 monthly MRI. 48 months after his surgery he is alive and well with no evidence of disease progression. The diagnosis of PTPG was only made postoperatively, and although rare should be considered in the differential diagnosis of a hypervascular thyroid nodule.

Malignant Vagal Paraganglioma

Paragangliomas are rare, typically benign neuroendocrine tumors that represent a small portion of head and neck tumors. A small percentage of these are known to have malignant potential. They arise from the carotid body, jugular bulb or vagus nerves. There is limited literature discussing the management of malignant vagal paragangliomas. We present a case of a 25 year old female with a left malignant vagal paraganglioma. The following case presentation will describe the presentation, classic radiologic findings, and management of a malignant vagal paraganglioma along with a review of the literature.

A two-decade experience of head and neck paragangliomas in a whole population-based single centre cohort

Paragangliomas are rare neuroendocrine tumours arising from neural crest-derived tissue. In the head and neck region typical locations are the carotid bifurcation, vagal nerve or jugulotympanic region. Paragangliomas are normally benign, and malignant transformation is rare. During the past decade the understanding of the genetic and molecular aetiology has had an important clinical impact on the management of PGs. This is a retrospective review of all histologically verified paragangliomas diagnosed and managed at an academic tertiary care referral centre between 1990 and 2010. Data on age, sex, symptoms, tumour location, management and follow-up were recorded. There were 64 patients with 74 tumours. Thirty-six per cent of the tumours were located in the carotid body region, 48 % in the jugulotympanic region and 15 % in the vagal nerve. One tumour was located in the dorsal neck. Most (95 %) of the patients were treated primarily with surgery and with curative intent. Definitive radiation therapy was primarily given to two patients. Recurrent or residual tumours were treated with surgery in three patients and with radiation therapy in nine patients. The typical long-term post-operative sequel was vocal cord paralysis. Local recurrence was found in 6 % of patients. Symptoms and findings related to paragangliomas are variable and management should be individualized. Surgery remains the primary choice of the current treatment options, but often is challenging and warrants a multidisciplinary approach. We present an algorithm on the management of head and neck paragangliomas based on current knowledge.

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

Paragangliomas are rare, slow-growing tumors that frequently arise in the head and neck, with the carotid bodies and temporal bone of the skull base being the most common sites. These neoplasms are histologically similar to pheochromocytomas that form in the adrenal medulla and are divided into sympathetic and parasympathetic subtypes based on functionality. Skull base and head and neck region paragangliomas (SHN-PGs) are almost always derived from parasympathetic tissue and rarely secrete catecholamines. However, they can cause significant morbidity by mass effect on various cranial nerves and major blood vessels. While surgery for SHN-PG can be curative, postoperative deficits and recurrences make these lesions challenging to manage. Multiple familial syndromes predisposing individuals to development of paragangliomas have been identified, all involving mutations in the succinate dehydrogenase complex of mitochondria. Mutations in this enzyme lead to a state of “pseudohypoxia” that upregulates various angiogenic, survival, and proliferation factors. Moreover, familial paraganglioma syndromes are among the rare inherited diseases in which genomic imprinting occurs. Recent advances in gene arrays and transcriptome/exome sequencing have identified an alternate mutation in sporadic SHN-PG, which regulates proto-oncogenic pathways independent of pseudohypoxia-induced factors. Collectively these findings demonstrate that paragangliomas of the skull base and head and neck region have a distinct genetic signature from sympathetic-based paragangliomas occurring below the neck, such as pheochromocytomas. Paragangliomas serve as a unique model of primarily surgically treated neoplasms whose future will be altered by the elucidation of their genomic complexities. In this review, the authors present an analysis of the molecular genetics of SHN-PG and provide future directions in patient care and the development of novel therapies.

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.

Malignant head and neck paragangliomas: treatment efficacy and prognostic indicators

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Treatment of cervical paragangliomas

OBJECTIVE

Review of the treatment of cervical paraganglioma.

MATERIAL AND METHODS

Review of the literature based on a Medline database.

RESULTS

The treatment of choice consists of a multidisciplinary approach based on a detailed clinical, laboratory and radiological work-up. Vascular reconstruction may be necessary when the tumour invades the artery wall. The main complication of surgery is damage to cranial nerves involved in speech and/or swallowing. Treatment of bilateral tumours must be conducted in two stages. The first side to be operated depends on the sites and size of the tumours, as the primary objective is to avoid bilateral vagus nerve palsy. Radiotherapy has been used to treat paragangliomas for several years and achieves tumour stabilization in the majority of cases. Potential indications reported in the literature are: inoperable tumours, recurrence after surgery, some bilateral tumours and malignant tumours.

CONCLUSION

Surgery is the standard treatment for cervical paraganglioma. Radiotherapy can be proposed when surgery is contraindicated.

Management of Head and Neck Paragangliomas: A Series of 9 Cases and Review of the Literature

We conducted a retrospective study of the long-term functional results of surgery for head and neck paragangliomas. Our study population was made up of 9 patients—4 men and 5 women, aged 22 to 59 years (mean: 46.6; median: 51)—who had undergone surgical excision of a head and neck paraganglioma from January 2002 through December 2006 in the ENT Department at Pugliese-Ciaccio Hospital in Catanzaro, Italy. Of the 9 paragangliomas, 4 were carotid body tumors, 2 were glomus tympanicum tumors, and 3 were glomus vagale tumors. None of the cases was bilateral or hereditary. Complete tumor resection was achieved in 8 patients; in the remaining patient, a small amount of intradural residual vagus nerve paraganglioma had to be left in situ. The internal carotid artery was preserved in all 4 resections of carotid body tumors. There was only 1 case of postoperative lower cranial nerve deficits, which occurred in a patient with a carotid body tumor. Follow-up ranged from 12 to 53 months (mean: 37.2; median: 36), and no recurrences were documented. Our small sample showed that surgical treatment of head and neck paragangliomas provided excellent tumor control with low postoperative morbidity, even in patients with large tumors. A wait-and-scan policy may be more appropriate for patients at an advanced age or who are otherwise at high surgical risk, as well as for those whose tumors have recurred following radiotherapy.

[Endocrine surgery for neck paraganglioma: operation, radiation therapy or wait and scan?]

BACKGROUND

Head and neck paraganglioma (HNP) represent rare endocrine tumors. Therapy is decided on genetic findings, tumor characteristics (e.g. tumor size, localization and dignity), age of patient and symptoms. In terms of local control radiation therapy is as equally effective as surgery but surgical morbidity rates secondary to cranial nerve injuries remain high.

PATIENTS

Based on 6 patients with 11 solitary (4 patients) and multiple (2 patients) HNP (8 carotid body tumors, 1 vagal, 1 jugular and 1 jugulotympanic paraganglioma) the specific characteristics of the need for surgery as well as correct choice of treatment in cases of sporadic succinate dehydrogenase (SDH) negative and hereditary SDH positive HNP will be exemplarily demonstrated.

RESULTS

A total of 6 carotid body tumors (four sporadic, two hereditary) were resected in 4 patients, five as primary surgery and one as a revision procedure. In one case a preoperative embolization was performed 24 h before surgery. Malignancy could not be proven in any patient. The 30-day mortality was zero. In the patient with bilateral hereditary carotid body tumors, unilateral local recurrent disease occurred. After resection of the recurrent tumor permanent unilateral paralysis of the laryngeal nerve, glossopharyngeal nerve and hypoglossal nerve occurred. All patients were followed-up postoperatively for a mean of 64 months (range 23-78 months) with a local tumor control rate of 100%. The overall survival rate after 5 years was 100%.

CONCLUSIONS

Given a very strict indication with awareness of surgical risks selective surgery has a key position with low postoperative morbidity in the treatment of HNPs. We prefer surgery for small unilateral paraganglioma, malignant or functioning tumors.

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.

Head and neck paragangliomas

BACKGROUND

The purpose of this study was to describe the natural history and optimal treatment for head and neck paragangliomas (PGs).

METHODS

Our methods were the review of the pertinent literature.

RESULTS

PGs are rare tumors seen most commonly in the head and neck. Approximately 90% are sporadic; the remainder are familial and related to mutations of the succinate dehydrogenase (SDH) gene complex. Most PGs are benign and slow growing; 6% to 19% are malignant, as evidenced by the development of metastases. PGs may be treated by complete resection or moderate-dose radiotherapy with a ≥90% likelihood of cure. The optimal radiotherapy dose is approximately 45 Gy/25 fractions/5 weeks. The treatment modality selected depends on the risk of complications. Due to their rarity, the optimal treatment for malignant PGs is unclear.

CONCLUSION

PGs may be treated by either complete resection or radiotherapy with a high likelihood of success. Treatment depends on the location and extent of the PG and the morbidity associated with treatment.

Synchronous malignant vagal paraganglioma with contralateral carotid body paraganglioma treated by radiation therapy

Paragangliomas are rare tumors and very few cases of malignant vagal paraganglioma with synchronous carotid body paraganglioma have been reported. We report a case of a 20-year old male who presented with slow growing bilateral neck masses of eight years duration. He had symptoms of dysphagia to solids, occasional mouth breathing and hoarseness of voice. Fine needle aspiration cytology (FNAC) performed where he lived showed a sinus histiocytosis and he was administered anti-tubercular treatment for six months without any improvement in his symptoms. His physical examination revealed pulsatile, soft to firm, non-tender swellings over the anterolateral neck confined to the upper-mid jugulo-diagastric region on both sides. Direct laryngoscopy examination revealed a bulge on the posterior pharyngeal wall and another over the right lateral pharyngeal wall. Magnetic resonance imaging (MRI), 99mTc-labeled octreotide scan and angiography diagnosed the swellings as carotid body paraganglioma, stage III on the right side with left-sided vagal malignant paraganglioma. Surgery was ruled out as a high morbidity with additional risk to life was expected due to the highly vascular nature of the tumor. The patient was treated with radiation therapy by image guided radiation to a dose of 5040cGy in 28 fractions. At a follow-up at 16 months, the tumors have regressed bilaterally and the patient can take solids with ease.