65 YEARS OF THE DOUBLE HELIX: Genetics informs precision practice in the diagnosis and management of pheochromocytoma

Although the authors of the present review have contributed to genetic discoveries in the field of pheochromocytoma research, we can legitimately ask whether these advances have led to improvements in the diagnosis and management of patients with pheochromocytoma. The answer to this question is an emphatic Yes! In the field of molecular genetics, the well-established axiom that familial (genetic) pheochromocytoma represents 10% of all cases has been overturned, with >35% of cases now attributable to germline disease-causing mutations. Furthermore, genetic pheochromocytoma can now be grouped into five different clinical presentation types in the context of the ten known susceptibility genes for pheochromocytoma-associated syndromes. We now have the tools to diagnose patients with genetic pheochromocytoma, identify germline mutation carriers and to offer gene-informed medical management including enhanced surveillance and prevention. Clinically, we now treat an entire family of tumors of the paraganglia, with the exact phenotype varying by specific gene. In terms of detection and classification, simultaneous advances in biochemical detection and imaging localization have taken place, and the histopathology of the paraganglioma tumor family has been revised by immunohistochemical-genetic classification by gene-specific antibody immunohistochemistry. Treatment options have also been substantially enriched by the application of minimally invasive and adrenal-sparing surgery. Finally and most importantly, it is now widely recognized that patients with genetic pheochromocytoma/paraganglioma syndromes should be treated in specialized centers dedicated to the diagnosis, treatment and surveillance of this rare neoplasm.

Clinical Characterization of the Pheochromocytoma and Paraganglioma Susceptibility Genes SDHA, TMEM127, MAX, and SDHAF2 for Gene-Informed Prevention

Importance

Effective cancer prevention is based on accurate molecular diagnosis and results of genetic family screening, genotype-informed risk assessment, and tailored strategies for early diagnosis. The expanding etiology for hereditary pheochromocytomas and paragangliomas has recently included SDHA, TMEM127, MAX, and SDHAF2 as susceptibility genes. Clinical management guidelines for patients with germline mutations in these 4 newly included genes are lacking.

Objective

To study the clinical spectra and age-related penetrance of individuals with mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes.

Design, Setting, and Patients

This study analyzed the prospective, longitudinally followed up European-American-Asian Pheochromocytoma-Paraganglioma Registry for prevalence of SDHA, TMEM127, MAX, and SDHAF2 germline mutation carriers from 1993 to 2016. Genetic predictive testing and clinical investigation by imaging from neck to pelvis was offered to mutation-positive registrants and their relatives to clinically characterize the pheochromocytoma/paraganglioma diseases associated with mutations of the 4 new genes.

Main Outcomes and Measures

Prevalence and spectra of germline mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes were assessed. The clinical features of SDHA, TMEM127, MAX, and SDHAF2 disease were characterized.

Results

Of 972 unrelated registrants without mutations in the classic pheochromocytoma- and paraganglioma-associated genes (632 female [65.0%] and 340 male [35.0%]; age range, 8-80; mean [SD] age, 41.0 [13.3] years), 58 (6.0%) carried germline mutations of interest, including 29 SDHA, 20 TMEM127, 8 MAX, and 1 SDHAF2. Fifty-three of 58 patients (91%) had familial, multiple, extra-adrenal, and/or malignant tumors and/or were younger than 40 years. Newly uncovered are 7 of 63 (11%) malignant pheochromocytomas and paragangliomas in SDHA and TMEM127 disease. SDHA disease occurred as early as 8 years of age. Extra-adrenal tumors occurred in 28 mutation carriers (48%) and in 23 of 29 SDHA mutation carriers (79%), particularly with head and neck paraganglioma. MAX disease occurred almost exclusively in the adrenal glands with frequently bilateral tumors. Penetrance in the largest subset, SDHA carriers, was 39% at 40 years of age and is statistically different in index patients (45%) vs mutation-carrying relatives (13%; P < .001).

Conclusions and Relevance

The SDHA, TMEM127, MAX, and SDHAF2 genes may contribute to hereditary pheochromocytoma and paraganglioma. Genetic testing is recommended in patients at clinically high risk if the classic genes are mutation negative. Gene-specific prevention and/or early detection requires regular, systematic whole-body investigation.

Current approaches and recent developments in the management of head and neck paragangliomas

Head and neck paragangliomas (HNPGLs) are rare neuroendocrine tumors belonging to the family of pheochromocytoma/paraganglioma neoplasms. Despite advances in understanding the pathogenesis of these tumors, the growth potential and clinical outcome of individual cases remains largely unpredictable. Over several decades, surgical resection has long been the treatment of choice for HNPGLs. However, increasing experience in various forms of radiosurgery has been reported to result in curative-like outcomes, even for tumors localized in the most inaccessible anatomical areas. The emergence of such new therapies challenges the traditional paradigm for the management of HNPGLs. This review will assist and guide physicians who encounter patients with such tumors, either from a diagnostic or therapeutic standpoint. This review will also particularly emphasize current and emerging knowledge in genetics, imaging, and therapeutic options as well as the health-related quality of life for patients with HNPGLs.

Genetics of hereditary head and neck paragangliomas

BACKGROUND

The purpose of this study was to give an overview on hereditary syndromes associated with head and neck paragangliomas (HNPGs).

METHODS

Our methods were the review and discussion of the pertinent literature.

RESULTS

About one third of all patients with HNPGs are carriers of germline mutations. Hereditary HNPGs have been described in association with mutations of 10 different genes. Mutations of the genes succinate dehydrogenase subunit D (SDHD), succinate dehydrogenase complex assembly factor 2 gene (SDHAF2), succinate dehydrogenase subunit C (SDHC), and succinate dehydrogenase subunit B (SDHB) are the cause of paraganglioma syndromes (PGLs) 1, 2, 3, and 4. Succinate dehydrogenase subunit A (SDHA), von Hippel-Lindau (VHL), and transmembrane protein 127 (TMEM127) gene mutations also harbor the risk for HNPG development. HNPGs in patients with rearranged during transfection (RET), neurofibromatosis type 1 (NF1), and MYC-associated factor X (MAX) gene mutations have been described very infrequently.

CONCLUSION

All patients with HNPGs should be offered a molecular genetic screening. This screening may usually be restricted to mutations of the genes SDHD, SDHB, and SDHC. Certain clinical parameters can help to set up the order in which those genes should be tested.

EANM 2012 guidelines for radionuclide imaging of phaeochromocytoma and paraganglioma

PURPOSE

Radionuclide imaging of phaeochromocytomas (PCCs) and paragangliomas (PGLs) involves various functional imaging techniques and approaches for accurate diagnosis, staging and tumour characterization. The purpose of the present guidelines is to assist nuclear medicine practitioners in performing, interpreting and reporting the results of the currently available SPECT and PET imaging approaches. These guidelines are intended to present information specifically adapted to European practice.

METHODS

Guidelines from related fields, issued by the European Association of Nuclear Medicine and the Society of Nuclear Medicine, were taken into consideration and are partially integrated within this text. The same was applied to the relevant literature, and the final result was discussed with leading experts involved in the management of patients with PCC/PGL. The information provided should be viewed in the context of local conditions, laws and regulations.

CONCLUSION

Although several radionuclide imaging modalities are considered herein, considerable focus is given to PET imaging which offers high sensitivity targeted molecular imaging approaches.

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.

Germline mutations of the TMEM127 gene in patients with paraganglioma of head and neck and extraadrenal abdominal sites

BACKGROUND

Hereditary pheochromocytoma is associated with germline mutations of a set of susceptibility genes to which the TMEM127 gene has recently been added. Patients with TMEM127 mutations have been thus far exclusively identified with adrenal tumors.

PATIENTS AND METHODS

A population-based series of 48 consecutive individuals from the European-American Pheochromocytoma Paraganglioma Registry with multiple paraganglial tumors and, of these, one extraadrenal paraganglial tumor were selected for this study. They all had normal results when screened for germline mutations of the genes RET, VHL, SDHB, SDHC, and SDHD. Germline mutation analysis of the TMEM127 gene included a search for intragenic mutations and large rearrangements.

RESULTS

Of the 48 eligible patients with extraadrenal paraganglial tumors, two (4.2%) were found to have TMEM127 mutations. One patient had multiple head and neck paraganglioma and one retroperitoneal extraadrenal and adrenal tumor.

CONCLUSION

TMEM127 germline mutations confer risks of extraadrenal paraganglial tumors in addition to the documented adrenal pheochromocytoma. Thus, surveillance for extraadrenal and adrenal paraganglial tumors is likely warranted in TMEM127 mutation carriers, although the true prevalence should be evaluated in patients with extraadrenal paraganglial tumors.

Posttraumatic reactive fibrous bone neoformation of the anterior skull base mimicking osteosarcoma

OBJECTIVES

Malignant bone tumors and fibro-osseous bone lesions of the skull base are uncommon, although fibrous dysplasia in this anatomic location is not a rare condition. In general, fibro-osseous lesions of the skull are often difficult to classify on either clinical presentation, radiological findings, or histological presentation alone. The objective of this article is to present a probably important differential in the management of bony neoformations of the skull and to highlight the diagnostic difficulties when dealing with osseous and fibro-osseous conditions affecting the craniofacial bones.

DESIGN

We present here a novel case of posttraumatic reactive fibrous bone neoformation of the anterior skull base mimicking osteosarcoma in a 16-year-old boy.

RESULTS

Diagnostic steps, clinical, histological, and radiological presentation, as well as surgical treatment are described in detail. The international medical literature concerning reactive fibrous bone neoformations is reviewed, and the problem of adjusting the correct differential diagnosis when dealing with fibro-osseous bone lesions of the skull base is discussed.

CONCLUSIONS

The highlights of this case are an uncommon location of a rare pathological entity, which might constitute an important differential of fibro-osseous conditions affecting the craniofacial bones.

[Chondrosarcoma of the larynx. Experience gained in Freiburg since 1999]

BACKGROUND

Chondrosarcomas are rare tumors of the head and neck. Nevertheless, they display the most common non-epithelial malignancy of the larynx.

MATERIALS AND METHODS

Between 1999 and February 2010 we treated six patients with laryngeal chondrosarcoma. The group included two female and four male patients ranging in age from 54 to 82 years.

RESULTS

An 82-year-old female patient died 3 months after diagnosis and tracheostomy due to other underlying diseases. An 82-year-old male patient underwent primary radiation therapy. In the other patients, we performed a modified hemilaryngektomy in three cases and a laryngectomy in one. In those four cases, there were no signs of recurrent disease 50, 85, 87 and 95 months after surgery, respectively. There were no local or distant metastases.

CONCLUSIONS

Chondrosarcomas of the larynx are slow growing neoplasms. Metastases occur in less than 3% of cases. Complete resection is the therapy of choice. Function-preserving surgical approaches should be favoured.

[Exophytic tumor of the parotid gland]

An 81-year-old male patient presented at our department with a large (diameter 10 cm), exophytic lesion in the right parotid region. Magnetic resonance imaging showed the tumor to derive from the lateral part of the parotid gland. We performed complete tumor resection with selective ipsilateral neck dissection. The facial nerve could be preserved. The postoperative course was uneventful. Histopathologic and immunohistochemical examinations revealed a malignant fibrous histiocytoma. We present the diagnostic and therapeutic options of this unusual malignancy of the parotid gland.

Parasympathetic paragangliomas are part of the Von Hippel-Lindau syndrome

CONTEXT

Von Hippel-Lindau (VHL) disease, caused by germline mutations in the VHL gene, is a hereditary tumor syndrome manifested by hemangioblastomas, clear cell renal cell carcinomas, and pheochromocytomas. In addition, a multitude of other rare tumors, including parasympathetic paragangliomas, can occur and even be the sole manifestation of VHL disease. The VHL gene is a bona fide tumor suppressor gene with biallelic inactivation contributing to tumor formation. However, in parasympathetic paragangliomas occurring in VHL disease, biallelic inactivation of the VHL gene has not been demonstrated to date.

DESIGN

The head and neck paragangliomas of two VHL patients were analyzed for mutations by direct sequencing of the VHL gene. In addition loss of heterozygosity analysis was performed for three microsatellite loci near the VHL gene. To rule out other underlying genetic causes of the parasympathetic paragangliomas, mutation analysis of the SDHB, SDHC, and SDHD genes was also performed.

RESULTS

Apart from germline VHL mutations, no additional mutations were found in the paraganglioma-related tumor suppressor genes SDHB, SDHC, and SDHD. Analysis of paraganglioma tissue revealed loss of the VHL wild-type allele in both tumors, indicating that in these tumors biallelic VHL gene inactivation occurred.

CONCLUSIONS

These findings indicate that parasympathetic paragangliomas in VHL disease, although rare, are part of the syndrome and related to VHL gene inactivation. Clinicians should be aware of the potential occurrence of parasympathetic paragangliomas in VHL disease.

Head and neck paragangliomas in von Hippel-Lindau disease and multiple endocrine neoplasia type 2

BACKGROUND

Head and neck paragangliomas (HNPs) occur as sporadic or familial entities, the latter mostly in association with germline mutations of the SDHB, SDHC, or SDHD (SDHx) genes. Heritable non-SDHx HNP might occur in von Hippel-Lindau disease (VHL, VHL gene), multiple endocrine neoplasia type 2 (MEN2, RET gene), and neurofibromatosis type 1 (NF1, NF1 gene). Reports of non-SDHx HNP presentations are scarce and guidance for genetic testing nonexistent.

PATIENTS AND METHODS

An international consortium registered patients with HNPs and performed mutation analyses of the SDHx, VHL, and RET genes. Those with SDHx germline mutations were excluded for purposes of this study. Personal and family histories were evaluated for paraganglial tumors, for the major tumor manifestations, and for family history of VHL, MEN2, or NF1.

RESULTS

Twelve patients were found to have hereditary non-SDHx HNPs of a total of 809 HNP and 2084 VHL registrants, 11 in the setting of germline VHL mutations and one of a RET mutation. The prevalence of hereditary HNP is five in 1000 VHL patients and nine in 1000 non-SDHx HNP patients. Comprehensive literature review revealed previous reports of HNPs in five VHL, two MEN2, and one NF1 patient. Overall, 11 here presented HNP cases, and four previously reported VHL-HNPs had lesions characteristic for VHL and/or a positive family history for VHL.

CONCLUSIONS

Our observations provide evidence that molecular genetic testing for VHL or RET germline mutations in patients with HNP should be done only if personal and/or family history shows evidence for one of these syndromes.

Malignant peripheral nerve sheath tumour of the paranasal sinuses and the anterior skull base

BACKGROUND

Malignant peripheral nerve sheath tumours (MPNSTs) are highly aggressive neoplasms with a marked propensity for local recurrence and metastatic spread. The management of MPNSTs continues to challenge pathologists and surgeons. As MPNSTs of the paranasal sinuses and the skull base are rare, prognostic factors and treatment modalities have not been consistently identified.

PATIENTS AND METHODS

We present a case of MPNST of the anterior skull base and provide an overview of all MPNSTs reported since 1970, in which the tumour location was the anterior skull base or the paranasal sinuses.

RESULTS

Literature review revealed 33 well-documented cases of MPNSTs in this anatomic location. These cases were analysed with emphasis on age, gender, affected site, therapy, outcome, presence of neurofibromatosis, local recurrence and metastases.

CONCLUSIONS

Despite multimodal therapy and advances in surgical techniques, the prognosis of MPNST located in the paranasal sinuses and the anterior skull base remains dismal. Outcome is mainly a function of local control by surgical resection. Adjuvant radiochemotherapy has shown no benefit. It may therefore be advisable to abstain from radiochemotherapy in order to improve chances for surgical intervention in case of recurrent disease. Close follow-up investigations are indispensable.

Kraniofaziale Fibröse Dysplasie: Observieren oder Operieren?

BACKGROUND

The aetiologic correlations of fibrous dysplasia (FD) are more and more decoded by molecular biology, improved imaging procedures, and the use of computer assisted surgery--thus a review of present diagnostics and therapy methods is evaluated.

METHOD

The valid methods of diagnostic and therapy procedures of craniofacial FD were retrospectively analysed in a collective of 9 patients in consideration of literature. The criteria of the decision for diagnosis and surgical procedures were evaluated.

RESULTS

According to the literature, diagnosis was ascertained with modern CT and MRI scans. Bone scintigraphy was only used additionally in particular questions. In case of unclear radiological findings histomorphological procedures were used complementarily to distinguish FD from other bone tumors. The aim of surgical intervention was to reduce pain, to restore the function in compression symptoms, to recover original ostia, or to restore the natural geometry of the face.

CONCLUSIONS

Current imaging procedures allow differential diagnosis from other benign bone tumors but also from malignancies. The therapy of FD is conservative (wait and scan) or operative in dependence on the localisation, the extension and the clinical manifestations of the disease. In the future molecular biological methods could function as supporting instrument for diagnosis if histomorphological results are not meaningful.

Von-Hippel-Lindau-Erkrankung

Von Hippel-Lindau disease is an important hereditary tumor syndrome with a clear option for effective treatment if diagnosed in time. Interdisciplinary cooperation is the key to successful management. Major components of the disease are retinal capillary hemangioblastomas, hemangioblastomas of cerebellum, brain stem and spine, renal clear cell carcinomas, pheochromocytomas, multiple pancreatic cysts and islet cell carcinomas, tumors of the endolymphatic sac of the inner ear, and cystadenomas of the epididymis and broad ligament. A well structured screening program should be performed at yearly intervals.

Genetic and Clinical Investigation of Pheochromocytoma: A 22-Year Experience, from Freiburg, Germany to International Effort

Although deceptively simple, the etio-pathogenesis of pheochromocytoma represents a clinical and molecular genetic investigative challenge. Here, we summarize, from a historical point of view, the 22-year-long studies initiated at the University of Freiburg, which developed from a local experience to a national and finally an international effort. All research activities are translational and clinical and hence, registry based and intended to improve the outcome of the patients, whether by improved detection, prevention, or treatment. Major clinical steps are the prospective study on hormone tests and imaging techniques for adrenal and extra-adrenal abdominal tumors as well as the concept of organ sparing and endoscopic tumor resection. Further, we introduced 18-fluoro-dopa positron emission tomography. Population-based registries were used in order to identify germline mutations in the susceptibility genes VHL, RET, SDHB, and SDHD in non-syndromic pheochromocytoma. We differentiated distinct clinical features of paraganglioma syndromes associated with SDHB and SDHD gene mutations. Finally, we identified predictors and prevalence of paraganglioma syndromes associated with mutations of the SDHC gene.

The free vastus lateralis flap for reconstruction in ablative oncologic head and neck surgery

AIMS

The vastus lateralis muscle is an accessory extensor for the knee suitable as a free myocutaneous flap in reconstructive head and neck surgery. We report the use of this muscle as a flap.

METHODS

We have used the free myocutaneous vastus lateralis flap for reconstruction following ablative head and neck tumour surgery in six patients. The clinical outcome, time of surgery for flap preparation and anatomosis, follow-up and functional outcome were analysed.

RESULTS

Five of our patients showed a very satisfactory functional and cosmetic outcome. Post-operatively, there was no prolonged immobilisation and no limitation of movement to the hip and knee. No unfavourable side-effects at the donor side were noted.

CONCLUSIONS

We find this flap a very useful addition to our free myocutaneous flap armamentarium. It has a specific suitability for replacing large defects.

Predictors and prevalence of paraganglioma syndrome associated with mutations of the SDHC gene

CONTEXT

Paraganglioma syndrome includes inherited head and neck paragangliomas (HNPs) and adrenal or extra-adrenal pheochromocytomas and are classified according to the susceptibility genes SDHB, SDHC, and SDHD. In contrast with those with germline mutations of the SDHB and SDHD genes, clinical and genetic data on patients with mutations of SDHC are scarce.

OBJECTIVE

To determine the prevalence and clinical characteristics of SDHC mutation carriers compared with patients with SDHB and SDHD mutations and with sporadic cases.

DESIGN, SETTING, AND PATIENTS

Genetic screening for SDHC mutations in an international HNP registry of 121 unrelated index cases and in 371 sporadic cases from a pheochromocytoma registry, conducted January 1, 2001, until December 31, 2004. Identified index cases and affected relatives were clinically evaluated.

MAIN OUTCOME MEASURES

Prevalence of and clinical findings for SDHC mutation-associated HNPs vs those with SDHB and SDHD mutations.

RESULTS

The prevalence of SDHC carriers was 4% in HNP but 0% in pheochromocytoma index cases. None of the SDHC mutation carriers had signs of pheochromocytoma. We compared HNPs in 22 SDHC mutation carriers with the HNPs of SDHB (n = 15) and SDHD (n = 42) mutation carriers and with 90 patients with sporadic HNPs. Location, number of tumors, malignancy, and age were different: more carotid body tumors were found in SDHC (13/22 [59%]) than in sporadic HNPs (29/90 [32%], P = .03), as well as fewer instances of multiple tumors in SDHC (2/22) than in SDHD (24/42; P<.001), 0 malignant tumors in SDHC vs 6/15 in SDHB (P = .002), and younger age at diagnosis in SDHC than in sporadic HNPs (45 vs 52 years; P = .03).

CONCLUSIONS

Patients with HNP, but not those with pheochromocytoma, harbor SDHC mutations in addition to those in SDHB and SDHD. In total, more than one quarter of HNP patients carry a mutation in 1 of these 3 genes. Head and neck paragangliomas associated with SDHC mutations are virtually exclusively benign and seldom multifocal. Analysis for germline mutations of SDHC is recommended in apparently sporadic HNP to identify risk of inheritance.

[Etiology and therapy of the internal jugular vein thrombosis]

BACKGROUND

Thromboses of the upper limp and neck are rare in comparison with those of the lower extremities. Internal jugular vein thrombosis (IJVT) is a serious event with a potentially fatal outcome. Complications include pulmonary embolism, sepsis with septic emboli to different organs and tissues as well as intracranial propagation of the thrombus with cerebral edema. As any thrombosis, IJVT is precipitated by Virchow's triad: endothelial damage, alteration of blood flow and hypercoagulability. The history and examination in patients with an IJVT may be vague and misleading. Patients may present with a painful swelling of the neck but they may also be absolutely asymptomatic. Imaging procedures frequently used to diagnose an IJVT include sonography with color-coded duplex sonography, computed tomography, magnetic resonance imaging as well as magnetic resonance venography. Up to date, there is no standardized treatment regimen for patients with an IJVT.

PATIENTS AND METHODS

This retrospective study includes all ten patients with an IJVT who were seen at our department between January 2000 and January 2004. There were six female and four male patients. The average age was 49.7 years, ranging from 28 to 79 years.

RESULTS

In five cases, the thrombosis was associated with a malignant tumor. In four patients, it was caused by a deep neck space infection and in one case the IJVT was due to cervical, intravenous drug abuse. Two patients were found to be pregnant (one tumor patient and one patient with a deep neck space infection). In all cases, a ten day treatment regimen with intravenous antibiotics and anticoagulant therapy was initiated. Oral or subcutaneous anticoagulation was continued for six weeks to six months. No complications were seen in any patient. In three patients a revascularization of the affected vessel could be demonstrated with color-coded duplex sonography six months after the initial presentation.

CONCLUSIONS

Thrombosis of the IJV is probably underdiagnosed. Since the clinical presentation may be vague or misleading, a high degree of suspicion is required to make the diagnosis. The potential complications such as pulmonary embolism or intracranial propagation of the thrombus may be fatal. Whenever the thrombosis is not caused by an inflammatory process, a malignant tumor should be excluded. We recommend a therapy with intravenous antibiotics as well as a systemic anticoagulation. Ligation or resection of the internal jugular vein is reserved for patients who develop complications despite adequate medical therapy.

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.

[Diagnosis and management of cervical paragangliomas: the Freiburg experience]

BACKGROUND

Paragangliomas of the head and neck represent rare tumors of neural crest origin that arise from chemoreceptors. They are highly vascular neoplasms that are benign in the majority of cases. There are controversial discussions concerning the different treatment options for cervical paragangliomas.

PATIENTS

Between January 1992 and November 2003 a total of 13 patients with 15 cervical paragangliomas were treated at the Department of Otorhinolaryngology - Head and Neck Surgery, University of Freiburg. Our study includes eight female and five male patients with a mean age of 39.9 years (range: 20 - 79 years). There were 14 carotid body tumors and one vagal paraganglioma.

RESULTS

14 tumors were resected and one underwent primary radiation. In four patients we noted a total of 8 permanent, postoperative nerve deficits. During follow-up no recurrent tumors were seen.

CONCLUSION

Complete surgical removal represents the therapy of choice for the majority of cervical paragangliomas. In cases of multiple head and neck paragangliomas or in patients with underlying diseases, primary radiation should be discussed as a treatment option.

[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.

Distinct clinical features of paraganglioma syndromes associated with SDHB and SDHD gene mutations

CONTEXT

Germline mutations of the genes encoding succinate dehydrogenase subunits B (SDHB) and D (SDHD) predispose to paraganglioma syndromes type 4 (PGL-4) and type 1 (PGL-1), respectively. In both syndromes, pheochromocytomas as well as head and neck paragangliomas occur; however, details for individual risks and other clinical characteristics are unknown.

OBJECTIVE

To determine the differences in clinical features in carriers of SDHB mutations and SDHD mutations.

DESIGN, SETTING, AND PATIENTS

Population-based genetic screening for SDHB and SDHD germline mutations in 417 unrelated patients with adrenal or extra-adrenal abdominal or thoracic pheochromocytomas (n = 334) or head and neck paragangliomas (n = 83), but without syndromic features, from 2 registries based in Germany and central Poland, conducted from April 1, 2000, until May 15, 2004.

MAIN OUTCOME MEASURES

Demographic and clinical findings with respect to gene mutation in SDHB vs SDHD compared with nonmutation carriers.

RESULTS

A total of 49 (12%) of 417 registrants carried SDHB or SDHD mutations. In addition, 28 SDHB and 23 SDHD mutation carriers were newly detected among relatives of these carriers. Comparison of 53 SDHB and 47 SDHD total mutation carriers showed similar ages at diagnosis but differences in penetrance and of tumor manifestations. Head and neck paragangliomas (10/32 vs 27/34, respectively, P<.001) and multifocal (9/32 vs 25/34, respectively, P<.001) tumors were more frequent in carriers of SDHD mutations. In contrast, SDHB mutation carriers have an increased frequency of malignant disease (11/32 vs 0/34, P<.001). Renal cell cancer was observed in 2 SDHB mutation carriers and papillary thyroid cancer in 1 SDHB mutation carrier and 1 SDHD mutation carrier.

CONCLUSIONS

In contrast with SDHD mutation carriers (PGL-1) who have more frequent multifocal paragangliomas, SDHB mutation carriers (PGL-4) are more likely to develop malignant disease and possibly extraparaganglial neoplasias, including renal cell and thyroid carcinomas. Appropriate and timely clinical screening is recommended in all patients with PGL-1 and PGL-4.

[Paragangliomas in the head-/neck region. I: Classification and diagnosis]

Paragangliomas of the head and neck occur sporadically or are hereditary. The hereditary phenotype characteristically occurs between the 2nd and 3rd decade of life; the sporadic phenotype beyond the 4th decade. The hereditary phenotype "paraganglioma syndrome type 1" frequently shows multilocular tumor manifestations and rarely cases of maltransformation. Therefore, paragangliomas should be considered a systemic disease. For diagnosis, an interdisciplinary, step by step procedure is mandatory comprising genetic screening, whole body medical check-up including catecholamine metabolism, and optionally an 18F-Dopa-PET and localised imaging procedures.

[Transvestibular closure with an autologous bone graft as surgical repair of a nasoseptal defect due to Le Fort-I osteotomy]

Defects of the nasal septum are a common complication after nasal surgery. Affected patients frequently suffer from bleeding, crusting and impaired nasal air flow. The surgical closure of septal defects remains a distinctive challenge. Though many different techniques have been described, the failure rate of this procedure remains high. In the case presented here, a large basal septum defect occurred after a prosthetic Le Fort-I osteotomy. The attempt to cover the distance between the bony nasal floor and the nasal septum with pedicled mucosal flaps failed due to extensive scar formation of the nasal mucosa. Therefore a nasal floor elevation by insertion of an autologous bone graft from the iliac crest was conducted. The bone graft was connected with the hard palate via two titanium screws. Other than with an autologous cartilage graft, no major resorption of the bone graft is to be expected. This indirect method for the closure of a basal nasal septum defect is new.