Hereditary paraganglioma due to the SDHD M1I mutation in a second Chinese family: a founder effect?

OBJECTIVES/HYPOTHESIS

Hereditary paraganglioma is a rare condition that is inherited in an autosomal-dominant fashion. Four distinct loci have been associated with hereditary paraganglioma, including the SDHD, SDHC, and SDHB genes and a locus at 11q13. The SDHD, SDHC, and SDHB genes code for subunits of succinate dehydrogenase, which forms part of the mitochondrial respiratory chain. SDHD mutations are widely distributed along the gene with no apparent hot spots, although a founder effect has been described in the Dutch population.

METHODS

Following a prior report of the SDHD M1I mutation in an Australian Chinese family, a second Chinese family with the same mutation is reported. The proband developed bilateral head and neck paragangliomas at age 34 years and a functioning adrenal pheochromocytoma and two extra-adrenal abdominal paragangliomas 7 years later. His brother had unilateral head and neck paraganglioma at age 39 years. Given the multicentricity of the proband's tumor and the familial clustering of paragangliomas, a clinical diagnosis of hereditary paraganglioma was made, and the proband was tested for a mutation in the SDHD gene.

RESULTS

The proband was found to be heterozygous for the SDHD MII mutation that removes the start codon, and his brother subsequently tested positive for the same mutation. The family is not related to the Australian Chinese family.

CONCLUSION

The finding suggests the possibility of a founder effect in the Chinese population and warrants further investigation.

[Diagnosis and treatment of glomus jugulare tumor]

OBJECTIVE

To investigate the clinical features, diagnosis, and treatment of glomus jugulare tumor.

METHODS

The data of 37 patients of glomus jugulare tumor diagnosed by digital subtraction angiography (DSA) and/or operation and pathology, 14 males (37.8%) and 23 females (62.2%), with an average age of 37.2 (3.5 approximately 66 years) and an average course of 4.3 years (1 month - 19 years), were analyzed.

RESULTS

The tumor was located in the left ear in 19 cases, in the right ear in 17 cases, and in both ears in 1 case, totally 38 ears. The tumor was chromaffin in one case with hypertension. One case was complicated by ipsilateral carotid body tumor, and 2 cases were complicated by ipsilateral cholesteatoma. Thirty cases (81.1%) presented pulsatile tinnitus and hearing loss as the main symptoms. Thirteen cases (35.1%) were diagnosed as glomus jugulare tumor at the first visit, and 24 cases (64.9%) were diagnosed as other diseases with an average misdiagnosis period of 4.4 years. Eighteen tumors originated from typanum and 28 tumors from glomus jugulare. According the Fisch classification 1981, the tumors in 11 ears were type A, in 7 ears were type B, in 7 ears type C, in 5 ears type D1, and in 8 ears type D2. All cases, except the one with bilateral lesions, underwent operation. The tumor was completely resected in 30 cases. Postoperatively, facial paralysis was seen in 6 cases, dizziness, hoarseness, and subauricular necrosis was seen in one case respectively. Of the 25 patients followed up with a mean follow-up time of 5.2 years (1.1 - 16.1 years), 3 died of lung cancer, neuroblastoma, or extensive involvement of glomus jugulare tumor respectively, 19 survived without tumor, and 3 survived with the tumor.

CONCLUSION

Glomus jugulare tumor is likely to involve surrounding important tissues, and to be misdiagnosed. Early surgical removal of the lesion is important.

Jugulotympanic paragangliomas

Jugulotympanic paragangliomas are the most common tumors of the middle ear and temporal bone. Although these larger tumors can prove to be formidable, the advent of microscopic and skull base surgical techniques has greatly enhanced the ability to treat and manage these tumors.

Glomus tympanicum and glomus jugulare tumors

The ideal management of most paragangliomas is complete surgical excision. Because of technical advances, issues of resectability have given way to issues of functional outcome and postsurgical quality of life. This article reviews the surgical strategy for craniocervical paragangliomas. Intracranial extension, defect reconstruction, and cranial nerve rehabilitation are addressed.

[Jugular-tympanic paraganglioma: our experience in 2 years]

The paper is a review of the jugulotympanic paragangliomata seen in our Hospital in a 2 years term. The AA. discuss every case and achieve a checking of several therapeutics procedures accepted for these growths.

[Diagnosis and treatment of brain tumors in jugular foramen region]

OBJECTIVE

To analyze the diagnosis and treatment of brain tumors in jugular foramen region.

METHODS

22 patients with brain tumor in jugular foramen region who had been diagnosed and treated from 1996 to 2000. Considerable literature was reviewed.

RESULTS

Tumor imaging technique showed masses of different shapes in unilateral jugular foramen region. All of the 22 patients underwent operation via different approaches. Total removal of the tumor was achieved in 20 patients and subtotal removal in 2. Pathological examination confirmed the diagnosis of neurinoma in 13 patients, tumor of glomus jugulare in 4, meningioma in 3, chordoma in 1, and metastatic tumor in 1. Only one patient died after operation. The mortality rate was as low as 4.5%.

CONCLUSION

The most common tumors in jugular foramen region are neurinoma, tumor of glomus jugulare, and meningioma. Surgery is effective in treatment of brain tumor in jugular foramen region.

Rupture of an internal carotid artery aneurysm in the petrous temporal bone

A case of otorrhagia following the rupture of an aneurysm of the intrapetrous portion of the internal carotid artery is presented. The aneurysm was successfully treated by balloon occlusion of the parent artery. The problems associated with diagnosis and clinical management of these lesions is discussed and possible solutions suggested.

Glomus faciale, glomus jugulare, glomus tympanicum, glomus vagale, carotid body tumors, and simulating lesions. Role of MR imaging

In summary, MR imaging characteristics of a case of paraganglioma of the facial nerve are reported. The relationship of paragangliomas and the chromaffin system have been discussed. There are many reports of cases of synchronous paragangliomas and pheochromocytomas. These reports, along with simultaneous involvement in familial MEN syndromes, and the common embrylogic origin (neural crest) and similar histopathologic relationships between paragangliomas and pheochromocytoma, all support the fact that they are part of the chromaffin system.

[Main symptom: "pulse-synchronous tinnitus"]

BACKGROUND

In comparison to cochlear or nerval generated ear noises, pulsatile tinnitus is a rare condition. Due to its own etiology, specific diagnostic steps are necessary.

PATIENTS

We present 6 patients with pulsating tinnitus as the leading symptom. By means of these cases the various etiologies, rational diagnosis and therapy will be discussed.

RESULTS

Pulsatile tinnitus is frequently caused by an increased blood flow in the cranial vessels through various pathologies. Besides those diseases going along with a general increase of blood circulation, regional alterations can be classified as hypervascular/hyperemic, arterial or venous conditioned.

CONCLUSIONS

Physical examination and modern imaging can detect the underlying reasons in a quick and reliable way.

[Diagnosis of glomus jugulare tumor recurrence with dynamic contrast medium flow in MRI]

PURPOSE

To evaluate the ability of dynamic MRI to differentiate residual tumor from scar after glomus jugulare (GJ) surgery.

METHODS

26 patients after GJ surgery were examined with dynamic contrast medium MRI on a 1.5 T Philips-Gyro-Scan NT. A T1-weighted TFE sequence was performed to localise the 5 slices for the dynamic study. Subsequently, a T1-weighted TFE sequence was used for the dynamic contrast medium study. We started contrast medium administration and TFE sequence at the same time. The time until acquisition of the first image was 7.4 s, and the interval between two images 7 s (total time 2.24 min). Intensity versus time studies were performed in the region of interest.

RESULTS

2 typical intensity versus time graphs were observed: residual tumors showed a rapid increase in signal intensity, followed by a "wash-out" phase, and a plateau phase in the later course. Scar showed a moderate increase in signal intensity, followed by a plateau phase on a low intensity level. In 9 patients, in whom tumor removal was subtotal, we saw the typical graph of a GJ tumor. 4 of 17 patients with complete tumor removal showed a typical graph like that of residual tumor, 13 of 17 patients showed the typical graph of a scar.

CONCLUSION

With dynamic contrast medium MRI studies, differentiation between residual tumor and scar is possible in patients with prior GJ surgery.

Imaging of tinnitus: a review

Tinnitus, a buzzing or ringing in the ear, may be pulsatile or continuous (nonpulsatile). The distinction, with a detailed clinical evaluation, determines the most appropriate imaging study. Pulsatile tinnitus suggests a vascular neoplasm, vascular anomaly, or vascular malformation. Most of the neoplasms are glomus tympanicum and glomus jugulare tumors. Vascular anomalies may cause pulsatile tinnitus, but the mechanism is unknown, and another (treatable) cause should be sought. Most neoplasms and anomalies are best seen on bone algorithm computed tomographic (CT) studies. Dural vascular malformations are often elusive on all cross-sectional imaging studies; conventional angiography may be necessary to make this diagnosis. Flow-sensitive magnetic resonance (MR) images show vascular loops compressing the eighth cranial nerve. Carotid dissections, aneurysms, atherosclerosis, and fibromuscular dysplasia can be identified on both MR imaging or MR angiographic studies and CT or CT angiographic studies. Otosclerosis and Paget disease are CT diagnoses. Benign intracranial hypertension often has no abnormal imaging findings. For patients with nonpulsatile tinnitus, MR imaging is the study of choice to exclude a vestibular schwannoma or other neoplasm of the cerebellopontine angle cistern. Multiple sclerosis and a Chiari I malformation are rare causes of pulsatile tinnitus, also best seen on MR studies. Many patients with tinnitus have no abnormal imaging findings.

Genetic analysis in the diagnosis of familial paragangliomas

OBJECTIVES

In the management of two related patients with multicentric glomus jugulare tumors, given the incidence of 1:30,000 with approximately 20% familial cases, our objective was to review the genetic characteristics and inheritance patterns of these tumors and to determine what molecular genetic screening possibilities exist for the phenotypically normal family members. In addition, our aim was to review the incidence of various multicentric paraganglioma (PGL) tumor location combinations.

METHODS

Molecular genetic linkage analysis testing was performed on the 2 patients and 14 other unaffected family members. We report the results of this screening and review the literature on the incidence and genetics of paragangliomas.

RESULTS

The inheritance pattern in the literature demonstrates autosomal dominant transmission with maternal imprinting (inactivation). The proclivity for multicentric origin increases to 26% in familial cases, as reflected in our patients. In addition to the two patients, four unaffected family members demonstrated the presence of the disease haplotype at chromosome band 11q23, which indicates a very high likelihood of developing a paraganglioma, given the highly penetrant nature of the disease.

CONCLUSIONS

It is clear that the familial PGL gene locus is situated at chromosome 11q23. The gene itself and its exact degree of penetrance, however, still await identification. Since early detection of paragangliomas reduces the incidence of morbidity and mortality, genotypic analysis as a screening tool in families of affected patients should play a front-line diagnostic role, leading to more timely and cost-effective patient management.

Imaging findings in schwannomas of the jugular foramen

BACKGROUND AND PURPOSE

Tumors of the cranial nerve sheath constitute 5% to 10% of all intracranial neoplasms, yet few articles have described their CT and MR characteristics. We report the imaging findings in a relatively large series of schwannomas of the jugular foramen, contrasting them with other disease entities, especially vestibular schwannomas and tumors of the glomus jugulare.

METHODS

CT and/or MR studies of eight patients who underwent surgery for histologically proved schwannomas were reviewed retrospectively. One additional patient with an assumed schwannoma of the jugular foramen, who did not have surgery, was also included.

RESULTS

Surgical findings showed schwannomas of the glossopharyngeal nerve in seven patients and tumor involvement of both the glossopharyngeal and vagal nerves in one patient. All tumors were partially located within the jugular foramen. Growth extending within the temporal bone was typical. Tumor extended into the posterior cranial fossa in all nine patients and produced mass effect on the brain stem and/or cerebellum in seven patients; in five patients, tumor extended below the skull base. On unenhanced CT scans, tumors were isodense with brain in six patients and hypodense in two. In seven patients, CT scans with bone algorithm showed an enlarged jugular foramen with sharply rounded bone borders and a sclerotic rim. On MR images, T1 signal from tumor was low and T2 signal was high relative to white matter in all patients. Contrast enhancement on CT and/or MR studies was strong in eight patients and moderate in one.

CONCLUSION

Schwannoma of the jugular foramen is characteristically a sharply demarcated, contrast-enhancing tumor, typically centered on or based in an enlarged jugular foramen with sharply rounded bone borders and a sclerotic rim. Intraosseous extension may be marked.

Paranasal sinuses and nasopharynx CT and MRI

Neoplastic disease of the nose, paranasal sinuses, the nasopharynx and the parapharyngeal space requires thorough assessment of location and extent in order to plan appropriate treatment. CT allows the deep soft tissue planes to be evaluated and provides a complement to the physical examination. It is especially helpful in regions involving thin bony structures (paranasal sinuses, orbita); here CT performs better than MRI. MRI possesses many advantages over other imaging modalities caused by its excellent tissue contrast. In evaluating regions involving predominantly soft tissue structures (ec nasopharynx and parapharyngeal space) MRI is superior to CT. The possibility to obtain strictly consecutive volume data sets with spiral CT or 3D MRI offer excellent perspectives to visualize the data via 2D or 3D postprocessing. Because head and neck tumors reside in a complex area, having a 3D model of the anatomical features may assist in the delineation of pathology. Data sets may be transferred directly into computer systems and thus be used in computer assisted surgery.

Stereotastic radiosurgery for glomus jugulare tumors

OBJECTIVES/HYPOTHESIS

Surgery is considered to be the mainstay of treatment for glomus jugulare tumors. A subset of patients are poor surgical candidates based on age, medical problems, tumor size, or prior treatment failure. The purpose of this study was to review our results with stereotactic radiosurgery (gamma knife treatment) in this group of patients, with particular attention to adverse reactions and symptom relief.

STUDY DESIGN

Retrospective review and phone survey.

METHODS

Charts were reviewed for size and location of tumor, history of previous treatment, symptoms before and after treatment, amount of radiation received, acute and late complications, and functional level before and after treatment. Pre-treatment and posttreatment magnetic resonance imaging scans were also reviewed. Identified patients were then contacted for a phone interview.

RESULTS

Eight patients were identified. Phone interviews were conducted with four patients. Four patients had failed previous treatment. Follow-up ranged from 7 to 104 months. One patient experienced an acute complication: intractable vertigo requiring hospitalization. No patient experienced delayed cranial neuropathies. No patient reported worsening of any of the following symptoms: pulsatile tinnitus, hearing loss, facial weakness, hoarseness, or difficulty swallowing. Three patients reported improvement in their pulsatile tinnitus. Two patients reported improvement in hearing loss, and one patient each reported improvement in vertigo and difficulty swallowing.

CONCLUSIONS

Preliminary results suggest that stereotactic radiosurgery is useful to control symptoms and may be delivered safely in patients with primary or recurrent glomus jugulare tumors who are poor surgical candidates.