Chemodectoma of the orbit

Orbital Paraganglioma: A Systematic Review

Purpose  The purpose of this study was to perform a systematic review of the literature on orbital paragangliomas, evaluating clinical presentation, diagnosis, management patterns, and prognosis. Methods  The systematic review was conducted based on the principles described in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. PubMed, Cochrane databases, Embase, and Web of Science were searched for articles related to orbital paragangliomas. Inclusion criteria included English language articles with original reports on human subjects. Data on clinical presentation, diagnosis, treatment, and prognosis were collected. Results  Twenty-seven articles met inclusion criteria (28 total patients). The mean patient age was 37.1 years (range, 3-75 years); 13 (46.4%) patients were male. The most common presenting symptoms were proptosis (89.2%), visual acuity changes (67.9%), and extraocular muscle restriction (64.2%). Lesions were most commonly intraconal (92.9%). Single modality therapy was employed in 19 patients (67.9%), including excision in 12 patients (42.9%) and exenteration in 5 patients (17.9%). Ten patients (35.7%) developed recurrence, and there was a 92.9% survival rate (mean follow-up, 29 months). Conclusion  Orbital paragangliomas are rare tumors with an excellent prognosis. These lesions commonly present with proptosis, and are primarily managed surgically with simple excision, although exenteration and adjuvant radiation may be necessary for invasive tumors. This series is the largest and most comprehensive systematic review of orbital paragangliomas conducted to date.

Orbital paraganglioma: case report and review of the literature

Paragangliomas of the orbit are extremely rare. A case of an orbital paraganglioma, including the first magnetic resonance imaging description of this tumour is described here. The patient underwent surgery with gross total removal of the tumour and relief of his initial chief complaint of visual blurring. The differential diagnosis and therapeutic options for the management of this tumour are discussed.

Paraganglioma of the thyroid

We present a case of paraganglioma of the thyroid. The preoperative evaluation, surgical management, and histopathology are described. Four similar cases that have been reported are summarized, and a hypothesis for the origin of a paraganglioma within the thyroid capsule is proposed.

Histopathology, cytology and cytochemistry of pheochromocytomas and paragangliomas including chemodectomas

The results of histopathological, histochemical and ultrastructural investigations on pheochromocytomas and paragangliomas have been reported. These results allowed the functional identification of the cell types composing many of such tumours. Moreover, comparison of these data with clinico-pathologic findings outlined the advantages and limits of cytologic studies for understanding the natural history of pheochromocytomas and paragangliomas and improving our diagnostic and prognostic criteria.

Paraganglioma of the cauda equina region. Clinicopathologic study of 31 cases with special reference to immunocytology and ultrastructure

Thirty-one paragangliomas of the cauda equina region were studied (18 men and 13 women, ages 30-71 years [mean, 51 years]). Symptoms (1 day to 15 years in duration; mean, 48 months) included low back pain (87%), sensory/motor deficits (35%), urinary/fecal incontinence (13%), and paraplegia (6%). All patients studied had some myelographic block. Cerebrospinal fluid protein level ranged from 56 to 7000 mg/dl (mean, 1109 mg/dl). Most tumors were limited to the filum terminale, although one also involved the conus medullaris and two clearly arose from a caudal nerve root. All but one were entirely intradural. The tumor was totally excised in 26 cases; these patients remain disease-free. Of three patients whose tumors were excised subtotally, two received radiotherapy; the one non-radiated patient died of tumor-related complications. No autopsy was performed. One partially encapsulated tumor that had been subjected to biopsy and irradiation presented 1 year later with osseous invasion and retroperitoneal extension; 20 years after subtotal excision, this patient is alive but paraplegic. Morphologically, all tumors resembled paraganglioma at other sites. Cytologic atypia and mitotic activity generally were absent to mild. Fourteen (45%) cases showed ganglionic differentiation. All tumors tested were immunoreactive for neuron-specific enolase and neurofilament protein, and most showed somatostatin or serotonin reactivity. S-100 protein immunoreactivity was noted in sustentacular cells and, to a lesser extent, within chief cells and neurons. The authors conclude that paragangliomas are largely benign and encapsulated and respond to simple resection. When surgically feasible, gross total removal should be the goal of surgery. When subtotal resection is necessary or when local invasion leaves a question as to completeness of tumor removal, irradiation seems mandatory although far from guaranteeing prevention of recurrence. Biopsy alone is undesirable.

Malignant carotid body tumors: report of two cases and review of the literature

Paragangliomas may arise in any area of the body where nonchromaffin paraganglia are situated. These include the glomus jugulare, the carotid body, and the retroperitoneum. Malignant behavior of these paragangliomas has been a controversial subject with most authors, who consider them to be benign tumors. Some authors have diagnosed locally recurrent and infiltrative tumors as malignant, whereas most require the demonstration of metastatic potential as the only criterion for malignancy. Two cases of metastasizing carotid body tumors are reported with a review of the literature on this unusual neoplasm.

Nonchromaffin paraganglioma (chemodectoma) of thyroid region

A case of a paraganglioma located over the thyroid cartilage in the midline is reported. The tumor had all the appearances of a carotid body tumor, but its odd location could not be explained on the basis of previously known areas where paraganglionic tissues have been found. Since a paraganglioma has also hitherto been described within the thyroid gland, clinicians and pathologists alike are cautioned that unusually located paragangliomas may be expected in the future.

Chemodectoma of the orbit

The histological and clinical features of a primary chemodectoma arising in the orbit are described. It is suggested that the tumour may have arisen from chemoreceptor tissue in the area of the lacrimal gland.