Paragangliomas of the head and neck. Immunohistochemical analysis of 16 cases in comparison with neuro-endocrine carcinomas.

Sixteen cases of paragangliomas of the head and neck including 8 of the vagal body, 3 of the carotid body, 2 jugulotympanic, 2 vagal or jugulotympanic and 1 of the larynx were analysed. Clinically, 13 tumors were benign, 2 showed local aggressivity and 1 showed metastases. All tumors were tested with antisera directed against neuron-specific enolase (NSE), chromogranin A (CGA), S-100 protein, neurofilaments (NF), glial fibrillary acid protein (GFAP) and cytokeratin (CK). Immunohistochemical results were compared with those of 5 cases of neuroendocrine carcinoma (NC) (1 of the oral vestibule, 1 of the larynx, 1 Merkel-cell tumor of the skin and 2 medullary thyroid carcinomas). Immunoreactivity for NSE and/or CGA was always positive in all paragangliomas and NC. S-100 protein was positive in sustenticular cells in all cases of paragangliomas and focally in two cases of NC. NF and GFAP were focally positive in 3 and 2 paragangliomas respectively; and in 1 NC. CK was constantly negative in all cases of paraganglioma and constantly positive in all cases of NC. Antibody anti-CK is the single most useful immunomarker for differential diagnosis between paraganglioma, frequently benign neoplasms and NC commonly aggressive in the head and neck. These findings are consistent with the current concepts of the neuroendocrine system.     

Immunocytochemistry of paragangliomas—value of staining for S-100 protein and glial fibrillary acid protein in diagnosis and prognosis

Surgical specimens of 65 adrenal and 27 extra-adrenal paragangliomas, the latter comprising 11 carotid body, five jugulotympanic, one aorticopulmonary, eight aorticosympathetic and two visceral autonomic tumours, were examined immunocytochemically for the presence of glial fibrillary acid protein (GFAP) and S-100 protein. Six adrenal and four extra-adrenal (one parasympathetic and three sympathetic) neoplasms pursued a malignant clinical course. S-100 staining of sustentacular (type 2) cells was seen in both adrenal (48/65) and extra-adrenal (23/27) lesions, the 10 malignant tumours being entirely devoid of S-100 protein positive cells. GFAP positivity of type 2 cells was seen in only 16 of the extra-adrenal tumours, all of these lesions belonging to the group of benign parasympathetic paragangliomas. The presence of S-100 positive type 2 cells may thus help to exclude malignancy in individual paraganglioma cases, while GFAP positivity of such cells renders possible the correct typing of benign parasympathetic paragangliomas.     

Fibrous histiocytoma of the orbit. A clinicopathologic study of 150 cases

This is a clinicopathologic study of 150 cases of fibrous histiocytoma of the orbit. The tumors occurred in adults (median age, 43 years). The upper and nasal portions of the orbit were the most common sites of involvement. The most common signs and symptoms were proptosis (60 per cent), mass (46 per cent), and decreased vision (25 per cent). Based on the histopathologic features, the tumors were classified in three groups: benign (94 cases), locally aggressive (39 cases), and malignant (17 cases). The biological behavior correlated well with the duration of symptoms, the size and margins of the mass, and the histologic classification. The rate of recurrence was 31 per cent for the benign tumors, 57 per cent for the locally aggressive tumors, and 64 per cent for the malignant tumors. Follow-up data were obtained for 123 patients, with a mean duration of seven years. The ten-year survival of patients with benign, locally aggressive, and malignant fibrous histiocytoma was 100 per cent, 92 per cent, and 23 per cent, respectively. Nine patients died as a result of the tumor, six from local invasion of adjacent structures and three from metastatic disease. Fibrous histiocytoma is the most common primary mesenchymal orbital tumor of adults. The origin of the neoplasm is probably a primitive mesenchymal cell. Complete surgical excision appears to be the treatment of choice.     

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.     

Decreased expression of neuropeptides in malignant paragangliomas: an immunohistochemical study

Paraffin-embedded sections of 99 human adrenal and extraadrenal paragangliomas were analyzed by the indirect immunoperoxidase technique for the presence of neuron-specific enolase (NSE) and 10 neuropeptides. Each showed diffuse staining for NSE. Most tumors were positive for [Leu5]-enkephalin (76 per cent), [Met5]-enkephalin (75 per cent), somatostatin (67 per cent), and pancreatic polypeptide (51 per cent), followed by vasoactive intestinal polypeptide (VIP) (43 per cent), substance P (31 per cent), ACTH (28 per cent), calcitonin (23 per cent), bombesin (15 per cent), and neurotensin (12 per cent). The neuropeptides paralleled to a large extent those normally found in the sympathetic nervous system. Clinically malignant paragangliomas (n = 25) with proven regional or distant metastases expressed considerably fewer neuropeptides, although the spectrum of those seen remained similar. Malignant paragangliomas contained an average of two neuropeptides per tumor, in contrast to five for the benign tumors (P less than 0.05). Logistic regression analysis of staining results revealed that the paucity of enkephalins, somatostatin, pancreatic polypeptide, and VIP along with the patient's sex was predictive of clinical malignancy. Our results show a definite relationship between expression of neuropeptides and the biologic behavior of these paragangliomas.     

Malignant jugulotympanic paraganglioma

Jugulotympanic paragangliomas are neoplasms that arise in the jugular bulb (glomus jugulare tumor) or temporal bone (glomus tympanicum tumor). They are histologically similar to carotid body tumors; both are derived from extra-adrenal paraganglia. Of only 20 metastases reported, five had biopsy-proved bone involvement. We present a review of the literature of metastatic jugulotympanic paragangliomas and report a case that recurred locally with regional metastases 10 years after initial presentation and metastasized to spine 13 years later. Histologic data are reviewed, and potential treatment regimens are contrasted.     

Morphology and histogenesis of paraganglioma

Histological and ultrastructural studies were performed to examine 6 paragangliomas of various sites: carotid glomus, aortic body, sympathetic chain, and stomach. Five of the tumors in question had a histological structure typical of a paraganglioma. The gastric tumor was distinguished by being similar to a pheochromocytoma. With regard to the degree of infiltrative growth, the paragangliomas of the sympathetic chain and stomach were regarded as malignant. The ultrastructures of the paragangliomas examined were found to be of the same type. In all the neoplasms, tumor cells had signs of neuroendocrine and neurogenous differentiations that were characteristic of the ultrastructural organization of postganglionic neurons in the autonomic nervous system. The neurogenous differentiation was evidenced by cytoplasmic portions that are structurally similar to rough-surface endoplasmic reticulum, which is pertaining to Nissl's bodies; neurofilaments that form concentric structures containing neuroendocrine granules such as fibrous or Pick's bodies; intracytoplasmic cilia; specialized cytoplasmic processes of two types: axons and dendrites; partially reduced intercellular contacts, such as axosomatic and axodendritic synapses; sustentacular cells (sustenocytes). In the neoplasms evaluated as malignant, the neurogenous differential signs were more pronounced by reducing the number of neurosecretory granules, which might, apparently, serve as an ultrastructural criterion for establishing the degree of paraganglioma malignancy.     

Tumoren des Nebennierenmarks und der Paraganglien

The sympathetic and parasympathetic paraganglia are the site of pheochromocytomas and paragangliomas. The adrenal pheochromocytoma and the abdominal paraganglioma derive from the sympathetic nervous system. The parasympathetic paragangliomas are predominantly localized in the head and neck region. Most pheochromocytomas are hormonally active and benign. The abdominal paragangliomas usually correspond to adrenal pheochromocytomas, but are more commonly malignant. The parasympathetic paragangliomas are usually benign, hormonally inactive and are most commonly located in the bifurcation of the carotid artery.     

Vesicular monoamine transporter 2 as a marker of gastric enterochromaffin-like cell tumors

The vesicular monoamine transporter 2 (VMAT2) facilitates the ATP-dependent accumulation of biogenic amine inside the secretory granules of endocrine cells and neurons and was demonstrated in the histamine-producing enterochromaffin-like (ECL) cells of the stomach. In the present investigation, VMAT2 immunohistochemistry was tested in 85 endocrine tumors, of which 60 were well differentiated gastrointestinal and pancreatic growths, 5 poorly differentiated (neuro)endocrine carcinomas (PDEC) and 1 mixed PDEC/ECL cell carcinoma of the stomach, 12 pheochromocytomas/paragangliomas, 3 adrenocortical lesions, 2 parathyroid and 2 lung neuroendocrine tumors. Extensive and intense VMAT2 immunoreactivity was observed in 16 of 16 gastric ECL cell tumors, 6 of 6 adrenal pheochromocytomas, 2 of 2 chromaffin paragangliomas and in 3 of the 4 carotid body paragangliomas investigated. Rare VMAT2-positive cells were observed in 12 of 21 intestinal enterochromaffin (EC) cell tumors, in 9 of 11 pancreatic neuroendocrine tumors, and in the mixed PDEC/ ECL cell carcinoma of the stomach (differentiated cells only). No VMAT2 immunoreactivity was observed in five gastrin, four somatostatin and three enteroglucagon/peptideYY tumors of the gastrointestinal tract, in six gastric PDECs, in three adrenocortical growths, and two parathyroid and two lung neuroendocrine tumors. These data support VMAT2 immunohistochemistry as being a useful tool for the diagnosis of gastric ECL cell tumors, separating them from all other endocrine tumors arising in the gastroduodenal area i.e., gastrin, somatostatin, EC cell and PDEC tumors, all of which proved essentially negative. Received: 28 June 1999 / Accepted: 20 October 1999     

Prediction of malignant behavior of pheochromocytomas and paragangliomas using immunohistochemical techniques

Pheochromocytomas and paragangliomas arise from the adrenal glands and extraadrenal paraganglia, respectively. Malignant behavior of these tumors is uncommon and is, in part, dependent on their sites of origin, such as extraadrenal location. Morphologic criteria for malignancy of pheochromocytoma and paragangliomas have not been clearly defined. In this study, to clarify the histologic features that distinguish the benign from malignant pheochromocytomas and paragangliomas, we examined metastatic and nonmetastatic tumors using immunohistochemical techniques. A total of eight cases, five pheochromocytomas from the adrenal glands (four benign and one malignant tumor) and three paragangliomas with invasion or metastasis, were studied. The markers used in this study were chromogranin A, synaptophysin, NCAM (CD56), SNAP25, neuron-specific enolase, S-100 protein, and MIB-1. Our results suggest that MIB-1 immunostaining is a useful adjunct marker to predict malignant behavior in these tumors.     

Paragangliomas of the Head and Neck: Ultrastructural and Immunohistochemical Analysis

Eighteen head and neck paragangliomas were studied by light microscopy and light microscopic immunohistochemistry by the peroxidase technique for the presence of NSE (neuron-specific enolase), serotonin, and a battery of neuropeptides. Seven of these tumors were also studied by electron microscopy.

All 18 cases demonstrated immunostaining for NSE; 10 of the 11 carotid body tumors had immunostaining for multiple hormones. Considering all 18 cases, the most frequently demonstrated hormonal substances were in order: serotonin, leuenkephalin, gastrin, substance P, vasoactive intestinal polypeptide (VIP), somatostatin, bombesin, calcitonin, and alpha MSH. In several tumors, adjacent-step sections stained for different hormonal substances strongly suggested reactivity for more than one hormone in given tumor cells.

By electron microscopy, all 7 cases studied displayed considerable heterogeneity of the neurosecretory granules with respect to size, shape, and electron density. This demonstrated that branchiomeric paragangliomas are capable of producing a spectrum of neuropeptides in addition to their known amine content. The presence of immunoreactive serotonin in most of these neoplasms was confirmed. In addition to these findings, neurofibrils within the substance of carotid body paragangliomas demonstrated immunoreactivity for somatostatin and a gastrinlike neuropeptide. The significance of the neuropeptides in these neoplasms and their possible presence and role in normal and hyperplastic paraganglia remain to be defined.     

Paragangliomas of the Head and Neck: Ultrastructural and Immunohistochemical Analysis

Eighteen head and neck paragangliomas were studied by light microscopy and light microscopic immunohistochemistry by the peroxidase technique for the presence of NSE (neuron-specific enolase), serotonin, and a battery of neuropeptides. Seven of these tumors were also studied by electron microscopy.

All 18 cases demonstrated immunostaining for NSE; 10 of the 11 carotid body tumors had immunostaining for multiple hormones. Considering all 18 cases, the most frequently demonstrated hormonal substances were in order: serotonin, leuenkephalin, gastrin, substance P, vasoactive intestinal polypeptide (VIP), somatostatin, bombesin, calcitonin, and alpha MSH. In several tumors, adjacent-step sections stained for different hormonal substances strongly suggested reactivity for more than one hormone in given tumor cells.

By electron microscopy, all 7 cases studied displayed considerable heterogeneity of the neurosecretory granules with respect to size, shape, and electron density. This demonstrated that branchiomeric paragangliomas are capable of producing a spectrum of neuropeptides in addition to their known amine content. The presence of immunoreactive serotonin in most of these neoplasms was confirmed. In addition to these findings, neurofibrils within the substance of carotid body paragangliomas demonstrated immunoreactivity for somatostatin and a gastrinlike neuropeptide. The significance of the neuropeptides in these neoplasms and their possible presence and role in normal and hyperplastic paraganglia remain to be defined.     

Basic fibroblast growth factor and fibroblastic growth factor receptor-1 may contribute to head and neck paraganglioma development by an autocrine or paracrine mechanism

Paragangliomas are hypervascular tumors arising from neural crest-derived paraganglia that are associated with the autonomic nerve system. Mutations in genes coding for subunits of mitochondrial complex II are associated with hereditary paragangliomas, and it has been suggested that these mutations result in a pseudohypoxic signal triggering tumorigenesis. Fibroblastic growth factors are hypoxia-inducible angiogenic stimuli that are involved in the angiogenesis and tumorigenesis of several neoplasms. It has been demonstrated that basic fibroblastic growth factor (bFGF) is a survival factor for cultured chief cells of the carotid body, capable of inducing proliferation. To examine the role of this growth factor in paragangliomas, we studied the immunohistochemical expression of bFGF and its high affinity receptor fibroblastic growth factor receptor 1 (FGFR1) in 7 normal carotid bodies and in 33 head and neck paragangliomas, including 2 malignant cases and their metastases. Immunohistochemical expression of bFGF and FGFR1 in tumors was confirmed by real-time polymerase chain reaction. FGFR1 was moderately present in carotid bodies, and there was strong and significantly enhanced cytoplasmatic staining of FGFR1 in all paragangliomas. Chief cells in carotid bodies and tumors showed strong cytoplasmatic staining for bFGF. The results indicate that FGFR1 and bFGF may contribute to the development of head and neck paragangliomas.     

Tissue culture, electron microscopic and enzyme histochemical investigations of extraadrenal paragangliomas.

Light and electromicroscopical as well as histochemical investigations were performed on three cases of extraadrenal paragangliomas. They were localized in the carotid body, tympanicum and cauda equina region. Tissue of two cases was cultivated in vitro in nutrient medium TCM 199. The tumours were classified as paragangliomas of the paraganglionic type with typical cell clusters, of the adenomatous and angiomatous type. The enzyme histochemistry showed a very high dehydrogenase activity. Ultrastructurally numerous typical osmiophilic granules could be observed in the cytoplasm of the tumour cells. In tissue culture only a minimal cellular proliferative activity could be detected. The few proliferating cell colonies showed mostly characteristics of epithelial tissue and sometimes a similar behaviour to cells of a ganglioneuroblastoma. The minimal proliferative activity in vitro is in good agreement with the proliferative behaviour of the extraadrenal paragangliomas in vivo.     

Somatostatin-receptor imaging in the localization of endocrine tumors

BACKGROUND AND METHODS. A number of different tumors have receptors for somatostatin. We evaluated the efficacy of scanning with 123I-labeled Tyr3-octreotide, a somatostatin analogue, for tumor localization in 42 patients with carcinoid tumors, pancreatic endocrine tumors, or paragangliomas. We then evaluated the response to octreotide therapy in some of these patients. RESULTS. Primary tumors or metastases, often previously unrecognized, were visualized in 12 of 13 patients with carcinoid tumors and in 7 of 9 patients with pancreatic endocrine tumors. The endocrine symptoms of these patients responded well to therapy with octreotide. Among 20 patients with paragangliomas, 8 of whom had more than one tumor, 10 temporal (tympanic or jugular), 9 carotid, and 10 vagal tumors could be visualized. One small tympanic tumor and one small carotid tumor were not seen on the scan. CONCLUSIONS. The 123I-labeled Tyr3-octreotide scanning technique is a rapid and safe procedure for the visualization of some tumors with somatostatin receptors. A positive scan may predict the ability of octreotide therapy to control symptoms of hormonal hypersecretion.     

A review of the histology, ultrastructure, immunohistology, and molecular biology of extra-adrenal paragangliomas

This review summarizes our understanding of extra-adrenal paragangliomas, a subject that has evolved considerably during the past several years. Our object was to review the anatomical, histologic, and biological features of normal and neoplastic glands, with emphasis on immunohistologic studies, and briefly discuss the potential application of nucleic acid hybridization. Since it is difficult to predict clinical outcome for patients with paragangliomas, we have emphasized the differences between benign and malignant paragangliomas, concentrating on recent results obtained using immunohistologic techniques. These studies have emphasized the critical importance of the identification, by immunohistologic means, of two distinct cell populations, chief cells (type I) and sustentacular cells (type II). The relationship between these two cell populations, stable in normal glands and benign tumors, is progressively lost in tumors of increasing degrees of malignancy, sustentacular cells being absent from the most progressively metastasizing paragangliomas.     

Histopathology of benign versus malignant sympathoadrenal paragangliomas: clinicopathologic study of 120 cases including unusual histologic features

The clinical and pathologic features of 120 adrenal and extraadrenal paragangliomas were studied in an attempt to identify features which might predict malignant behavior. Clinical follow-up was obtained in 98 cases (82%); 64 tumors were clinically benign, and 34 were malignant as evidenced by regional or distant metastases and/or extensive local invasion. Thirty-two of the 34 malignant tumors (94%) were functionally active. Features noted more frequently in malignant tumors included male predominance (74%; P2 [two-sided P value] = .002), extraadrenal location (52%; P2 less than .0001), greater tumor weight (mean 383 g versus 73 g for nonmalignant tumors), confluent tumor necrosis, and the presence of vascular invasion and/or extensive local invasion. Intracytoplasmic hyaline globules were seen in 59% and 32% of benign and malignant tumors, respectively (P2 = .001). Logistic regression analysis of 16 nonhistologic and histologic parameters showed four of them to be most predictive of malignancy--extraadrenal location, coarse nodularity of the primary tumor, confluent tumor necrosis, and absence of hyaline globules. Most malignant paragangliomas had two or three of these features (71%), while 89% of benign tumors had only one (or none; P less than .0001). According to the statistical model developed, there was better than a 95% probability that more than 70% of tumors could be classified correctly on the basis of the four factors indicated. Although limitations still exist, results of this study provide some basis for evaluating malignant potential of these tumors.     

Familial Cervical Paragangliomas with Lymph Node Metastasis Expressing Somatostatin Receptor Type 2A

We report a case of familial, bilateral cervical paragangliomas (PGs) with lymph node metastasis. Patient I-1 is a 56-year-old man with a right carotid body tumor and a left vagal PG. Patient II-1 is a 29-year-old woman and the daughter of Patient I-1; she had a left carotid body tumor with regional lymph node metastasis. Histology of all the tumors showed the typical pattern of PGs, i.e., a zellballen pattern composed of chief cells positive for chromogranin A, and sustentacular cells positive for S100 protein. The Ki-67 labeling index was 1% to 3% in these PGs in both the primary and the metastatic tumors. Immunohistochemical analysis showed expression of somatostatin receptor (sstr) type 2A, but was negative for sstr type 5. Genomic mutation in succinate dehydrogenase type D was confirmed in both patients. Here, we present a case of familial PGs, and discuss the cases with special reference to pathologic diagnosis, genetics, and treatment.     

Gastrointestinal autonomic nerve tumors. 'Plexosarcomas'

Four plexosarcomas (gastrointestinal autonomic nerve tumors) characterized by light microscopic, immunocytochemical, and ultrastructural examination, including immunoelectron microscopy in one case, are described. The four neoplasms occurred in the small intestine (duodenum, two; jejunum, one; and ileum, one) and they had an aggressive course with either local or distant metastases. The light-microscopic patterns varied from epithelioid and organoid to spindle cells, mimicking endocrine and sarcomatous neoplasms. Ultrastructurally, these tumors exhibited interdigitating cytoplasmic processes that contained scattered aggregates of membrane-bound granules varying in size from 100 to 300 nm intermixed with empty vesicles and numerous diffusely distributed intermediate filaments. Basal lamina covering cell surfaces, attachment plaques, and myofilaments, as expected in smooth-muscle tumors, were not identified, and diffusely distributed membrane-bound granules, as seen in paragangliomas and carcinoid tumors, were also absent. By immunocytochemistry, the tumors were intensely positive for vimentin and neuron-specific enolase and focally positive for neurofilaments and synaptophysin. In addition, three tumors were S100 protein positive and one stained for vasoactive intestinal peptide. Similar positive immunocytochemical reactions were identified in normal enteric plexus. It is essential to recognize plexosarcomas, which are invariably accompanied by aggressive clinical behavior, in spite of a seemingly benign, mitotically inactive light-microscopic appearance in most instances. Ultrastructural examination can readily separate plexosarcomas from paragangliomas and other sarcomatous and endocrine neoplasms.