Primary paraganglioma of the lung

There are few reported cases of primary pulmonary paraganglioma in the pathology literature. Given the historical confusion surrounding bronchial tumors, widespread use of the term "chemodectoma" and classification of these lesions as paraganglioma in an outdated World Health Organization classification of lung tumors, the recognition of tumors arising from paraganglia within the lung has not been accepted by leading authorities. We present a well-documented case of a primary pulmonary paraganglioma with typical morphologic features and a supporting immunohistochemical profile. The 0.9 cm endobronchial tumor was submucosal and composed of nests of ovoid cells with abundant eosinophilic cytoplasm, cytoplasmic vacuoles, round to oval nuclei with speckled chromatin, and occasional conspicuous nucleoli. The nests of cells were surrounded by thin-walled vascular channels and stellate spindle cells. The ovoid cells showed strong diffuse staining for chromogranin A, synaptophysin, and faint staining for S-100; they were negative for cytokeratin AE1/AE3, Cam 5.2, and epithelial membrane antigen. The stellate spindle cells stained intensely positive for S-100 protein. A critical review of reported cases of pulmonary chemodectomas and paragangliomas in the English literature features few, if any, well-documented examples. While this exceedingly rare tumor should be discerned from carcinoid tumor, it remains unknown if primary pulmonary paragangliomas behave aggressively like intra-abdominal extra-adrenal paragangliomas, or in a more indolent manner observed with extra-adrenal paragangliomas in other locations.

Pigmented composite paraganglioma-ganglioneuroma of the urinary bladder

We report a case of a pigmented composite paraganglioma-ganglioneuroma of the urinary bladder in a 70-year-old female. Grossly, the tumor measured 6.5 cm in diameter and had arisen from the base of the urinary bladder. Histologically, the tumor was composed of approximately equal components of paraganglioma and ganglioneuroma, which were partly separated and partly mixed, and intermingled with each other. There were foci of ample dark brown pigmentation in the cytoplasm of chromaffin paraganglioma cells. The pigment was Masson-Fontana-positive and had been bleached by hydrogen peroxide (H2O2). Electron microscopy showed large, abundant, pleomorphic electron-dense granules consistent with neuromelanin. In addition, there were numerous electron-dense neurosecretory-type granules. Neuromelanin, melanin or lipofuscin are occasionally observed in paragangliomas, although the occurrence of these pigments has never been described in a composite tumor originating from either adrenal medulla or extraadrenal paraganglia. To the best of our knowledge, our report represents the first case of pigmented composite paraganglioma-ganglioneuroma and expands the morphological spectrum of these unusual tumors.

Secreting vagal paraganglioma

Paragangliomas are rare tumors that derive from neural crest tissue. Vagal paragangliomas account for only 3% of all head and neck paragangliomas. Patients with vagal paragangliomas typically present with an asymptomatic neck mass and, less frequently, with cranial neuropathies. It is estimated that only 1% to 3% of all head and neck paragangliomas secrete catecholamines. The incidence of secreting vagal paragangliomas is even smaller. The diagnosis of a secreting paraganglioma involves the use of a screening test for serum catecholamines and a 24-hour urinary test for catecholamine metabolites. The identification and staging of these tumors can be performed through the use of MRI and/or CT scans and an octreotide scintigraphy. The mainstay treatment is surgical extirpation; however, preoperative medical blockade is critical to avoid a hypertensive crisis intra-operatively. We present two illustrative cases of secreting vagal paragangliomas involving a complex diagnostic and therapeutic algorithm.

[Galanin immunoreactivity in a laryngeal paraganglioma: case report and literature review]

The authors describe a case of laryngeal paraganglioma (LP) occurring in a 57-year-old-woman. To date, 70 cases have been described in the literature. It is benign and recurrences are infrequent. The differential diagnosis with typical and atypical carcinoids, hemangiopericytomas, alveolar soft-part sarcomas, medullary thyroid carcinomas, malignant melanomas and metastatic renal cell carcinomas is supported by immunohistochemistry. Moreover, this tumor shows the immunohistochemical expression of galanin, a variably expressed marker of paragangliomas that it is not expressed in carcinoid tumors. Nevertheless, our observations militate against its role as a solitary marker but advocate its use in conjunction with other antibodies for the differential diagnosis of neuroendocrine neoplasms of larynx.

Genomic imprinting and environment in hereditary paraganglioma

Hereditary paraganglioma (PGL) is characterized by the development of slow-growing and vascularized tumors in the paraganglionic system. PGL is caused by germ line heterozygous inactivating mutations in the SDHB (PGL4), SDHC (PGL3), or SDHD (PGL1) genes, which encode three of the four subunits of mitochondrial complex II (succinate dehydrogenase; SDH). Common tumor sites include the carotid body in the neck and paraganglia in the abdomen. The risk of tumor development associated with SDHD mutations is determined by the sex of the transmitting parent, because only a paternal transmission leads to tumorigenesis in the progeny. This transmission pattern suggests operation of genomic imprinting on the SDHD gene. There is also evidence that the risk of tumor development increases at higher altitudes among SDHD mutation carriers. Accordingly, the increased prevalence of SDHD mutations in the Netherlands, attributable to multiple founder mutations, has been explained in part by the low altitudes in this country, which presumably reduce gene penetrance and relax the natural selection. Thus, PGL caused by SDHD mutations represents an unusual example of an inherited monogenic tumor syndrome because the risk of tumorigenesis shows an absolute dependence on the sex of the transmitting parent and may be modified by a ubiquitous environmental factor.

Case report: patient with multiple paragangliomas treated with long acting somatostatin analogue

Paragangliomas of the head and neck are uncommon neoplasms. They are usually benign, but tend to be locally invasive. Although surgical resection remains the definitive treatment, important issues about management arise when such lesions are inoperable. Beneficial effects of octreotide treatment have already been reported in a malign paraganglioma case. Here we report a 24 year old female with familial, bilateral, multiple paraganglioma in the head and neck region, who firstly presented with pulsatile tinnitus and hearing loss in her left ear. After embolization was performed, she underwent operation twice because of the gross tumor mass. No significant change in tumor size was determined after the operations, however there were no distant metastases. Although she experienced hypertension attacks, no hormonal overproduction was found in repeated measurements. As the tumor was unresectable, new alternative therapies were sought. Octreotide scintigraphy was positive in the tumoral tissue, so we began to treat her with somatostatin analogue octreotide. After a 16 month follow up period, an improvement of the performance status, the near normalisation of attacks and stabilization of tumor growth were achieved. However, in the last three visits, she began to experience symptoms more frequently and it had been necessary to increase the octreotide dose. She is now well and being followed up. In conclusion, the beneficial effects of octreotide treatment could be quantified by clinical, tumor and scintigraphic criteria. These data suggest that octreotide can be useful in the treatment of inoperable paragangliomas.

p53 Alterations and Their Relationship to SDHD Mutations in Parasympathetic Paragangliomas

Experimental and observational evidence suggests that chronic hypoxic stimulation can induce parasympathetic paraganglioma. This is emphasized by the identification of germline mutations in genes of the mitochondrial succinate dehydrogenase enzyme complex II in hereditary paraganglioma. Because of inactivating mutations in the succinate dehydrogenase subunit B (SDHB), C (SDHC), or D (SDHD) gene, the paraganglia undergo a chronic hypoxic stimulus leading to proliferation of the paraganglionic cells. Hypoxia is a known inducer of p53 up-regulation, which triggers cell cycle arrest and apoptosis. Inactivation of the p53 pathway, by gene mutation or by MDM2 overexpression, would enable cells to escape from cell cycle arrest and apoptosis and could contribute to tumorigenesis. To determine whether p53 inactivation plays a role in paraganglioma tumorigenesis, we investigated a series of 43 paragangliomas from 41 patients (of whom 24 patients harbored a germline SDHD mutation) for mutations in p53 exons 5-8 by PCR-SSCP. In addition, these tumors were investigated for p53 and MDM2 protein expression by immunohistochemistry, and the results were compared with clinical data and the presence of SDHD mutations. No aberrations in p53 exons 5-8 were found. The immunohistochemical experiments showed nuclear p53 expression in 15 tumors. Three tumors were positive for MDM2 that were also positive for p53. There was no correlation between p53 and MDM2 expression and clinical data or SDHD status. Given the fact that hypoxia induces p53 expression and regarding the absence of p53 mutations, these results suggest that p53 inactivation does not play a major role in the tumorigenesis of hereditary and sporadic paragangliomas.

Galanin immunoreactivity in paragangliomas but not in carcinoid tumors

Galanin is a 29 to 30-amino acid neuropeptide involved in diverse regulatory effects in the central and peripheral nervous systems. Although galanin has been found in paragangliomas and other tumors, its expression has not been studied in carcinoid tumors arising in various locations. Galanin was detected in 62% (15/24) of adrenal pheochromocytomas, 40% (2/5) of jugulotympanic paragangliomas, and 18% (2/11) of carotid body paragangliomas, but was absent in 4 extra-adrenal pheochromocytomas and 3 metastatic or recurrent paragangliomas. All 26 carcinoid tumors were negative. Galanin may have limited utility as a diagnostic marker alone but would be most useful in conjunction with other immunohistochemical markers for the differential diagnosis of neuroendocrine tumors.

Subglottic laryngeal paraganglioma

OBJECTIVES

To review the clinical and pathological picture of laryngeal paragangliomas and compare laryngeal paragangliomas with the three other types of laryngeal neuroendocrine neoplasms.

STUDY DESIGN

The study presents a case review of a patient with a subglottic laryngeal paraganglioma treated at our institution, with a literature review of the laryngeal neuroendocrine neoplasms. Included is a review of all four neuroendocrine neoplasms, taking a close look at a comparison between laryngeal paragangliomas and atypical carcinoids tumors. All cases of subglottic laryngeal paragangliomas reported in the literature were also compiled and tabulated.

METHODS

The patient's record was reviewed for age, symptomatology, workup, and surgical procedures performed.

RESULTS

The patient was disease free 36 months after undergoing a tracheostomy for airway control, followed by a cricoid split for complete excision of the tumor.

CONCLUSIONS

It is important to differentiate among the four laryngeal neuroendocrine neoplasms, especially between atypical carcinoids and paragangliomas. Each tumor requires different treatments, with the former requiring a more aggressive approach. Paragangliomas must be completely excised to prevent their recurrence, and this approach should be considered a curative treatment. In addition, the immunohistochemical battery is of paramount importance in obtaining the correct pathological diagnosis.

KI-67 AND hTERT expression can aid in the distinction between malignant and benign pheochromocytoma and paraganglioma

The clinical and histopathological distinction between benign and malignant pheochromocytomas and paragangliomas is difficult, and reliable diagnostic markers are lacking. Here we have evaluated the prognostic value of human telomerase reverse transcriptase (hTERT) gene expression detected by reverse transcription PCR (RT-PCR); telomerase activity (TA) measured by TRAP (telomeric repeat amplification protocol) assay; immunohistochemical staining for Ki-67/MIB-1; and the mRNA expression of matrix metalloproteinase (MMP)-2 and EMMPRIN (extracellular matrix metalloproteinase inducer) analyzed by in situ hybridization in 32 primary pheochromocytomas or abdominal paragangliomas. hTERT was expressed in 7/11 malignant tumors (defined as presence of metastasis and/or extensive local invasion) as compared with in 2/21 benign tumors. All of the benign tumors showed <1% proliferative activity, as measured by Ki-67/MIB-1 staining. In all three patients with malignant tumors who developed metastases and/or invasive local recurrence during follow-up, the tumors were positive for either hTERT expression or Ki-67/MIB-1 immunoreactivity. TA was not a significant discriminator between benign and malignant tumors, and the value of EMMPRIN and MMP-2 as predictive markers was limited. In conclusion, the findings imply that the combined use of Ki-67/MIB-1 and hTERT, in addition to histopathology, provides a highly specific tool to identify benign pheochromocytoma and abdominal paraganglioma cases that are not at risk of developing recurrent or metastatic disease.

Clinical value of somatostatin receptor imaging in patients with suspected head and neck paragangliomas

Paragangliomas or glomus tumours of the head and neck region are rare somatostatin receptor-expressing neuroendocrine tumours. Precise preoperative diagnosis is of special importance in order to adequately weigh the potential benefit of the operation against the inherent risks of the procedure. In this study, the clinical value of somatostatin receptor imaging was assessed in 19 patients who underwent somatostatin receptor scintigraphy because of known or suspected paraganglioma of the head and neck region. The results were compared with the results of computed tomography and/or magnetic resonance imaging, histology and clinical follow-up. [(111)In-DTPA- D-Phe(1)]-octreotide scintigraphy was performed 4-6 and 24 h after i.v. injection of 140-220 MBq (111)In-octreotide. Whole-body and planar images as well as single-photon emission tomography images were acquired and lesions were graded according to qualitative tracer uptake. Somatostatin receptor imaging was positive in nine patients, identifying paragangliomas for the first time in three patients and recurrent disease in six patients. In one patient, a second, previously unknown paraganglioma site was identified. Negative results were obtained in ten patients. These patients included one suffering from chronic hyperplastic otitis externa, one with granuloma tissue and an organised haematoma, one with an acoustic neuroma, one with an asymmetric internal carotid artery, two with ectasia of the bulbus venae jugularis and one with a jugular vein thrombosis. In two patients with a strong family history of paraganglioma, individual involvement could be excluded. In only one patient did somatostatin receptor imaging and magnetic resonance imaging yield false negative results in respect of recurrent paraganglioma tissue. It is concluded that somatostatin receptor scintigraphy provides important information in patients with suspected paragangliomas of the head and neck region and has a strong impact on further therapeutic management.

[Scintigraphy by l'Octreoscan in the management of head and neck paragangliomas]

OBJECTIVE

To assess the usefulness of somatostatin receptor scintigraphy [Octreoscan] in a series of 18 patients referred for a suspicion of paraganglioma of the head and neck between July 2001 and February 2002.

PATIENTS AND METHODS

Sixteen patients had one or several paragangliomas of the head and neck diagnosed on conclusive conventional imaging including CT and MR scan. In two patients, radiological data were not conclusive. Planar images were obtained 4 and 24 hr after the iv injection of 148-185 MBq [Octreoscan].

RESULTS

Twenty-two hot spot lesions were detected. Twenty of these lesions corresponded to the twenty known paragangliomas. The volume of the smallest tumor was 0.2 cm(3). In one patient, intense thyroid nodule uptake led to the surgical diagnosis of oncocytoma. In two lesions, where conventional imaging was not conclusive, arteriography showed a typical aspect of meningioma; one patient was operated on and histology confirmed this diagnosis. No evidence of abnormal uptake was seen in site previously operated on (3 patients).

CONCLUSION

Octreotide scintigraphy is a very sensitive method for detection of paraganglioma of head and neck. It provides information on potential tumor sites in the whole body after one single injection. It could be used as a screening test in patients at risk (familial or known paraganglioma) in order to detect paraganglioma at an early stage and, thus to reduce the surgical morbidity, as well as in the follow-up after surgery to detect recurrences.

[Secreting paraganglioma of the organ of Zuckerkandl. A case report]

We report a case of a secreting retroperitoneal paraganglioma which developed on the organ of Zuckerkandl. Paraganglioma is a rare tumor of the paraganglioma system arising from undifferentiated cells of the neural crest. The originality of our observation comes from the secreting character of the tumor and the malignity proved by the local spreading to the wall of the inferior vena cava and the metastasis. The probable existence of a double primary localisation is also exceptional.

Familial malignant catecholamine-secreting paraganglioma with prolonged survival associated with mutation in the succinate dehydrogenase B gene

Approximately 10% of catecholamine-secreting tumors are malignant, and 10% are familial. These tumors have been associated with several hereditary syndromes, including multiple endocrine neoplasia type 2, von Hippel-Lindau syndrome, neurofibromatosis type 1, and familial paraganglioma. Mutations in succinate dehydrogenase (SDH) subunit genes have been identified in some kindreds with catecholamine-secreting tumors. In 1972 at the Mayo Clinic, a metastatic catecholamine-secreting paraganglioma was diagnosed in a 32-yr-old man. In 1979, 7 yr after the initial surgical treatment, a lytic metastasis to the left femur was found and was treated with local external radiotherapy. Locally metastatic abdominal catecholamine-secreting paragangliomas were diagnosed in the patient's 27-yr-old son. Analyses of the VHL, RET, SDHD, and SDHC genes revealed no mutations. However, a missense point mutation was detected in the SDHB gene: c.725G-->A in exon 7, which alters a conserved arginine at amino acid position 242 to a histidine (R242H). Sequencing of the SDHB gene in the tumors did not reveal any somatic mutations or loss of heterozygosity of the remaining allele. Thirty years after the initial diagnosis, the father is one of the longest living survivors of malignant catecholamine-secreting paraganglioma. Our findings indicate that mutations in SDHB may be associated with metastatic, yet clinically indolent, abdominal paraganglioma in some families.

Succinate dehydrogenase and human diseases: new insights into a well-known enzyme

Inherited defects of the mitochondrial succinate dehydrogenase (SDH) in humans are associated with striking variable clinical presentations ranging from early-onset devastating encephalomyopathy to tumour susceptibility in adulthood, or optic atrophy in the elderly. Although different genes encoding the four subunits of the SDH have been found mutated in association with these different phenotypes, we propose that the wide clinical spectrum actually originates from the specific roles of the SDH in the respiratory chain and the mitochondria. In particular, beside its function in the Krebs cycle and the respiratory chain, the specific redox properties of the enzyme could confer to the SDH a specific function in superoxide handling.

Growth factors and cytokines in paragangliomas and pheochromocytomas, with special reference to sustentacular cells

The aim of this study was to localize various growth factors and cytokines in paragangliomas and pheochromocytomas in order to understand their possible autocrine or paracrine functions, and to compare sustentacular cells of the adrenal medulla with pituitary stellate cells. Thirteen resected tumors, 11 paragangliomas and 2 pheochromocytomas of the adrenal medulla, were studied. In addition, five surgically removed nontumorous adrenals and five nontumorous pituitaries were studied. Varying numbers of sustentacular cells were immunopositive for S-100 protein and in most instances for glial fibrillary acidic protein. Insulin-like growth factor-1 (IGF-1), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 were localized to both cell types in all cases, whereas epidermal growth factor (EGF) immunopositivity was noted in only three. In all tumors, leukemia inhibitory factor (LIF) was restricted to chief cells and EGF receptor to sustentacular cells. Nontumorous chief cells and sustentacular cells of adrenal medulla exhibited immunoreactivities similar to those of paragangliomas and pheochromocytomas. Secretory adenohypophysial cells displayed various immunoreactivities for all growth factors, receptors, and cytokines studied. Pituitary stellate cells were immunopositive for EGF, EGF receptor, IGF-1, LIF, and TNF-alpha. In conclusion, paragangliomas and pheochromocytomas are immunoreactive for a wide spectrum of growth factors and cytokines. Immunocytochemistry demonstrated similarities between sustentacular cells and stellate cells of the pituitary in addition to their similar morphology. The significance of these observations regarding paracrine activities of chief and sustentacular cells remains to be determined.

Benign paragangliomas: clinical presentation and treatment outcomes in 236 patients

Paragangliomas are rare tumors that arise from extraadrenal chromaffin cells. We examined the clinical characteristics, location, treatment, and outcome of 236 patients (141 females, 60%) with 297 benign paragangliomas evaluated at the Mayo Clinic during 1978-1998. The mean age (+/-SD) at diagnosis was 47 +/- 16 yr. Of the 297 paragangliomas, 205 were in the head and neck region, and 92 were below the neck. Paragangliomas were discovered and diagnosed incidentally on imaging studies in 9% of patients. Biochemical screening was performed in 128 patients; 40 patients (17% of the total and 31% of those screened) had hyperfunctional tumors. Of the 40 patients with tumoral catecholamine excess, 38 had documented hypertension. In patients identified with catecholamine-secreting paragangliomas, the sensitivities achieved by measurements in the 24-h urine collection were 74% for total metanephrines, 84% for norepinephrine, 18% for dopamine, and 14% for epinephrine. Multiple imaging modalities were used for tumor localization. The false negative rates were 0% for magnetic resonance imaging, 5.8% for computed tomography, 3.4% for angiography, 10.7% for ultrasonography, and 39% for radioactive iodine-labeled metaiodobenzylguanidine scintigraphy. Of 192 patients (81.4%) with follow-up data (mean, 43.9 months; range, 0.5-240), operative cure was achieved in 133 (69%). Of the 59 patients without cure, 23 had persistent disease, 5 had recurrent disease, 16 had multiple persistent synchronous tumors, and 15 subsequently developed metachronous tumors. In conclusion, most paragangliomas are nonhypersecretory and located in the head and neck region. Magnetic resonance imaging was associated with the lowest false negative rate, and metaiodobenzylguanidine was the least sensitive imaging study. A significant proportion of patients (31%) has persistent or recurrent disease, and long-term follow-up is important.

Head and neck paragangliomas: physiology and biochemistry

Paragangliomas of the head and neck are derivatives of neural crest cells, comprising part of the diffuse neuroendocrine system. Indeed, paragangliomas encompass a unique subset of tumors of the head and neck. Their biochemistry and physiology are similar to other neuroendocrine tumors unlike tumors based on location. This article discusses their distinct biologic attributes.

[Paraganglioma of the cauda equina with papillary pattern and cytokeratin expression: 2 potential sources of diagnostic error. Report of a case and review of the literature]

Paragangliomas are unusual neuroendocrine tumours, rare in the cauda equina and filum terminale. Due to their low frequency, no classical patterns and dual immunophenotype, may be misinterpreted as others neoplasms more frequent in this site. It is our aim to report a case of paraganglioma of the cauda equina and filum terminale (PGCCFT), standing out it's histological-immunohistochemical pattern, differential diagnosis, prognostic and treatment. We reviewed the clinical presentation, NMR features and morphological aspect of one PGCCFT, diagnosed in the ABC Medical Center's Surgical Pathology Department of Mexico City. Report of the case: 26 years old man, who had been suffering a low lumbar pain for one year before he came to our hospital. The NRM showed heterointense lesion in the level of first and second vertebra, suggesting ependymoma. The tumor was totally resected. Histologically it was papillary, the chief cells have stained with chromogranin, synaptophysin, and cytokeratin. The few sustentaculars cells were S100 positive. The patient have haven a favorable course.

CONCLUSIONS

The certainty and differential diagnosis of paragangliomas of the cauda equina and filum terminale needs correlation between histological pattern and immunophenotype, the last must be considered in the peculiar context of this anatomic region.

Immunohistochemical features of paragangliomas

Immunohistochemistry is part of the routine diagnosis of the neuroendocrine tumors. In our study, we included 52 paragangliomas with various localizations by routine histology and immunohistochemistry. In order to increase the diagnostic specificity, a complex immunohistochemistry panel has been performed consisting of Bcl-2, Ki-67, Bax and Pituitary Adenylate Cyclase-Activating Peptide (PACAP), somatostatin, VIP and Calcitonin Gene Related Peptide (CGRP). After heat induced antigen retrieval, the immunostaining was performed by StreptABC using DAB as a chromogen. We were the first to demonstrate the presence of Bax and PACAP in paragangliomas. Some of the used markers are of prognostic value. The relationship between Bcl-2 and Bax is decisive in generating the final response to the input apoptotic signals. The Ki-67 antigen staining has gained wide acceptance in prognostic evaluation of other tumor types. We noted a small number of Ki-67 positive cases, which signifies a low mitotic activity of these tumors and a relatively high number of Bax positivities (32.9%) and the much lower number of Bcl-2 positivities (11.39%), and could explain the benign behaviour of paragangliomas.