Pigmented composite paraganglioma-ganglioneuroma of the urinary bladder

Paraganglioma with High Levels of Dopamine, Dopa Decarboxylase Suppression, Dopamine β-hydroxylase Upregulation and Intra-tumoral Melanin Accumulation: A Case Report with a Literature Review

Object Exclusively dopamine-producing pheochromocytoma/paraganglioma (PPGL) is an extremely rare subtype. In this condition, intratumoral dopamine β-hydroxylase (DBH), which controls the conversion of norepinephrine from dopamine, is impaired, resulting in suppressed norepinephrine and epinephrine production. However, the rarity of this type of PPGL hampers the understanding of its pathophysiology. We therefore conducted genetic and immunohistological analyses of a patient with an exclusively dopamine-producing paraganglioma. Methods Paraganglioma samples from a 52-year-old woman who presented with a 29.6- and 41.5-fold increase in plasma and 24-h urinary dopamine, respectively, but only a minor elevation in the plasma norepinephrine level was subjected to immunohistological and gene expression analyses of catecholamine synthases. Three tumors carrying known somatic PPGL-related gene variants (HRAS, EPAS1) were used as controls. Whole-exome sequencing (WES) was also performed using the patient's blood and tumor tissue. Results Surprisingly, the protein expression of DBH was not suppressed, and its mRNA expression was clearly higher in the patient than in the controls. Furthermore, dopa decarboxylase (DDC), which governs the conversion of 3,4-dihydroxyphenyl-L-alanine (L-DOPA) to dopamine, was downregulated at the protein and gene levels. In addition, melanin, which is synthesized by L-DOPA, accumulated in the tumor. WES revealed no PPGL-associated pathogenic germline variants, but a missense somatic variant (c.1798G>T) in CSDE1 was identified. Conclusion Although pre-operative plasma L-DOPA was not measured, our histological and gene expression analyses suggest that L-DOPA, rather than dopamine, might have been overproduced in the tumor. This raises the possibility of pathophysiological heterogeneity in exclusively dopamine-producing PPGL.

Paraganglioma (pheochromocytoma) of the urinary bladder: A systematic review with a diagnostic, management and treatment algorithm

Introduction:

Paraganglioma of the urinary bladder is a rare but well-documented tumour. Herein, we provide the largest, comprehensive systematic review of the literature and aim to increase familiarity with this rare but significant neoplasm.

Methods:

A systematic review of the literature was conducted on the NCBI PubMed database. The search criteria were not limited to any specific years or languages. There were 418 articles between January 1953 and August 2020, of which 255 case reports were selected.

Results:

Paragangliomas of the urinary bladder most commonly occurred in Caucasians in the fifth decade of life, most commonly presenting with haematuria and variations of ‘micturition attacks’. Eighty percent of tumours were functionally active. The mucosa was normal in 91% of patients. In all, 25% of tumours were treated with transurethral resection alone, 65% had partial cystectomy and 5% had radical cystectomy. Alpha-blockers were administered pre-operatively in 38% of patients and the risk of intra-operative hypertensive crisis was over three times greater in those who did not receive an alpha-blocker. The tumour was confined to the bladder in 75% of cases. Metastasis occurred in 20% of cases, most commonly to iliac nodes. The mean follow-up time was 26.5 months. In cases that documented follow-up, 18.6% had recurrence, most commonly in lymph nodes and bone.

Conclusion:

All patients presenting with micturition attacks or haematuria with a computed tomography showing an enhancing, well-defined submucosal bladder lesion and/or cystoscopy showing a lesion with normal overlying mucosa should be worked up for a possible paraganglioma of the urinary bladder.

Level of evidence:

Not applicable

Composite pheochromocytoma/paraganglioma-ganglioneuroma: analysis of SDH and ATRX status, and identification of frequent HRAS and BRAF mutations

INTRODUCTION

Composite pheochromocytoma/paraganglioma (CP) is a rare neoplasm with most cases presented as single reports. Little is known about its pathogenesis and relationship with ordinary pheochromocytoma (PCC) or paraganglioma (PGL). Our study is aimed at analyzing the status of SDH and ATRX and identifying novel genetic changes in CP.

METHODS

Eighteen CP cases were collected. SDH and ATRX status was screened by immunohistochemistry. Targeted region sequencing (TRS) was successfully performed on formalin-fixed paraffin-embedded tissues in two cases within 3 years. Based on the TRS result, Sanger sequencing of BRAF and HRAS was performed in fifteen cases (including the two cases with TRS performed), with three cases excluded due to the limited amount of tissue.

RESULTS

Histopathologically, all the cases were composite PCC/PGL-ganglioneuroma (GN). The GN components were either closely admixed or juxtaposed with the PCC/PGL components, with a highly variable percentage (10-80%). All cases stained positive for SDHB and ATRX. HRAS and BRAF mutations were identified during TRS. In the subsequent Sanger sequencing, 20.0% (3/15) harbored BRAF mutations (K601E and K601N) and 46.7% (7/15) harbored HRAS mutations (Q61R, Q61L, G13R). The mutation rates were both significantly higher than reported in ordinary PCC/PGL.

CONCLUSIONS

We demonstrated that composite PCC/PGL-GN might be a unique entity with frequent HRAS and BRAF mutations rather than genetic changes of SDH and ATRX. Our findings revealed the possible pathogenesis of composite PCC/PGL-GN and provided clues for potential treatment targets.

Composite Paraganglioma: Pioneering in the Head and Neck

Composite paragangliomas are rare with less than 20 cases documented in the abdomen, retroperitoneum, and urinary bladder. In this article, we report the first case of composite paraganglioma in the head and neck presenting as a soft tissue mass in the neck adjacent to the carotid artery in a 50-year-old woman. We discuss the clinicopathologic findings and genetic implications, and we review the literature of this rare entity.

Update on Adrenal Tumours in 2017 World Health Organization (WHO) of Endocrine Tumours

The fourth edition of the World Health Organization (WHO) classification of endocrine tumours contains substantial new findings for the adrenal tumours. The tumours are presented in two chapters labelled as "Tumours of the adrenal cortex" and "Tumours of the adrenal medulla and extra-adrenal paraganglia." Tumours of the adrenal cortex are classified as cortical carcinoma, cortical adenoma, sex cord stromal tumours, adenomatoid tumour, mesenchymal and stromal tumours (myelolipoma and schwannoma), haematological tumours, and secondary tumours. Amongst them, schwannoma and haematological tumours are newly documented. The major updates in adrenal cortical lesions are noted in the genetics of the cortical carcinoma and cortical adenoma based on the data from The Cancer Genome Atlas (TCGA). Also, a system for differentiation of oncocytoma from oncocytic cortical carcinoma is adopted. Tumours of the adrenal medulla and extra-adrenal paraganglia comprise pheochromocytoma, paraganglioma (head and neck paraganglioma and sympathetic paraganglioma), neuroblastic tumours (neuroblastoma, nodular ganglioneuroblastoma, intermixed ganglioneuroblastoma, and ganglioneuroma), composite pheochromocytoma, and composite paraganglioma. In this group, neuroblastic tumours are newly included in the classification. The clinical features, histology, associated pathologies, genetics, and predictive factors of pheochromocytoma and paraganglioma are the main changes introduced in this chapter of WHO classification of endocrine tumours. The term "metastatic pheochromocytoma/paraganglioma" is used to replace "malignant pheochromocytoma/paraganglioma." Also, composite pheochromocytoma and composite paraganglioma are now documented in separate sections instead of one. Overall, the new classification incorporated new data on pathology, clinical behaviour, and genetics of the adrenal tumours that are important for current management of patients with these tumours.

Primary Melanotic Paraganglioma of Thyroid Gland: Report of a Rare Case With Clinicopathologic and Immunohistochemical Analysis and a Literature Review

Background:

Pigmented paraganglioma is a special type of paraganglioma, and it is rare in the thyroid.

Case Presentation:

We report a case of a 41-year-old woman who had complained of a mass in the thyroid gland. Histology revealed tumor cells arranged in a nest-like or organoid pattern, separated by delicate fibrovascular septa. Two distinct components were observed. In the first, which constituted the majority of the tumor cells, no pigments were observed. In the second, a few cells with pigment showed intercellular substance, but the structure was unclear. Using immunohistochemistry, cells in the first component were confirmed to be diffuse strong positive for synaptophysin, but negative for chromogranin A, pan-cytokeratin, calcitonin, and thyroglobulin. About 1% of tumor cells were stained by Ki-67. In the margins of the tumor, a few cells were observed to be positive for HMB-45 and Melan A after bleaching by oxalic acid. The stromal cells were positive for S-100. Using electron microscopy, a few cells containing many round melanin bodies with greater electron density granules of nonuniform size were observed. The diagnosis of primary melanotic paraganglioma of the thyroid gland was made.

Conclusion:

Primary melanotic paraganglioma of the thyroid gland is a rare, low malignant potential tumor. To the best of our knowledge, this is the first case described.

Pigmented Lesions of the Nervous System and the Neural Crest: Lessons From Embryology

Neurosurgeons encounter a number of pigmented tumors of the central nervous system in a variety of locations, including primary central nervous system melanoma, blue nevus of the spinal cord, and melanotic schwannoma. When examined through the lens of embryology, pigmented lesions share a unifying connection: They occur in structures that are neural crest cell derivatives. Here, we review the important progress made in the embryology of neural crest cells, present 3 cases of pigmented tumors of the nervous system, and discuss these clinical entities in the context of the development of melanoblasts. Pigmented lesions of the nervous system arise along neural crest cell migration routes and from neural crest-derived precursors. Awareness of the evolutionary clues of vertebrate pigmentation by the neurosurgical and neuro-oncological community at large is valuable for identifying pathogenic or therapeutic targets and for designing future research on nervous system pigmented lesions. When encountering such a lesion, clinicians should be aware of the embryological basis to direct additional evaluation, including genetic testing, and to work with the scientific community in better understanding these lesions and their relationship to neural crest developmental biology.

Somatic RET mutation in a patient with pigmented adrenal pheochromocytoma

Pheochromocytomas (PCC) and paraganglioma (PGL) are rare neuroendocrine tumors arising from chromaffin cells of the neural crest. Mutations in the RET-proto-oncogene are associated with sporadic pheochromocytoma, familial or sporadic medullary thyroid carcinoma (MTC) and multiple endocrine neoplasia type 2. In the past, only few cases of pigmented PCCs, PGLs, and one case of pigmented MTC have been reported in the literature. Herein, we present the case of a 77-year old woman with a history of Tako-tsubo-cardiomyopathy and laboratory, as well as radiological, high suspicion of pheochromocytoma, who underwent left-sided adrenalectomy. The 3 cm tumor, which was located on the upper pole of the left adrenal, appeared highly pigmented with dark red to black color. Histologic examinations revealed highly pleomorphic cells with bizarre, huge hyperchromatic nuclei, that immunohistochemically were positive for chromogranin A and synaptophysin, focally positive for HMB45 and negative for melan A. These clinical and pathological features led to the diagnosis of the rare variant of a melanotic 'black' pheochromocytoma. In our case a somatic RET mutation in exon 16 (RET c.2753T>C, p.Met918Thy) was detected by targeted next generation sequencing. In summary, this case represents a rare variant of catecholamine-producing tumor with distinct histological features. A potential relationship between the phenotype, the cellular origin and the genetic alterations is discussed.

LEARNING POINTS

Pheochromocytoma is a rare neuroendocrine tumor.Pigmentation is seen in several types of tumors arising from the neural crest. The macroscopic black aspect can mislead to the diagnosis of a metastasis deriving from a malignant melanoma.RET mutation are seen in catecholamine and non-catecholamine producing tumors of the same cellular origin.

Paragangliomas: update on differential diagnostic considerations, composite tumors, and recent genetic developments

Recent developments in molecular genetics have expanded the spectrum of disorders associated with pheochromocytomas (PCCs) and extra-adrenal paragangliomas (PGLs) and have increased the roles of pathologists in helping to guide patient care. At least 30% of these tumors are now known to be hereditary, and germline mutations of at least 10 genes are known to cause the tumors to develop. Genotype-phenotype correlations have been identified, including differences in tumor distribution, catecholamine production, and risk of metastasis, and types of tumors not previously associated with PCC/PGL are now considered in the spectrum of hereditary disease. Important new findings are that mutations of succinate dehydrogenase genes SDHA, SDHB, SDHC, SDHD, and SDHAF2 (collectively "SDHx") are responsible for a large percentage of hereditary PCC/PGL and that SDHB mutations are strongly correlated with extra-adrenal tumor location, metastasis, and poor prognosis. Further, gastrointestinal stromal tumors and renal tumors are now associated with SDHx mutations. A PCC or PGL caused by any of the hereditary susceptibility genes can present as a solitary, apparently sporadic, tumor, and substantial numbers of patients presenting with apparently sporadic tumors harbor occult germline mutations of susceptibility genes. Current roles of pathologists are differential diagnosis of primary tumors and metastases, identification of clues to occult hereditary disease, and triaging of patients for optimal genetic testing by immunohistochemical staining of tumor tissue for the loss of SDHB and SDHA protein. Diagnostic pitfalls are posed by morphological variants of PCC/PGL, unusual anatomic sites of occurrence, and coexisting neuroendocrine tumors of other types in some hereditary syndromes. These pitfalls can be avoided by judicious use of appropriate immunohistochemical stains. Aside from loss of staining for SDHB, criteria for predicting risk of metastasis are still controversial, and "malignancy" is diagnosed only after metastases have occurred. All PCCs/PGLs are considered to pose some risk of metastasis, and long-term follow-up is advised.

Composite paraganglioma and ganglioneuroma in the retroperitoneum: a case report

Reports of a composite paraganglioma (PG) and ganglioneuroma (GN) in the retroperitoneum are rare. In the present case, dynamic computed tomographic (CT) findings showed a 30 × 22 × 20 mm tumor that was located in the retroperitoneum and which was dissociated from pancreatic tissue and the left adrenal gland. The markedly reddish tumor showed a clear margin and central multicystic changes on the cut surface. The tumor was composed of two major components, the PG and the GN. The paraganglionic cells in the PG component, which were arranged in a nested pattern, occupied the main and central part of the tumor. Both ganglionic cells and Schwann cells in the GN were located in a unorganized pattern in the periphery. The paraganglionic cells exhibited a Zellballen pattern, which consisted of an association of edematous vascular-rich stroma and focal hemorrhage, resulting in multicystic changes. These centrally located tumor cells were pleomorphic in part and did not have mitotic figures. In the periphery, Schwann cells, which were arranged in an obscure and fascicular pattern that was intermingled with large ganglionic cells, were located adjacent to the PG component with a mostly sharp margin. With higher magnification, the border was not as sharp, as revealed especially with chromogranin-A immunostain, in which both the PG and GN components were focally intermingled with each other. The histogenesis of the composite PG and GN was thought to be extraadrenal neural crest cells in the retroperitoneum because the tumor was not located in the adrenal gland or the Zuckerkandl organ, according to the CT findings. The immunohistochemical findings of this rare case of a composite PG and GN in the retroperitoneum are reported with a focus on the peculiar arrangement of these two components.

Composite paraganglioma-ganglioneuroma of the urinary bladder: a rare neoplasm causing hemodynamic crisis at tumour resection

A 64-year-old man presented with gross painless hematuria. Cystoscopy revealed a submucosal bladder neck mass covered by normal urothelium. During transurethral resection, the patient developed hemodynamic crisis including sinus bradycardia. Histopathologic examination revealed a primary bladder composite paraganglioma-ganglioneuroma (CPG). The patient underwent partial cystectomy and is symptom-free after one year. Bladder CPGs are extremely rare neoplasms that may result in life-threatening catecholamine secretion, especially during tumour manipulation. These tumours require complete surgical excision and should be included in the differential diagnosis of any solitary bladder mass covered by normal urothelium, especially when there is a history of hypertension or micturition attacks.

Composite paraganglioma-ganglioneuroma in the retroperitoneum

Background

Paragangliomas occur most commonly in head and neck region and much less frequently, they are found in the retroperitoneum. Composite paraganglioma-ganglioneuroma of the retroperitoneum is very rare.

Case presentation

We present an unusual case of retroperitoneal composite paraganglioma-ganglioneuroma discovered on computed tomography in a 63-year-old female patient. Routine hematological examination and biochemical tests were within normal limits. Plasma adrenaline was 0.042 ng/ml, plasma noradrenaline 0.341 ng/ml, and plasma dopamine <0.01 ng/ml. An abdominal contrast-enhanced CT scan and magnetic resonance imaging revealed a 6.5 cm heterogeneous retroperitoneal mass with a cystic component. The retroperitoneal tumor accumulated ¹³¹I-Metaiodobenzylguanidine (¹³¹I-MIBG) 48 hours after radioisotope injection. Under the diagnosis of paraganglioma in the retroperitoneum, the patient underwent surgery. The resected tumor (6.5 × 5 × 3 cm) was solid and easily removed en bloc. The cut surface of the tumor and histology revealed two different components in the tumor: paraganglioma centrally and ganglioneuroma on the periphery. She remains disease-free 18 months after surgery.

Conclusion

This case reminds us that neuroendocrine tumor should be included in the differential diagnosis of a retroperitoneal mass although composite paraganglioma-ganglioneuroma in the retroperitoneum is very rare.

Composite paraganglioma-ganglioneuroma of the urinary bladder

Presented herein is the case of a 73-year-old man, complaining of dysuria, who had a composite paraganglioma-ganglioneuroma of the urinary bladder (CPGUB). At cystoscopy a submucosal tumor was found in the urinary bladder and resected after transurethral biopsy. The levels of serum catecholamine and 24 h urinary excretion of catecholamine and vanillylmandelic acid were elevated. Grossly, the resected tumor, measuring 4 x 3 x 2.5 cm, had a brownish cut surface with no necrosis and hemorrhage. Histologically, the tumor had alternating cellular and fibrous areas. The cellular areas consisted of polygonal cells, arranged in well-defined nests (Zellballen) and positive for Grimelius staining, with abundant amphophilic to acidophilic cytoplasm, occasionally containing eosinophilic hyaline globules and brown pigments. Although the nuclei of several polygonal cells were bizarre, mitoses and vascular invasion were not found. Fibrous areas consisted of spindle cells, resembling Schwann cell, admixed with ganglionic cells. To the authors' knowledge, only four cases of CPGUB have been reported in the English-language literature. Detailed reported cases and the present case showed no malignant features, such as extra-bladder infiltration and metastasis, and no recurrence in the short length of follow up. Accumulation of long-term follow-up cases may provide valuable prognostic information on this composite tumor.