Pheochromocytoma of the urinary bladder: a systematic review of the contemporary literature

Functional paraganglioma of the bladder: Both radiographic-negative and laboratory-negative case

INTRODUCTION

Paraganglioma has been determined to be an extra-adrenal pheochromocytoma. Paraganglioma of the bladder is a rare entity, accounting for 0.06% of all bladder tumors.

CASE PRESENTATION

A 58-year-old woman had been annually followed up since being diagnosed with rectal cancer 5 years ago. In January 2018, follow-up computed tomography detected a bladder tumor, and she was referred to our department for a further examination. Cystoscopy revealed a submucosal tumor on her right bladder wall. We performed transurethral resection of the bladder tumor. When we first marked the tumor margin, the systolic blood pressure increased, so we abandoned resection. We performed meta-iodobenzylguanidine scintigraphy and acid urinary collection, neither of which revealed any abnormal findings. We therefore performed open partial cystectomy based on a clinical diagnosis of paraganglioma of the bladder. The pathological findings revealed paraganglioma of the bladder.

CONCLUSION

We herein report a case of paraganglioma of the bladder.

Pheochromocytoma of the Urinary Bladder with Recurrence 10 Years Later

Pheochromocytoma of the bladder is a rare bladder tumor. We report a case of an 80-year-old female who presents with recurrent bladder tumors consistent with pheochromocytoma of the bladder, discovered 10 years post-resection of a prior pheochromocytoma of the urinary bladder. She was treated with partial cystectomy and was found to be symp tom free at 6-month follow-up.

The Hypertensive Headache: a Review

PURPOSE OF REVIEW

The purpose of this review is to provide an overview and update on the common causes of headache attributed to arterial hypertension with a focus on secondary headache disorders. We will also highlight uncommon and recent findings in this area of research.

RECENT FINDINGS

There is some controversy in the relationship between chronic hypertension and headache, particularly migraine; recent research suggests that there may be a link, but it is likely complex and multifactorial. Many recent studies and case reports demonstrate that the pathophysiology underlying the onset of headache as it relates to abrupt rises in blood pressure seems to lie at the cellular level and mechanically becomes an issue with disruption of the blood-brain barrier. Although not a formally defined headache entity, carotid revascularization syndrome demonstrates this phenomenon and also has a recent set of proposed criteria that include headache and elevated blood pressure. This paper reviews the various etiologies of hypertensive headaches, mostly in regard to headache as a secondary symptom of elevated blood pressure. We will also discuss trends of hypertensive headache in pregnancy. Finally, we will touch on controversy that exists in relation to chronic hypertension and its causal relationship to headache as well as the relationship between hypertension and migraine.

Imaging Characteristics of a Bladder Wall Paraganglioma

A 65-year-old man with a history of hypertension and nephrolithiasis presented with flank pain. Urographic CT demonstrated a 1.7-cm nodule arising from the bladder wall. The patient was referred for cystourethroscopy. During the procedure, the patient became hypertensive while under general anesthesia. No biopsy or resection was performed. To work up for possible bladder paraganglioma, a I-MIBG scan was ordered, and the patient was referred to endocrinology. On SPECT/CT images, the bladder nodule demonstrates marked uptake of MIBG radiotracer, confirming the diagnosis of a genitourinary paraganglioma arising from the bladder wall.

Clinicopathological characteristics and survival outcomes of bladder neuroendocrine carcinomas: a population-based study

Background

Bladder neuroendocrine carcinomas (BNECs) are relatively a rare type of tumor. The aim of this study was to examine the clinicopathological characteristics and predictors of survival outcomes of patients with BNECs based on the analysis of the national Surveillance, Epidemiology, and End Results (SEER) database.

Materials and methods

Kaplan-Meier analysis with log-rank test was used for survival comparisons. Multivariate Cox regression model was employed to analyze the effect of different treatments on overall survival (OS) and cancer-specific survival (CSS).

Results

A total of 910 patients were identified between 2004 and 2014. Overall, 648 (71.2%) patients had small cell neuroendocrine carcinoma (SCNEC), 35 (3.8%) had large cell neuroendocrine carcinoma (LCNEC), 10 (1.1%) had carcinoid tumor (well-differentiated neuroendocrine tumor), 16 (1.8%) had paraganglioma/pheochromocytoma (PGL/PHEO), 619 (68.0%) had a poorly differentiated or undifferentiated histology grade, 214 (23.5%) presented with metastatic disease, 586 (64.4%) underwent transurethral ablation/destruction for bladder tumor, and 245 (26.9%) had partial/total cystectomy. Cystectomy+chemotherapy+radiotherapy (CCR) has the highest long-term survival rate among various treatments. The 1-, 3-, and 5-years CSS of CCR were 56%, 56%, and 56%, respectively. By using multivariable Cox proportional hazard model, age, histology, N stage, SEER stage, tumor size, radiotherapy, chemotherapy, and local treatment of the primary site were identified as independent predictors for OS and CSS; all P<0.05.

Conclusion

In BNEC, SCNEC has an absolute advantage in number. SCNEC/LCNEC tend to be older men. PGL/PHEO and carcinoid tumors have younger mean ages, earlier tumor stages, and better prognosis than SCNEC/LCNEC. Surgery, radiotherapy and chemotherapy are better than conservative treatment. However, whatever cystectomy or bladder sparing, chemotherapy should be a major component of treatment.

Successful Resection of a Non-functional Paraganglioma with Celiac Trunk Invasion Followed by Common Hepatic Artery Reimplantation - A Case Report and Literature Review

Paragangliomas, as well as phaeochromocytomas, are vascular neuroendocrine lesions that might be encountered between neck and pelvis. In certain cases, a preoperative diagnosis is difficult to be established, so resection might be needed whenever a suspect mass is discovered at the imaging studies. Moreover, there are cases in which resection and reconstruction of an important vascular structure might be imposed. In this case report a 59-year-old patient was investigated for upper abdominal pain with postprandial features and was diagnosed with a retroperitoneal tumor of 4/6/7cm invading the celiac trunk. The tumor was successfully resected and the common hepatic artery was reinserted in the celiac stump.

Pathology and genetics of phaeochromocytoma and paraganglioma

Phaeochromocytoma and paraganglioma (PHEO/PGL) are rare tumours with an estimated annual incidence of 3 per million. Advances in molecular understanding have led to the recognition that at least 30-40% arise in the setting of hereditary disease. Germline mutations in the succinate dehydrogenase genes SDHA, SDHB, SDHC, SDHD and SDHAF2 are the most prevalent of the more than 19 hereditary genetic abnormalities which have been reported. It is therefore recommended that, depending on local resources and availability, at least some degree of genetic testing should be offered to all PHEO/PGL patients, including those with clinically sporadic disease. It is now accepted that that all PHEO/PGL have some metastatic potential; therefore, concepts of benign and malignant PHEO/PGL have no meaning and have been replaced by a risk stratification approach. Although there is broad acceptance that certain features, including high proliferative activity, invasive growth, increased cellularity, large tumour nests and comedonecrosis, are associated with an increased risk of metastasis, it remains difficult to predict the clinical behaviour of individual tumours and no single risk stratification scheme is endorsed or in widespread use. In this review, we provide an update on advances in the pathology and genetics of PHEO/PGL with an emphasis on the changes introduced in the WHO 2017 classification of endocrine neoplasia relevant to practising surgical pathologists.

A Rare Location and Presentation of Pheochromocytoma

Background: Pheochromocytomas typically are diagnosed in the adrenal gland and from the sympathetic nervous system. Bladder pheochromocytoma is a rare location for this tumor.

Case Presentation: We describe a 67-year-old Afro Caribbean woman referred to our hospital for an asymptomatic bladder tumor. Preliminary transurethral resection revealed bladder pheochromocytoma. After a comprehensive endocrine evaluation, we performed a robot-assisted laparoscopic partial cystectomy with ureteral reimplantation.

Conclusion: We present a rare case of bladder pheochromocytoma treated effectively with minimally invasive techniques. When confronted with a solid bladder mass, apart from the more common urothelial malignancies, a differential diagnosis of bladder pheochromocytoma should also be considered.

Successful Resection of a Non-functional Paraganglioma with Celiac Trunk Invasion Followed by Common Hepatic Artery Reimplantation - A Case Report and Literature Review

Paragangliomas, as well as phaeochromocytomas, are vascular neuroendocrine lesions that might be encountered between neck and pelvis. In certain cases, a preoperative diagnosis is difficult to be established, so resection might be needed whenever a suspect mass is discovered at the imaging studies. Moreover, there are cases in which resection and reconstruction of an important vascular structure might be imposed. In this case report a 59-year-old patient was investigated for upper abdominal pain with postprandial features and was diagnosed with a retroperitoneal tumor of 4/6/7cm invading the celiac trunk. The tumor was successfully resected and the common hepatic artery was reinserted in the celiac stump.

Postmicturition syndrome: a neglected syndrome dangerous for the bladder and the heart

Postmicturition syndrome refers to symptoms caused by overdistension of the bladder or micturition. Bladder paraganglioma is a rare neuroendocrine neoplasm, which arises from the chromaffin tissue of the sympathetic nervous system embedded in the muscle layer of the bladder wall. Clinical presentation of catecholamine-secreting paragangliomas may mimic that of hyperfunctioning adrenal pheochromocytoma. Typical symptoms such as sweating, palpitations, headache, nausea, hypertension, or flushing are due to catecholamine release and are related to micturition or bladder overdistension. We herein report the case of a 22-year-old woman admitted to the Emergency Department because of cranial trauma secondary to a car accident. She referred history of micturition-related headache, nausea, sweating, and increase in blood pressure since she was 13 years old. The neurological investigation was normal. No urogenital tract investigation was performed and, on admission, blood pressure was 190/125 mmHg. During hospitalization, abdominal ultrasonography, performed to rule out secondary hypertension, unexpectedly showed a large vascular soft tissue mass in the bladder wall, compatible with a paraganglioma. Twenty-four hours of urinalysis of catecholamines revealed high values of urine metanephrines. Abdominal magnetic resonance imaging and histopathological evaluation of the surgical specimen, following resection of the bladder lesion, confirmed the diagnosis. Our case underlines the importance not to underestimate symptoms compatible with postmicturition syndrome, especially in young patients, to make early diagnosis of bladder paraganglioma.

Management of bladder pheochromocytoma by transurethral resection

Bladder pheochromocytoma is the most common extra-adrenal genitourinary tumor. Endoscopic management is feared due to the risk of intra-operative hypertensive crisis. We described a case of successful endoscopic management of a bladder pheochromocytoma and discussed its technical aspects.

Malignant extra-adrenal pelvic paraganglioma in a paediatric patient

The extra-adrenal paraganglioma is a neoplasm originating in regional structures, uncommon in paediatrics. We report on a case of a 13-year-old patient who began with severe arterial hypertension, tachycardia, dilated cardiomyopathy and elevated levels of catecholamines in the blood and urine. The presence of a retrovesical pelvic mass in contact with the right vaginal dome was determined by imaging studies. A diagnosis of malignant extra-adrenal pelvic paraganglioma with lymph node metastases was reached through biopsy and the surgical resection of subsequent local recurrences. Paragangliomas are usually located in the paravertebral zones from the base of the skull to the retroperitoneum and are benign in 90% of cases. This kind of neoplasia is uncommon in paediatrics, especially those located in the pelvis. In cases of masses of a gynaecological origin, a differential diagnosis should be considered, and a histological and immunohistochemical study is essential in certifying the diagnosis.

Functioning metastatic paraganglioma of the urinary bladder in a 10-year-old child

Paragangliomas of the urinary bladder are very rare tumours representing less than 1% of bladder tumours. Preoperative diagnosis is essential to avoid perioperative complications related to catecholamine release. A high index of suspicion should be maintained when the classical symptoms of voiding-related paroxysms of headache, palpitation and dizziness are present. We present a rare case of malignant paraganglioma of the urinary bladder in a 10-year-old boy. The patient had the classic presentation. We review the radiological diagnostic tools and findings of this rare entity.

Paraganglioma of the bladder in a kidney transplant recipient: A case report

Renal transplantation has been associated with a significantly increased risk of developing cancer, including bladder neoplasia, with urothelial carcinoma being the most frequent type of bladder cancer. Bladder paraganglioma, also referred to as extra-adrenal pheochromocytoma, is a rare but severe condition that may cause a severe hypertensive crisis during handling and mobilization of the tumor. We herein present the case of a 67-year-old kidney transplant recipient with a bladder polyp consistent with paraganglioma of the bladder. During bladder polyp resection, the patient developed severe hypertension, which resolved with appropriate treatment. The histological analysis of the resected bladder polyp was consistent with extra-adrenal pheochromocytoma, or paraganglioma, and the patient finally underwent partial cystectomy, with no reported postoperative recurrence. To the best of our knowledge, this is the first report of a case of paraganglioma of the bladder in a kidney tranplant recipient. Total or partial bladder cystectomy is considered to be an effective treatment for this type of bladder tumor. Screening for mutations of the succinate dehydrogenase subunit B gene may also be recommended.

Paraganglioma of the Urinary Bladder: A Series of 22 Cases in a Single Center

OBJECTIVE

Paraganglioma of the urinary bladder (PUB) is rare in bladder cancer, and currently, a study examining large number of cases from a single center has not been reported. This study aimed to present the clinical features, treatments, pathological characteristics, and prognosis of PUB.

PATIENTS AND METHODS

From January 2006 to June 2016, 22 patients were pathologically diagnosed with PUB in our hospital. Their clinical records, operative notes, pathological reports, and follow-up records were retrospectively reviewed.

RESULTS

The incidence of PUB in patients with bladder cancer was 0.92%. The mean age at diagnosis was 49.8 ± 14.6 years (range, 16-76 years) and the male to female ratio was 1:1. Fourteen cases (63.6%) were functional. The common indicative symptoms included hematuria (36.4%), hypertension (31.8%), micturition syncope (27.3%), headache (18.2%), and palpitation (13.6%). All neoplasms were completely resected via transurethral resection of bladder tumor (TURBT), en bloc transurethral resection with thulium-yag laser, or partial cystectomy. Most PUB samples were positive for immunohistochemical (IHC) staining markers such as chromogranin A (CgA), Synaptophysin (Syn), CD56, and S-100 protein, while negative for IHC markers such as cytokeratins (CKs) and Melan A. According to pathological reports, 72.7% of PUB cases were at stage T2, 18.2% at T3, and 9.1% at T4. Two cases (9.1%) with metastasis were malignant. Two patients (9.1%) were lost during follow-up, and the remaining 20 patients were followed up for a period of 67.8 ± 38.5 months (range, 6-130 months). Among them, 16 patients (80%) recovered after the surgery, 1 patient (5%) died of natural causes. PUB recurred in 3 patients (15%), and 1 patient among them died of PUB.

CONCLUSION

Despite the rarity, PUB should be suspected in patients with unexplained symptoms such as micturition syncope, hematuria, hypertension, headache, or palpitation. Surgery and adjuvant therapies are effective treatments for PUB. Compared with open surgery, laparoscopic partial cystectomy and robot-assisted laparoscopic partial cystectomy are advantageous in the treatment of PUB. Long-term follow-up is recommended for patients with PUB.

Genitourinary paraganglioma: Demographic, pathologic, and clinical characteristics in the surveillance, epidemiology, and end results database (2000-2012)

BACKGROUND

Extra-adrenal paragangliomas (PGLs) are infrequent, benign, and neuroendocrine tumors arising from chromaffin cells of the autonomic nervous system. Most PGLs are sporadic, but up to 32% are associated with inherited syndromes such as neurofibromatosis type 1, von Hippel-Lindau disease, and familial PGL. Although most PGLs develop above the umbilicus, they have been reported in the genitourinary (GU) tract. Owing to the paucity of literature on the rates of GU PGL, the objective of our study is to describe the demographic, pathologic, and clinical characteristics of GU PGL, and compare them to non-GU sites of PGL using the surveillance, epidemiology, and end results (SEER) database.

METHODS

The SEER 18 database was used to identify all cases of PGL from 2000 to 2012. Demographic, pathologic, and clinical characteristics were described using chi-square and t-test for categorical and continuous variables, respectively. The Kaplan-Meier method was used to compare overall survival (OS) between GU and non-GU PGL. Statistical significance was defined as P<0.05. All analyses were performed using excel and SAS/Stat version 9.4.

RESULTS

A total of 299 cases of PGL were retrieved from SEER, and 20 (6.7%) of the total PGL arose from the GU tract. The mean age at diagnosis was higher in non-GU than GU PGL (50.4±17.2 vs. 40.8±15.6, P = 0.026). Furthermore, 75% of GU PGLs developed in the bladder, followed by the kidneys/renal pelvis, and spermatic cord (20%). Non-GU PGL developed most frequently within the endocrine system (43%). PGL, overall, was more common in men than in women, and it was more common in whites than all other races. Although 55.5% of GU PGLs were organ confined, only 22.2% of non-GU PGLs were localized at diagnosis. All cases of PGL were treated with surgery. There were 2 cause-specific deaths in the GU PGL groups between 2000 and 2012. The 5-year OS was 93.3% for GU PGL vs. 65.5% in non-GU PGL (P = 0.062).

CONCLUSIONS

GU PGL remains rare with low incidence (6.7% of all PGL cases) in the US population between 2000 and 2012. Bladder PGL represents just 5% of all PGL. Moreover, GU PGL had better OS compared to PGL developing outside of the GU tract although the P-value only approached statistical significance. The bladder represents the most common site of involvement, and surgery is the mainstay of treatment for GU PGL. Clearer prognostic factors, including tumor grade and stage, are needed to better elucidate PGL management in the future; thus, pooled studies from various institutions with detailed clinical information are needed to delineate these prognostic factors.

Atypical presentation of bladder pheochromocytoma

Bladder pheochromocytoma is a rare tumor. The typical manifestations are hematuria, hypertension, headache, sweating, and tachycardia provoked by micturition or overdistention of the bladder. We herein report a case of bladder pheochromocytoma in a 52-year-old woman who presented without micturition attacks. Her clinical course had a latent period of 10 years. A urinary bladder tumor was found incidentally on magnetic resonance imaging. Cystoscopy revealed a large submucosal tumor covered by congested urothelium with a broad base over the left lateral wall of the bladder. Transurethral resection was performed, and the final diagnosis was confirmed by pathological analysis. The patient remained recurrence free after 7-year follow-up.

Neuroendocrine Tumors of the Urinary Bladder According to the 2016 World Health Organization Classification: Molecular and Clinical Characteristics

Neuroendocrine neoplasms of the urinary bladder are a rare type of tumor that account for a small percentage of urinary bladder neoplasms. These tumors of the urinary bladder range from well-differentiated neuroendocrine neoplasms (carcinoids) to the more aggressive subtypes such as small cell carcinoma. Despite the rarity of the neuroendocrine tumors of the bladder, there has been substantial investigation into the underlying genomic, molecular, and the cellular alterations within this group of neoplasms. Accordingly, these findings are increasingly incorporated into the understanding of clinical aspects of these neoplasms. In this review, we provide an overview of recent literature related to the 2016 World Health Organization Classification of Neuroendocrine Tumors of the Urinary Bladder. Particular emphasis is placed on molecular alterations and recently described gene expression. The neuroendocrine tumors of the urinary bladder are subdivided into four subtypes. Similar to their pulmonary and other extrapulmonary site counterparts, these have different degrees of neuroendocrine differentiation and morphological features. The clinical aspects of four subtypes of neuroendocrine tumor are discussed with emphasis of the most recent developments in diagnosis, treatment, and prognosis. An understanding of molecular basis of neuroendocrine tumors will provide a base of knowledge for future investigations into this group of unusual bladder neoplasms.

An unusual case of asymptomatic non-urothelial bladder tumour

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Bladder paragangliomas are rare and account for less than 0.05% of all bladder tumours.

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They can present as incidental findings without any clinical symptoms.

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Due to the non-specific nature, they are often not part of the urologists differential diagnoses.

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Pre-operative suspicion and management are essential to reduce anaesthetic risk.

Introduction

Non-urothelial tumours are rare and account for less than 5% of all bladder tumours. Bladder paragangliomas also known as extra-adrenal pheochromocytomas are of the non-urothelial subgroup. We present an unusual case of asymptomatic bladder paraganglioma.

Case report

A 77 year old lady presented with acute abdominal pain was found to have an incidental enhancing nodule in the bladder. During cystoscopy and transurethral resection the patient experienced significant fluctuations in blood pressure that required anaesthetic adjustments. Review of histology confirmed a diagnosis of bladder paraganglioma.

Discussion

Most bladder paraganglioma cases present with sympathomimetic related symptoms and microscopic haematuria but our patient was asymptomatic which resulted in inadequate pre-operative optimisation and high anaesthetic risk. Majority of paragangliomas are benign but there is a 20-40% chance of malignancy. The management options will predominantly depend on whether disease is localised, regional, metastatic or recurrent in nature.

Conclusion

Due to the non-specific nature of disease, variability of presentations and rare incidence, bladder paragangliomas are often not part of the urologists’ differential diagnoses. In our opinion, establishing guidelines should assist to achieve a balance between anaesthetic risks, cystoscopy and follow up.

Urinary Bladder Paragangliomas: How Immunohistochemistry Can Assist to Identify Patients With SDHB Germline and Somatic Mutations

Urinary bladder paraganglioma (paraganglioma) is a rare tumor of chromaffin cells of the sympathetic system of the urinary bladder wall. We studied 14 cases of this entity and investigated the usefulness of SDHB protein staining by immunohistochemistry (IHC) as a diagnostic tool to identify patients with bladder paragangliomas that could be associated with SDHB gene mutations, as these patients have a more aggressive disease. Eleven tumors from these patients were stained by IHC. Six of 11 tumors were negative for SDHB staining by IHC with no cytoplasmic staining in tumor cells when compared with normal tissues. Five of these 6 negative cases were confirmed to be positive for germline SDHB mutations. One case showed negative staining and no germline SDHB mutation; however, further investigation of the tumor revealed a somatic SDHB gene deletion. The remaining 5 cases showed strong cytoplasmic staining, but they were negative for the presence of SDHB mutation. They were found to be either sporadic tumors or part of von Hippel-Lindau syndrome. Staining for SDHA was positive in all cases. Our study confirms that there is very good correlation between the presence of an SDHB mutation, whether germline or sporadic, and negative SDHB IHC staining in urinary bladder paragangliomas, and this is the first study to demonstrate that somatic mutations can be recognized by IHC staining.

[Mesenchymal tumors of the urinary bladder]

Mesenchymal tumors and tumor-like lesions of the urinary bladder are rare. They encompass a heterogeneous group of reactive pseudosarcomatous tumor-like changes and benign neoplastic lesions as well as malignant neoplasms (sarcomas) with variable biological behavior. The well-known differential diagnostic difficulties related to these conditions are mainly due to their rarity and thus limited experience and familiarity with their histological features and due to the significant morphological overlap between fully benign reactive conditions and aggressive malignant neoplasms. The distinction between them may on occasion represent a real challenge and is associated with several pitfalls. This overview summarizes the clinicopathological and differential diagnostic aspects of the most important lesions and discuss their differential diagnosis in the light of current knowledge.

Pheochromocytoma multisystem crisis treated with emergency surgery: a case report and literature review

Background

Pheochromocytoma is a neuroendocrine tumor that predominantly presents with hypertension, palpitations, and tachycardia due to excessive catecholamine excretion. Although pheochromocytoma multisystem crisis (PMC) is relatively rare, urologists and clinicians should focus on early diagnosis as delay in initiating the appropriate treatment can lead to mortality

Case presentation

A 70-year-old man developed ileus after a few days of medication for hypertension. Computed tomography incidentally revealed a left adrenal mass. This finding together with his clinical course was compatible with pheochromocytoma. An α-blocker was administered immediately, and his blood pressure was well controlled. However, his general condition and laboratory data deteriorated rapidly, and the patient was diagnosed with PMC with lethal status. Thus, emergency adrenalectomy was performed without confirmation of catecholamine levels. From the resected specimen, his tumor was judged as pheochromocytoma. On immunohistochemical analysis, the proliferation index evaluated by Ki-67 staining was 9.7 %. This case report was approved by the Human Ethics Review Committee of the Nagasaki University Hospital.

Conclusion

The present case of PMC was successfully treated with emergency surgery. The benign pheochromocytoma also presented with high cell proliferation potential, which may be a cause of the extreme aggressiveness of PMC.

Incidental Diagnosis of Nonfunctional Bladder Paraganglioma

Nonfunctional bladder paragangliomas may present clinical, radiology and pathological features similar to bladder cancer, so knowledge of this generally benign neuroendocrine neoplasm is of great importance to avoid misdiagnosis. We present the case of a patient with no clinical symptoms of paraganglioma and with radiological and cystoscopy examination results suggestive of urothelial carcinoma but with pathological diagnosis of paraganglioma.

15 YEARS OF PARAGANGLIOMA: Clinical manifestations of paraganglioma syndromes types 1-5

The paraganglioma (PGL) syndromes types 1-5 are autosomal dominant disorders characterized by familial predisposition to PGLs, phaeochromocytomas (PCs), renal cell cancers, gastrointestinal stromal tumours and, rarely, pituitary adenomas. Each syndrome is associated with mutation in a gene encoding a particular subunit (or assembly factor) of succinate dehydrogenase (SDHx). The clinical manifestations of these syndromes are protean: patients may present with features of catecholamine excess (including the classic triad of headache, sweating and palpitations), or with symptoms from local tumour mass, or increasingly as an incidental finding on imaging performed for some other purpose. As genetic testing for these syndromes becomes more widespread, presymptomatic diagnosis is also possible, although penetrance of disease in these syndromes is highly variable and tumour development does not clearly follow a predetermined pattern. PGL1 syndrome (SDHD) and PGL2 syndrome (SDHAF2) are notable for high frequency of multifocal tumour development and for parent-of-origin inheritance: disease is almost only ever manifest in subjects inheriting the defective allele from their father. PGL4 syndrome (SDHB) is notable for an increased risk of malignant PGL or PC. PGL3 syndrome (SDHC) and PGL5 syndrome (SDHA) are less common and appear to be associated with lower penetrance of tumour development. Although these syndromes are all associated with SDH deficiency, few genotype-phenotype relationships have yet been established, and indeed it is remarkable that such divergent phenotypes can arise from disruption of a common molecular pathway. This article reviews the clinical presentations of these syndromes, including their component tumours and underlying genetic basis.

Bladder paraganglioma with renal agenesis: A possible new association and its implications in the light of REarranged in transfection gene genetics

Pheochromocytoma/paraganglioma and renal agenesis are commonly reported conditions. Their coexistence, however, is rare, with few cases reported. We report the case of a 21-year-old male who presented with painless hematuria. He was found to have congenital absent right kidney along with bladder mass on imaging. Examination including blood pressure was normal. He underwent cystoscopy that showed a solid looking tumor on the anterior wall. Paraganglioma was suspected due to intraoperative rise in blood pressure during resection and was confirmed on histopathology. Subsequently after work up and preoperative alpha blockade, patient underwent partial cystectomy and excision of the paravesical mass. Histopathology showed paraganglioma confined to bladder wall with surgical margins free and a paravesical mass that was seminal vesicle cyst. On follow-up, patient is normotensive and asymptomatic. This coexistence of paraganglioma and renal agenesis may have a common genetic mechanism in the form of REarranged in Transfection (RET) gene mutation. This is a well-characterized gene, mutations of which are known to be associated with both conditions. Current knowledge of the role of RET gene in both conditions is reviewed to put forth RET mutation as the possible common underlying genetic mechanism along with possible clinical implications of the combination.

Association of urinary bladder paragangliomas with germline mutations in the SDHB and VHL genes

OBJECTIVE

Our primary goal was to examine the clinical characteristics of a series of patients with urinary bladder paragangliomas (UBPGLs), focusing particularly on their genetic backgrounds.

MATERIALS AND METHODS

We analyzed the medical records of patients who presented to the National Institutes of Health with UBPGL from 2000 to 2013 to determine their clinical characteristics and outcomes, biochemical phenotype, tumor size, and genetic background.

RESULTS

Of the 27 patients with UBPGLs who were identified, 17 (63%) had underlying genetic mutations. Overall, 14 (51.9%) patients had a germline mutation in the succinate dehydrogenase subunit B gene (SDHB), and 3 (11.1%) had mutations in the von Hippel-Lindau gene (VHL). Of the 21 patients who had biochemical data available before their first operation, 19 (90.5%) presented with a noradrenergic biochemical phenotype; 7 (33.3%) patients had tumors that also secreted dopamine. In addition, 1 patient (4.8%) had elevated metanephrine levels, and 2 (9.5%) had normal biochemical data. In total, 13 (48.1%) patients in the series were diagnosed with metastatic disease, at either first presentation or follow-up; 6 of these patients (46.1%) had SDHB mutations.

CONCLUSIONS

UBPGLs typically present with a noradrenergic phenotype and are frequently associated with underlying germline mutations. Patients presenting with these rare neuroendocrine tumors should be screened for these mutations. In addition, patients with UBPGLs should be followed up closely for metastatic development regardless of genetic background, as almost half of the patients in this series presented with metastatic disease and less than half of them had SDHB mutations.

Paraganglioma of the urinary bladder

Extra-adrenal paragangliomas of the urinary bladder are rare. Typically, patients present with symptoms related to catecholamine hypersecretion or mass effect, but these tumors can also be encountered incidentally on imaging studies obtained for a different purpose. It is important to recognize the key imaging features of this entity so that it may be suggested as a possible differential diagnosis in the setting of a newly identified bladder mass.