Genetic Alterations and Clinical Features in Brazilian Patients With Pheochromocytomas and Paragangliomas

Pheochromocytomas and paragangliomas are tumors derived from chromaffin cells which result from mutations of at least six different genes as autosomal dominant disorders. We evaluated the existence of correlations between genetic alterations and clinical data in 16 patients with pheochromocytomas and/or paragangliomas. From 2007 to 2019, 13 patients with pheochromocytoma [3 men, medium age 39 years (14–61)] and 3 with paraganglioma [1 men, medium age 33 years (22–35)] were evaluated regarding the presence of genetic mutations and possible correlations between the latter and some clinical features. Besides the mutations, tumor size, symptoms and signs present by the time of the diagnosis were studied. Four patients had pathogenic mutations (SDHB deletion encompassing the promoter and exon 1, C98Y in the SDHB gene, N78S in the VHL gene, and C634R in the RET gene) and one subject had a V90M variant in the TMEM127 gene. Two patients did not present mutations and nine had nonpathogenic mutations. Regarding the presence of clinical features before treatment, there was a predominance of arterial hypertension (75.0%), while the prevalence of tachycardia, abdominal pain and headaches was respectively 12.5%, 12.5% and 6.25%. There was no significant difference between the age of patients with pathogenic mutations and that of the other patients (31.2 vs. 38.6 years, p= 0.3952). Moreover, there were no differences regarding the prevalence of pheochromocytoma (p= 0.2143) or clinical features (p: hypertension= 0.6346, tachycardia= 0.4583, abdominal pain= 0.5417, headaches= 0.6875), or tumor dimensions (p= 0.4578) when the two groups were compared. However, the prevalence of paragangliomas was higher in patients with pathogenic mutations (p= 0.0179). In patients with pheochromocytoma and paraganglioma, the absence of correlations between pathogenic mutations and clinical features increases the importance of the genetic studies in the determination of treatment and prognosis of these tumors. Furthermore, subjects with germline mutations associated with pheochromocytoma and paraganglioma should undergo lifelong clinical, biochemical and imaging surveillance and their families should receive genetic counseling.

Transaminitis Evaluation Leads to the Incidental Diagnosis of Familial Paraganglioma Due to SDHB Mutation

Background: Paragangliomas are rare neuroendocrine tumors. Patients with succinate dehydrogenase subunit B (SDHB) gene mutations are predisposed to developing paraganglioma/pheochromocytoma. We are presenting the case of an incidental finding of a paraganglioma during an evaluation for transaminitis. Clinical Case: A 23-year-old male with a medical history of right hydrocele repair as a teenager was evaluated with an ultrasound of the abdomen for elevated liver enzymes and right upper quadrant discomfort. The ultrasound revealed a large lobular solid vascular 13.8 x 8.1 x 11.3 cm mass in the mid abdomen. He underwent a CT of the chest, abdomen and pelvis which demonstrated a large retroperitoneal mass measuring 16 x 10 x 13.7 cm within the right mid abdomen. The mass was described as a large centrally necrotic peripherally enhancing right retroperitoneal mass displacing the IVC anteriorly. The patient subsequently underwent an image-guided biopsy of the mass and the pathology revealed it was a paraganglioma. The patient denied any history of hypertension, orthostasis, headaches or palpitations. Biochemical workup for plasma catecholamines, plasma metanephrines, 24-hour urine catecholamines and metanephrines and cortisol were unremarkable. His transaminitis also resolved. He underwent a retroperitoneal paraganglioma excision and the final pathology was consistent with paraganglioma and negative for capsular invasion. He was referred to a genetic counsellor for testing since paragangliomas can be inherited. He also mentioned a family history of breast cancer in his mother and HTN and prostate cancer in his father. His test revealed that he had a c.289A>T mutation in his SDHB gene. He was encouraged to share the information with his family to help them understand the implications of his genetic test result. He underwent a surveillance PET scan which showed multiple osseous lesions in his temporal calvarium, sphenoid, spine and sacrum suggestive of metastasis. Repeat imaging with a DOTATATE PET scan showed stable disease. His transaminitis was transient, and we did not find a correlation to his paraganglioma. His imaging tests showed no liver metastasis. A CT of the head showed no evidence of intracranial metastasis. The current plan is to continue surveillance. His older brother underwent a genetic testing. He tested positive for the same SDHB mutation and underwent biochemical and imaging tests which were unremarkable. He too will continue surveillance. Conclusions: Patients with a succinate dehydrogenase subunit B (SDHB) gene mutations are predisposed to developing paraganglioma/pheochromocytoma. The tumors produce catecholamines, but can be biochemically silent as in our patient. They are inherited in an autosomal dominant manner. Our case highlights the importance for genetic counseling which increases the chances of early screening and surveillance in affected family members for optimal multidisciplinary management of patients.

Urinary bladder paraganglioma metastatic to the lung in a patient with SDHB gene mutation: A case report

Introduction: Paragangliomas are tumors originating from the neural crest. Most of them are benign and arise from various locations in the body. Extra-adrenal paragangliomas arise as sporadic cases in most settings or as part of heredofamilial syndromes in about one-quarter of cases. Succinate dehydrogenase subunit B (SDHB) gene mutations are associated with an aggressive clinical disease course of pheochromocytoma/paraganglioma.Methods: We present a 41-year-old male former smoker with a history of a growing right upper lung nodule on chest imaging. He had no cough or respiratory symptoms. Twenty-seven months prior, the patient underwent a cystoprostatectomy due to paraganglioma of the bladder. Genetic testing identified a pathogenic mutation in SDHB gene, c.166_170delCCTCA (p.Pro56Tyrfs*5). He underwent a wedge resection of the lung nodule.Results: Sectioning of the lung wedge revealed a well-circumscribed, firm tan nodule. Microscopically there were nests of large neoplastic cells with round nuclei and eosinophilic granular cytoplasm. Tumor cells were positive for synaptophysin and chromogranin and negative for pan-cytokeratin. S-100 protein highlighted sustentacular cells. Morphologically, the pulmonary neoplasm was similar to the primary tumor of the bladder. These features are consistent with a bladder paraganglioma metastatic to the lung, in a background of a hereditary paraganglioma syndrome.Conclusion: Extra-adrenal paraganglioma occurring in a setting of hereditary paraganglioma syndrome has a high risk of metastasis. Lifelong surveillance even after prompt resection of the primary tumor with negative margins is required to ensure early detection of metastasis and prevent complications associated with it.

SDH-deficient renal cell carcinoma: A case report associated with a novel germline mutation

Routine examination of an asymptomatic 40-year-old female patient revealed a right unilateral and unifocal renal mass. The patient underwent a partial nephrectomy, and the renal specimen was sent for histopathologic examination. Molecular testing revealed a heterozygous variant NM_003000.3:c.412G>T, p.(Asp138Tyr), in SDHB gene.

Cardiac paraganglioma with sulfur subunit B gene mutation: a case report

Background Pheochromocytoma and paraganglioma is a rare disease with a prevalence of 0.2–0.6% in hypertensive patients from outpatient. Case summary A 21-year-old man complained of blood pressure elevation over one year and persistent hyperhidrosis near 5 years. In local hospital, a mass in the pericardial space with abundant blood flow was observed via echocardiography and confirmed under minimally invasive thoracotomy. With suspicion of malignant cardiac mass, the patient was recommended to transfer for further diagnosis and treatment. Combining evaluation for blood and urinary catecholamine levels, somatostatin receptor imaging, and iodine-131 metaiodobenzylguanidine scintigraphy, he was confirmed with the diagnosis of cardiac paraganglioma with blood supply from the right coronary artery identified via angiography. The cardiac tumour was then surgically resected and confirmed with a pathological diagnosis of paraganglioma. Subsequent genetic test suggested succinate dehydrogenase complex iron sulfur subunit B (SDHB) gene mutation. At 5-month follow-up, the patient was recovered with normal levels of blood catecholamines and catecholamine metabolites. Discussion Cardiac paraganglioma should be considered and evaluated in hypertensive patients with cardiac mass, even in non-typical population. Given a potential risk of developing malignancies, close follow-up is significant in patients with SDHB gene mutations.

Large Retroperitoneal Paraganglioma Associated with Germline Mutation of the Succinate Dehydrogenase Gene

Paragangliomas (PGLs) are rare neural tumors that can be benign or malignant and often associated with familial syndromes. We present a case of a 23-year-old male with a large retroperitoneal PGL found incidentally during the workup of elevated liver enzymes. After surgical excision, the patient was found to have an autosomal dominant mutation in the succinate dehydrogenase B (SDHB) gene, which when compared to sporadic PGLs or other familial syndromes is associated with a higher risk of tumor recurrence, occult metastasis, and development of other cancers. The patient’s first-degree relatives were recommended to undergo screening for the genetic mutation.

Paraganglioma of the Urinary Bladder Metastatic to the Lung in a Patient with SDHB Gene Mutation: A Case Report

Introduction/Objective Paragangliomas are tumors originating from the neural crest. Most tumors are benign and arise from various locations in the body. Extra-adrenal paragangliomas arise as sporadic cases in most settings or as part of heredofamilial syndromes in about one-quarter of cases. Succinate dehydrogenase subunit B (SDHB) gene mutations are associated with an aggressive clinical disease course of pheochromocytoma/paraganglioma. Methods We present a 41-year-old male former smoker with a history of a growing right upper lung nodule on chest imaging. He had no cough or respiratory symptoms. Twenty-seven months prior the patient underwent a cystoprostatectomy due to paraganglioma of the bladder. Genetic testing identified a pathogenic mutation in SDHB gene, c.166_170delCCTCA (p.Pro56Tyrfs*5). He underwent a wedge resection of the lung nodule. Results Sectioning of the lung wedge revealed a well circumscribed, firm tan nodule. Microscopically there were nests of large neoplastic cells with round nuclei and eosinophilic granular cytoplasm. Tumor cells were positive for synaptophysin and chromogranin and negative for pan-cytokeratin. S100 highlighted sustentacular cells. The pulmonary neoplasm was morphologically similar to the prior tumor of the bladder. These features are consistent with a metastatic urothelial paraganglioma to the lung, in a background of a hereditary paraganglioma syndrome. Conclusion Extra-adrenal paraganglioma occurring in a setting of hereditary paraganglioma syndrome has a higher risk of metastasis. Lifelong surveillance even after prompt resection of primary tumor with negative margins is required to ensure early detection of metastasis and prevention of complications associated with it.