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Concept: Pheochromocytoma

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Takotsubo cardiomyopathy is seen, though rarely, in anaphylaxis treated with epinephrine. Stress cardiomyopathy is most likely to occur in middle-aged women. The underlying etiology is believed to be related to catecholamine release in periods of intense stress. Catecholamines administered exogenously, and those secreted by neuroendocrine tumors (e.g., pheochromocytoma) or during anaphylaxis have been reported to cause apical ballooning syndrome, or takotsubo syndrome. However, reverse takotsubo stress cardiomyopathy is rarely seen or reported in anaphylaxis treated with epinephrine.

Concepts: Cardiomyopathy, Neuroendocrine tumor, Epinephrine, Norepinephrine, Cardiovascular diseases, Pheochromocytoma, Catecholamine, Takotsubo cardiomyopathy

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Pheochromocytoma and/or paraganglioma associated with neurofibromatosis type 1, multiple endocrine neoplasia type 2A, and von Hippel-Lindau disease have different catecholamine biochemical phenotypes. We examined perioperative outcomes of pheochromocytoma/paraganglioma resection in 3 syndromic forms.

Concepts: Genetic disorders, Genodermatoses, Multiple endocrine neoplasia, Rare diseases, Von Hippel–Lindau disease, Von Hippel–Lindau tumor suppressor, Pheochromocytoma, Hereditary cancers

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(18)F-FDOPA illustrates the properties of uptake and storage of catecholamines in pheochromocytomas (PHEOs). Until now, the relationship between (18)F-FDOPA quantitative parameters and a PHEO secretory profile has not been specifically evaluated.

Concepts: Pheochromocytoma, Catecholamine

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Pheochromocytomas are catecholamine-secreting neoplasms, arising from adrenomedullary chromaffin cells. In type 2 multiple endocrine neoplasia (MEN2) syndrome, pheochromocytomas are usually benign but with predisposition to be bilateral (50%-80% of cases).The authors present the case of a young patient diagnosed with uncommonly large bilateral cystic pheochromocytomas and simultaneous detection of medullary thyroid carcinoma. Molecular testing confirmed germline RET codon C634 mutation, consistent with MEN2A syndrome. The patient underwent bilateral laparoscopic adrenalectomy plus total thyroidectomy with central lymph node dissection without associated complications. The histopathological study of the surgical specimens revealed bilateral benign pheochromocytomas (Ki67 of 2%) and a medullary carcinoma of the thyroid T1bN0M0; R0, respectively. One year after surgery, the patient was considered free of disease.This case demonstrates that bilateral laparoscopic adrenalectomy can be a safe and feasible approach for phechromocytomas in MEN2 syndrome, even in lesions with large diameter. However, due to elevated possibility of recurrence, patients should maintain lifelong follow-up.

Concepts: Cancer, Thyroid disease, Multiple endocrine neoplasia, RET proto-oncogene, Medullary thyroid cancer, Multiple endocrine neoplasia type 2, Pheochromocytoma, Thyroid neoplasm

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Over the last years, the knowledge of MEN2 and non MEN2 familial forms of pheochromocytoma (PHEO) has increased. In MEN2, PHEO is the second most frequent disease: the penetrance and age at diagnosis depend on the mutation of RET. Given the prevalence of bilateral PHEO (50% by age 50), adrenal sparing surgery, aimed at sparing a part of the adrenal cortex to avoid adrenal insufficiency, should be systematically considered in patients with bilateral PHEO. Non MEN2 familial forms of PHEO now include more than 20 genes: however, only small phenotypic series have been reported, suggesting that phenotypic features of isolated hereditary PHEO must be better explored, and follow-up series are needed to better understand the outcome of patients carrying mutations of these genes. The first part of this review will mainly focus on these points. In the second part, a focus will be given on MEN2 and non MEN2 familial forms of hyperparathyroidism (HPTH). Again, the management of MEN2 HPTH should be aimed at curing the disease while preserving an optimal quality of life by a tailored parathyroidectomy. The phenotypes and outcome of MEN1, MEN4 and HRPT2 related HPTH are briefly described, with a focus on the most recent literature data, and is compared with familial hypocalciuric hypercalcemia.

Concepts: Gene, Genetics, Natural selection, Evolution, Phenotype, Multiple endocrine neoplasia, Multiple endocrine neoplasia type 2, Pheochromocytoma

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Pheochromocytomas and paragangliomas (PPGLs) belong to the family of neural crest cell-derived neoplasms. In up to 70% of cases they are associated with germline and somatic mutations in 15 well-characterized PPGL driver or fusion genes. PPGLs can be grouped into three main clusters, where cluster 1 includes PPGLs characterized by a pseudohypoxic signature. Although cluster 1 tumors share several common features, they exhibit unique behaviors. We present here unique insights into the imaging phenotypes of cluster 1 PPGLs based on glucose uptake, catecholamine metabolism, and somatostatin receptor expression. Recent data suggest that succinate is a major player in the imaging phenotype of succinate dehydrogenase-deficient PPGLs. This review emphasizes the emerging stromal cell-succinate interaction and highlights new perspectives in PPGL theranostics.

Concepts: Protein, Gene, Genetics, Cancer, Mutation, Evolution, Phenotype, Pheochromocytoma

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Pheochromocytomas are rare endocrine tumors that can have a significant impact on a variety of organ systems, including the cardiovascular system. Although the pathophysiology is not completely understood, pheochromocytomas exert their effects through high levels of catecholamines, mainly epinephrine and norepinephrine, which stimulate adrenergic receptors, including those within the cardiovascular system. Although the most common cardiovascular manifestation is hypertension, patients with pheochromocytoma can present with arrhythmia, hypotension, shock, myocardial ischemia, cardiomyopathy, aortic dissection, and peripheral ischemia. The medical management of the cardiovascular effects of pheochromocytoma is via blockade of adrenergic receptors, usually through the use of alpha blockers, with the addition of beta blockers if needed. However, only surgical resection of the pheochromocytoma is potentially curative, and this tumor requires unique management perioperatively. Because of the variability of presentation and the significant morbidity and mortality of patients with an undiagnosed pheochromocytoma, this entity should not be overlooked in the evaluation of patients with a wide variety of cardiovascular disorders.

Concepts: Hypertension, Epinephrine, Vasoconstriction, Norepinephrine, Adrenergic receptor, Pheochromocytoma, Beta blocker, Catecholamine

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Catecholamines stimulate renin-secretion in the juxtaglomerular cells of the kidney and a number of case reports suggest an association between pheochromocytoma and activation of the RAAS. Therefore, it could be asked whether patients suffering from pheochromocytoma with high concentrations of circulating catecholamines present with oversecretion of renin and aldosterone. We identified twelve patients with excessive catecholamine secretion due to pheochromocytoma and compared them to a group of twelve patients with essential hypertension (EH) with regard to the activation of the renin-angiotensin-aldosterone-system (RAAS). The PubMed database was screened for studies that investigate the association between pheochromocytoma and activation of the RAAS. The plasma concentrations of metanephrines (19.9-fold) and normetanephrines (29.5-fold) were significantly higher in the pheochromocytoma group than in the EH group. Renin and aldosterone levels were 1.3-fold and 1.6-fold higher, respectively, as compared to the EH group, whereas the differences were not statistically significant. There was no significant correlation between plasma metanephrine or normetanephrine levels and the plasma renin concentration (rs=0.077, rs=0.049, respectively) in our patients. The data from our institution and from review of literature suggest that an association between pheochromocytoma in the context of high plasma catecholamine levels and activation of the RAAS is present. However, results have not been consistent. Thus, other causes of RAAS-activation should be considered also in the presence of pheochromocytoma or reinvestigation for aldosteronism should be offered to such patients after removal of the catecholamine-producing tumour.

Concepts: Kidney, Hypertension, Blood pressure, Aldosterone, Renin-angiotensin system, Renin, Pheochromocytoma, Catechol-O-methyl transferase

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Pheochromocytomas are rare neuroendocrine tumors that produce and store catecholamines. Without adequate preparation, the release of excessive amounts of catecholamines, especially during anesthetic induction or during surgical removal, can produce life-threatening cardiovascular complications. This review focuses on the perioperative management of pheochromocytoma/paragangliomas, initially summarizing the clinical aspects of the disease and then highlighting the current evidence available for preoperative, intraoperative, and postoperative anesthetic management.

Concepts: Medicine, Neuroendocrine tumor, Pheochromocytoma, Catecholamine

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To describe outcomes of patients with metyrosine (MET) pretreatment for abdominal surgical resection of pheochromocytoma or paraganglioma (PCC/PGL) compared with patients who had phenoxybenzamine (PBZ) pretreatment.

Concepts: Resection, Pheochromocytoma