Pheochromocytoma - update on disease management

An Unusual Case of Pheochromocytoma Associated with von Hippel-Lindau Disease and Lynch Syndrome During Pregnancy

Pheochromocytomas (PCCs) and/or paragangliomas (PGLs) are a challenge to diagnose during pregnancy because of elusive signs and testing difficulties. We report a 25-year-old woman with no pertinent medical history who presented to the hospital with hypertension, vision loss, and weakness and was initially diagnosed with preeclampsia. Imaging showed hemangioblastomas in the medulla and thoracic spine, pancreatic cysts, and a renal cyst. The endocrinology service was consulted for possible PCCs associated with von Hippel-Lindau disease (VHL). Serum and urine normetanephrine levels were elevated despite the lack of overt PCCs/PGLs seen on magnetic resonance imaging and magnetic resonance angiography. The patient was medically managed with doxazosin and then labetalol. Despite successful resection of the hemangioblastoma in the medulla, the patient suffered respiratory distress requiring tracheostomy and venous-venous extracorporeal membrane oxygenation (V-V ECMO) and fetal demise. After 3 months, the patient was discharged to rehabilitation. Follow-up genetics were heterozygous for VHL and Lynch syndrome. DOTATATE positron emission tomography/computed tomography scan showed a small hepatic focus of a maximum standard uptake value of 12.1. Altogether, this case illustrates the importance of prompt diagnosis and proper management of PCCs/PGLs during pregnancy and incorporating genetic information during surveillance to lower morbidity and mortality.

Sulfasalazine as a cause of false-positive elevation of urinary normetanephrine in patients with adrenal mass and suspected phaeochromocytoma: a diagnostic challenge

In patients with suspected phaeochromocytoma, biochemical screening of urine or blood for excess secretion catecholamines and/or their metabolites is performed. Elevated levels of catecholamines and metanephrines help in establishing the diagnosis of phaeochromocytoma. In two patients with adrenal lesions who were subjected to biochemical testing significantly elevated urinary normetanephrines appeared to establish the diagnosis of phaeochromocytoma. However, on subsequent investigations, this was demonstrated to be a 'false positive' finding. Both these patients were on sulfasalazine, an anti-inflammatory drug used in inflammatory bowel disease, rheumatoid arthritis and ankylosing spondylitis. Sulfasalazine can cause analytical interference in some assays for urinary normetanephrine and result in spuriously elevated levels, leading to misdiagnosis of phaeochromocytoma. In this report, one patient underwent adrenalectomy and another had conservative management.Although this has been previously reported, increased awareness of the possibility of false-positive results on urinary metanephrines testing is important to reduce the potential for misdiagnosis and unnecessary treatment.

Pediatric total fractionated metanephrines: age-related reference intervals in spot urine

BACKGROUND

Sparse metanephrines reference intervals in pediatric populations are available and different study designs and technologies/ assays used in these studies lead to hardly transferable data from a laboratory to another. The aim of this study was to update pediatric reference intervals of total fractionated metanephrines in spot urine samples, using a commercial extraction kit run on a specific high-pressure liquid chromatograph coupled with an electrochemical detector.

METHODS

Four hundred and fifty-two spot pediatric urinary samples previously submitted to urinalysis were consecutively included in the study with the exclusion of children's samples with diagnosis or clinical suspicion of paraganglioma/pheochromocytoma, kidney diseases and arterial hypertension. Urinary metanephrine, normetanephrine and 3-methoxytyramine were extracted with ClinRep^® HPLC Complete kit and run on HPLC Prominence liquid chromatograph LC-20AT (Shimadzu Italia S.r.l. Milan, Italy) coupled with Decade II electrochemical detector (Antec Scientific, Zoeterwoude, the Nederlands, provided by Alfatech S.r.l., Genoa, Italy). Results were expressed as the ratio analyte-to-creatinine.

RESULTS

Any of the three analytes required a repartition by gender (metanephrine P=0.27; normetanephrine P=0.90 and 3-methoxytyramine P=0.18). A significant statistically inversely proportional relation with age was found for metanephrine (P<0.0001; ρ=-0.72), normetanephrine (P<0.0001; ρ=-0.75) and 3-methoxytyramine (P<0.0001; ρ=-0.83). Reference intervals were calculated as function of age.

CONCLUSIONS

This study provides pediatric reference intervals for urinary fractionated total metanephrines in spot urine calibrated on a specific instrumentation and extraction commercial kit.

Outcome of Partial Adrenalectomy in MEN2 Syndrome: Personal Experience and Systematic Review of Literature

Background: Partial adrenalectomy (PA) is an alternative option to total adrenalectomy for the treatment of hereditary pheochromocytoma (PHEO) to preserve cortical function and avoid life-long steroid replacement. The aim of this review is to summarize current evidence in terms of clinical outcome, recurrence, and corticosteroid therapy implementation after PA for MEN2-PHEOs. Material and Methods: From a total of 931 adrenalectomies (1997-2022), 16 of the 194 patients who underwent surgical treatment of PHEO had MEN2 syndrome. There were six patients scheduled for PA. MEDLINE^®, EMBASE^®, Web of Science, and Cochrane Library were searched for English studies from 1981 to 2022. Results: Among six patients who underwent PA for MEN2-related PHEO in our center, we reported two with bilateral synchronous disease and three with metachronous PHEOs. One recurrence was registered. Less than 20 mg/day Hydrocortison therapy was necessary in 50% of patients after bilateral procedures. Systematic review identified 83 PA for MEN2-PHEO. Bilateral synchronous PHEO, metachronous PHEO and disease recurrence were reported in 42%, 26%, and 4% of patients, respectively. Postoperative steroid implementation was necessary in 65% of patients who underwent bilateral procedures. Conclusions: PA seems to be a safe and valuable option for the treatment of MEN2-related PHEOs, balancing the risk of disease recurrence with the need for corticosteroid therapy.

Pheochromocytoma with an unusual presentation

Pheochromocytoma, is a rare neuroendocrine tumor, which usually presents as hypertension. We report a young male patient, who presented with intracerebral hemorrhage and intractable hypertension. On further evaluation, for uncontrolled secondary hypertension, he was diagnosed to have right adrenal pheochromocytoma. After hemodynamic stabilization, laparoscopic adrenelectomy was performed. Pheochromocytoma crisis presenting as intracerebral hemorrhage and cardiomyopathy is an uncommon phenomena. Even though it is a crisis, it is not a surgical emergency. Proper preoperative hemodynamic stabilization is essential before surgery is performed. An experienced anesthetist, to manage intraoperative fallacies, is warranted. Postoperatively, they must be on lifelong follow-up to watch for recurrence.

Elemental Composition of Pheochromocytoma Resolved on Solid/Adrenal Tissue and Whole Blood Level

Pheochromocytoma (PCC) is an unusual benign adrenal tumor with an unexamined status of the elements. This study delivers the first insight into the levels of microelements (Mn, Co, Cu, Zn, As, Se, Th), toxic elements (Cd, Pb, U), and macroelements (Na, K, Mg, Ca) in both adrenal tissue and whole blood samples collected from PCC patients. The results were strengthened by comparing recorded findings with the patients' healthy adrenal tissue (HAT) and with whole blood samples from the healthy individuals. PCCs had significantly higher levels of Zn, Se, Na, K, and Mg and lower levels of Mn, Co, Pb, and As than that of HATs. Compared to healthy blood samples, the patients' blood exhibited considerably higher levels of Na, K, and Ca but significantly lower levels of Mn, Cu, Zn, Se, and Mg. Females had significantly higher levels of essential Se and toxic Pb and Cd in their PCC tissue samples compared to males. PCC tissue levels of Mn and Cu were significantly elevated in smokers over levels in nonsmokers and in PCC patients with tumor sizes below 5 cm compared to PCC diameters above 5 cm. The data presented in this study provide a new insight into the pathophysiology of PCC. Thus, recorded elements should be considered as initiators/modifiers of PCC and potential inductors of malignant transformation. The findings of this research deepen scientific understanding of this rare adrenal disease, which, in turn, could highlight the pathogenesis of PCC.

Paraganglioma in pregnancy: A case series and literature review

Paragangliomas are rare neuroendocrine neoplasms which are often catecholamine-secreting and associated with familial syndromes. Described here are three women with a variety of pathology: isolated secretory paraganglioma diagnosed in pregnancy, secretory metastatic paraganglioma in pregnancy and non-secretory metastatic paraganglioma in pregnancy. Whilst paragangliomas are associated with morbidity and mortality during pregnancy, good maternal and fetal outcomes can be achieved through individualised care within the context of a multidisciplinary team. Although paragangliomas are associated with morbidity and mortality in pregnancy, good maternal and fetal outcomes can be achieved through individualised care within the context of a multidisciplinary team.

Extra-adrenal phaeochromocytoma in a resource poor setting: A case report

Phaeochromocytomas are catecholamine-secreting tumors arising in the chromaffin cells of the adrenal medulla. They are a rare cause of secondary hypertension. However, catecholamine secreting tumors may also be found in the extra-adrenal sites, producing similar symptoms as the adrenal phaeochromocytoma. The extra-adrenal phaeochromocytomas, are referred to as paragangliomas (PGLs). About 75% of extra-adrenal phaeochromocytomas are intra-abdominal, mostly located in perinephric, periaortic, and bladder regions. Most phaeochromocytomas secrete excessive amount of epinephrine and norepinephrine, whereas most paragangliomas secrete only norepinephrine. The excessive secretion of these products could lead to paroxysms of symptoms that could be life threatening. Medical management is initially offered, but definitive treatment involves surgical removal of the tumor, which requires promptness on the both the clinician and the patient sides. We present a case of an extra-adrenal phaeochromocytoma in an adult male with revealing imaging of a mass surrounding the bladder. The patient was managed with both alpha- and beta-adrenergic blockers. He declined the surgery and eventually died after appearing in an acute hypertensive crisis.

Multiple endocrine neoplasia 1: a broad overview

This review article discusses the diagnoses and treatment of patients with multiple endocrine neoplasia type 1 (MEN 1). The most common tumors associated with MEN 1 are located in the pancreas, pituitary, and parathyroid glands. Less common tumors include neuroendocrine tumors of the lung and thymus, adrenal tumors, and cutaneous lesions. This article describes the diagnosis, clinical manifestations, treatment, and surveillance of tumors associated with patients who are diagnosed with MEN 1.

Treatment-resistant hypertension in a post-transplant patient with cystic fibrosis: a rare case of phaeochromocytoma

SUMMARY

Phaeochromocytoma is a rare catecholamine-producing tumour. We present the case of phaeochromocytoma in a young man with a background history of a double-lung transplant for cystic fibrosis (CF). Clinical case: A 25-year-old man, with a background history of CF, CF-related diabetes (CFRD) and a double-lung transplant in 2012 was presented to the emergency department with crampy abdominal pain, nausea and vomiting. He was diagnosed with distal intestinal obstructions syndrome (DIOS). Contrast-enhanced CT imaging of the abdomen and pelvis showed a 3.4 cm right adrenal lesion. This was confirmed by a subsequent MRI of adrenal glands that demonstrated moderate FDG uptake, suggestive of a diagnosis of phaeochromocytoma. The patient was noted to be hypertensive with a blood pressure averaging 170/90 mm/Hg despite treatment with three different anti-hypertensive medications - amlodipine, telmisartan and doxazosin. He had hypertension for the last 3 years and had noted increasingly frequent sweating episodes recently, without palpitations or headache. Laboratory analysis showed elevated plasma normetanephrines (NMN) of 3167 pmol/L (182-867) as well as elevated metanephrines (MN) of 793 pmol/L (61-377) and a high 3-MT of 257 pmol/L (<185). Once cathecholamine excess was identified biochemically, we proceeded to functional imaging to further investigate. MIBG scan showed a mild increase in the uptake of tracer to the right adrenal gland compared to the left. The case was discussed at a multidisciplinary (MDT) meeting at which the diagnosis of phaeochromocytoma was made. Following a challenging period of 4 weeks to control the patient's blood pressure with an alpha-blocker and beta-blocker, the patient had an elective right adrenalectomy, with normalisation of his blood pressure post-surgery. The histopathology of the excised adrenal gland was consistent with a 3 cm phaeochromocytoma with no adverse features associated with malignant potential.

LEARNING POINTS

Five to ten per cent of patients have a secondary cause for hypertension. Phaeochromocytomas are rare tumours, originating in chromaffin cells and they represent 0.1-1.0% of all secondary hypertension cases. Secondary causes should be investigated in cases where: Patient is presenting <20 years of age or >50 years of age, There is refractory hypertension, or There is serious end-organ damage present. Patients may present with the triad of headache, sweating and palpitations or more vague, non-specific symptoms. Patients with suspected phaeochromocytoma should have 24-h urinary catecholamines measured and if available, plasma metanephrines measured. Those with abnormal biochemical tests should be further investigated with imaging to locate the tumour. Medical treatment involves alpha- and beta-blockade for at least 2 to 3 weeks before surgery as well as rehydration. There is a possibility of relapse so high-risk patients require life-long follow-up.

Postpartum Hypertension

PURPOSE OF REVIEW

Hypertension affects approximately 10% of pregnancies and may persist in the postpartum period. Furthermore, de novo hypertension may present after delivery, but its exact prevalence is not verified. Both types of hypertension expose the mother to eventually severe complications like eclampsia, stroke, pulmonary edema, and HELLP (hemolysis, elevated liver enzymes, low platelet) syndrome.

RECENT FINDINGS

Until today, there are limited data regarding the risk factors, pathogenesis, and pathophysiology of postpartum hypertensive disorders. However, there is certain evidence that preeclampsia may in large part be responsible. Women who experienced preeclampsia during pregnancy, although considered cured after delivery and elimination of the placenta, continue to present endothelial and renal dysfunction in the postpartum period. The brain and kidneys are particularly sensitive to this pathological vascular condition, and severe complications may result from their involvement. Large randomized trials are needed to give us the evidence that will allow a timely diagnosis and treatment. Until then, medical providers should increase their knowledge regarding hypertension after delivery because many times there is an underestimation of the complications that can ensue after a misdiagnosed or undertreated postpartum hypertension.

Robotic-Assisted Partial Nephrectomy and Adrenalectomy: Case of a Pheochromocytoma Invading into Renal Parenchyma

Although upper pole renal masses and adrenal masses can usually be distinguished on cross-sectional imaging, large masses can obscure the boundaries between the kidney and adrenal gland. We describe a unique case of an adrenal pheochromocytoma in a 42-year-old female who was referred for robotic partial nephrectomy. During the procedure, the patient developed severe hypertension. The case was aborted, and the workup revealed pheochromocytoma. After appropriate pretreatment, the patient underwent a successful robotic adrenalectomy and partial nephrectomy. Therefore, we recommend screening patients with hypertension and large upper pole masses for pheochromocytoma to better direct preoperative management.

Primary retroperitoneal paraganglioma mimicking a ureteral tumor: a case report and literature review

Paragangliomas (PGLs) arise from chromaffin cells of the extra-adrenal sites along the sympathetic and/or the parasympathetic chain. Majority of the PGLs occur in the abdomen. When retroperitoneal PGLs produce symptoms of compression or invasion of adjacent organs, they could be misdiagnosed as a tumor of adjacent organs. Here, we report a rare case of ureteral obstruction caused by an extra-adrenal retroperitoneal PGL that mimicked a ureteral tumor. A 46-year-old female presented with a 2-year history of hypertension. Routine laboratory tests were unremarkable. The computed tomography (CT) scan showed a hypervascular mass located in the left mid-ureteral section. Ureteropyelography revealed left ureteral obstruction at the level of L4 to L5 vertebrae and hydroureteronephrosis. Cystoscopy confirmed left ureteral obstruction. Based on the clinical and imaging findings, a left ureteral tumor was suspected preoperatively. The tumor was completely resected, and the involved segment of the ureter was removed. No significant enlarged lymph nodes were seen in the pelvic cavity and retroperitoneum. A histopathological examination of the tumor confirmed retroperitoneal PGL partly infiltrating the ureter. The patient's blood pressure returned to the normal range postoperatively. Our case demonstrates the importance of considering extra-adrenal PGL in the differential diagnosis of retroperitoneal tumors.

Genetic and epigenetic differences of benign and malignant pheochromocytomas and paragangliomas (PPGLs)

Pheochromocytomas and paragangliomas (PPGLs) are tumors arising from the adrenal medulla and sympathetic/parasympathetic paraganglia, respectively. According to Th e Cancer Genome Atlas (TCGA), approximately 40% of PPGLs are due to germ line mutations in one of 16 susceptibility genes, and a further 30% are due to somatic alterations in at least seven main genes (VHL, EPAS1, CSDE1, MAX, HRAS, NF1, RET, and possibly KIF1B). Th e diagnosis of malignant PPGL was straight forward in most cases as it was defined as presence of PPGL in non-chromaffin tissues. Accordingly, there is an extreme need for new diagnostic marker(s) to identify tumors with malignant prospective. Th e aim of this study was to review all suggested genetic and epigenetic alterations that are remarkably different between benign and malignant PPGLs. It seems that more than two genetic mutation clusters in PPGLs and other genetic and methylation biomarkers could be targeted for malignancy discrimination in different studies.

A Case of Sudden Death: Subarachnoid Hemorrhage, Pheochromocytoma, Berry Aneurysm

Subarachnoid hemorrhage is a medical emergency. Berry aneurysm rupture is the second most common cause following trauma. Diagnosis is often challenging. Neurogenic heart syndrome often complicates subarachnoid hemorrhage. A concomitant pheochromocytoma can be deadly causing sudden cardiac arrhythmia. Here, we describe a case of subarachnoid hemorrhage with concomitant incidental pheochromocytoma in a relatively young female who died suddenly, diagnosed during autopsy. A 57-year-old Hispanic woman with past medical history of asthma, prediabetes, and uncontrolled hypertension collapsed unexpectedly. She initially had ventricular tachycardia, followed by pulseless electrical activity and finally asystole without response to resuscitation. In the emergency department she was on epinephrine, calcium, naloxone, and tPA with suspected thrombotic stroke. Despite measures, she was pronounced dead. Autopsy revealed subarachnoid hemorrhage due to a ruptured berry aneurysm. Additionally, pheochromocytoma was detected in the right adrenal gland. Subarachnoid hemorrhage has a grave prognosis by itself. This case describes the uncommon detection of pheochromocytoma in the setting of subarachnoid hemorrhage.

An analysis of surveillance screening for SDHB-related disease in childhood and adolescence

Objective Phaeochromocytomas (PCC) and paragangliomas (PGL) are rare in children. A large proportion of these are now understood to be due to underlying germline mutations. Here we focus on succinate dehydrogenase subunit B (SDHB) gene mutation carriers as these tumours carry a high risk of malignant transformation. There remains no current consensus with respect to optimal surveillance for asymptomatic carriers and those in whom the presenting tumour has been resected. Method We undertook a retrospective analysis of longitudinal clinical data of all children and adolescents with SDHB mutations followed up in a single UK tertiary referral centre. This included index cases that pre-dated the introduction of surveillance screening and asymptomatic carriers identified through cascade genetic testing. We also conducted a literature review to inform a suggested surveillance protocol for children and adolescents harbouring SDHB mutations. Results Clinical outcomes of a total of 38 children are presented: 8 index cases and 30 mutation-positive asymptomatic carriers with 175 patient years of follow-up data. Three of the eight index cases developed metachronous disease and two developed metastatic disease. Of the 30 asymptomatic carriers, 3 were found to have PGLs on surveillance screening. Conclusions Surveillance screening was well tolerated in our paediatric cohort and asymptomatic paediatric subjects. Screening can identify tumours before they become secretory and/or symptomatic, thereby facilitating surgical resection and reducing the chance of distant spread. We propose a regular screening protocol commencing at age 5 years in this at-risk cohort of patients.

Can subunit-specific phenotypes guide surveillance imaging decisions in asymptomatic SDH mutation carriers?

OBJECTIVE

With the discovery that familial phaeochromocytoma and paraganglioma syndrome can be caused by mutations in each subunit of the succinate dehydrogenase enzyme (SDH), has come the recognition that mutations in the individual subunits have their own distinct natural histories. Increased genetic screening is leading to the identification of increasing numbers of, mostly asymptomatic, gene mutation carriers and the implementation of screening strategies for these individuals. Yet there is, to date, no international consensus regarding screening strategies for asymptomatic carriers.

DESIGN

A comprehensive PubMed search from 1/1/2000 to 28/2/2018 was undertaken using multiple search terms and subsequently a manual review of references in identified papers to identify all clinically relevant cases and cohorts. In this review, the accumulated, published experience of phenotype and malignancy risks of individual SDH subunits is analysed. Where possible screening results for asymptomatic SDH mutation carriers have been analysed separately to define the penetrance in asymptomatic carriers (asymptomatic penetrance).

RESULTS

The combined data confirms that "asymptomatic penetrance" is highest for SDHD and when there is penetrance, the most likely site to develop a PGL is head and neck (SDHD) and extra-adrenal abdominal (SDHB). However, the risk in SDHB carriers of developing HNPGL is also high (35.5%) and a PCC is low (15.1%), and in SDHD carriers there is a high risk of developing a PCC (35.8%) or abdominal PGL (9.4%) and a small, but significant risk at other sympathetic sites. The data suggest that the risk of malignant transformation is the same for both PCC and extra-adrenal abdominal PGLs (30%-35%) in SDHB carriers. In SDHD carriers, the risk of malignant transformation was highest in HNPGLs (7.5%) and similar for sympathetic sites (3.8%-5.2%).

CONCLUSIONS

Using this data, we suggest surveillance screening of asymptomatic carriers can be tailored to the underlying SDH subunit and review possible surveillance programmes.

Diagnostic and surgical challenges of a giant pheochromocytoma in a resource limited setting-A case report

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Giant pheochromocytomas are rare.

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Diagnosis requires a high index of suspicion.

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Commonly present with a triad of headache, palpitations and hypertension.

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The surgical and anaesthetic team must be prepared to manage hypertensive crisis.

Introduction

Pheochromocytomas are catecholamine producing tumours which arise from chromaffin cells within the adrenal medulla. Patients with these tumours commonly present with a triad of headache, palpitations and hypertension.

Case presentation

We present a case of a 37-year-old male patient who presented with dull left sided abdominal pain and discomfort for 6 weeks. A preoperative Computed tomography (CT) scan showed a huge left suprarenal tumour but urinary vanillylmandelic acid (VMA) were negative. The patient underwent an open surgical resection via an extraperitoneal approach without untoward intraoperative and postoperative events. Histopathological evaluation of the specimen showed a pheochromocytoma with a PASS score of 9. The successful management of the patient highlights the good results of team work despite the limitations of preoperative diagnosis.

Discussion

Giant pheochromocytomas by definition are tumours more than 7 cm in size and are rare. They rarely secrete catecholamines and commonly present with vague abdominal symptoms. A computerized tomogram helps suggest the diagnosis whilst the biochemical workup for pheochromocytoma may be diagnostic. If the tumours are biochemically active, preoperative alpha-blockade is necessary and care must be taken at operation in handling the tumour. The surgical and anaesthetic team must be prepared to manage hypertensive crisis should it occur.

Conclusion

This case brings to the attention of clinicians the need to have a high index of suspicion of a giant pheochromocytoma in a patient presenting with vague abdominal symptoms whose CT scan shows a large retroperitoneal tumour, even in the absence of clinical symptoms and negative or absent biochemical workup.

Patient quality of life and prognosis in multiple endocrine neoplasia type 2

Multiple endocrine neoplasia type 2 (MEN2) refers to the autosomal-dominant neuroendocrine tumour syndromes, MEN type 2A (MEN2A) and MEN type 2B (MEN2B). They are typified by the development of medullary thyroid cancer (MTC), phaeochromocytoma and parathyroid hyperplasia in MEN2A and MTC, phaeochromocytomas, ganglioneuromatosis and skeletal abnormalities in MEN2B. The aggressiveness of MTC is variable according to genotype, and although it is still the major cause of mortality in both conditions, prognosis has improved dramatically in those diagnosed and treated at a young age thanks to predictive genetic testing. Nevertheless, metastatic MTC, ganglioneuromatosis and a variety of other negative clinical and psychosocial impacts on quality of life and/or prognosis in MEN2 persist. In the absence, at the time of writing, of any large-scale research into quality of life specifically in MEN2, this review includes data from patient surveys and anonymised patient anecdotes from the records of the Association for Multiple Endocrine Neoplasia Disorders (AMEND), for whom the authors work. We recommend that these patients are cared for only in centres of expertise able to provide expert diagnosis, treatment and continuity of care, including psychological and transition support. Only in this way can the clinical advances of the last two and half decades be built upon further to ensure that the care of these complex, lifelong patients can be considered truly holistic.

When should genetic testing be performed in patients with neuroendocrine tumours?

Neuroendocrine tumours (NETs) are a heterogenous group of tumours arising from neuroendocrine cells in several sites around the body. They include tumours of the gastroenteropancreatic system, phaeochromocytoma and paraganglioma and medullary thyroid cancer. In recent years, it has become increasingly apparent that a number of these tumours arise as a result of germline genetic mutations and are inherited in an autosomal dominant pattern. The number of genes implicated is increasing rapidly. Identifying which patients are likely to have a germline mutation enables clinicians to counsel patients adequately about their future disease risk, and allows for earlier detection of at-risk patients through family screening. The institution of screening and surveillance programmes may in turn lead to a major shift in presentation patterns for some of these tumours. In this review, we examine the features which may lead a clinician to suspect that a patient may have an inherited cause of a NET and we outline which underlying conditions should be suspected. We also discuss what type of screening may be appropriate in a variety of situations.

A Giant Adrenal Mass in a Super Obese Patient

Giant pheochromocytomas (Pheo) are rare entities requiring clinical suspicion coupled with strategic diagnostic evaluation to confirm the diagnosis. The majority of cases are discovered incidentally. The diagnosis consists of biochemical evaluation and imaging study to localize the mass. Pathological examination confirms the diagnosis. The female patient in this case report presented with chest pain, palpitation of three weeks duration and was found on evaluation to have an abdominal mass concerning for pheochromocytoma. She was treated with surgical resection. The pheo measured 20.5 x 18 x 10 cm and weighed 2,582 grams. Pathological examination confirmed the diagnosis of pheochromocytoma.

Risk factors for prolonged hypotension in patients with pheochromocytoma undergoing laparoscopic adrenalectomy: a single-center retrospective study

Prolonged hypotension during pheochromocytoma resection is a significant complication. We sought to investigate the predictors of prolonged hypotension in patients with pheochromocytoma undergoing laparoscopic adrenalectomy (LA). Patients with pheochromocytoma who underwent LA between 2012 and 2015 were surveyed. Patients were considered to have prolonged hypotension if they had a mean arterial blood pressure <60 mmHg or required ≥30 consecutive minutes of catecholamine support intraoperatively. Among 123 patients, 54 (43.9%) developed prolonged hypotension requiring ≥30 consecutive minutes of catecholamine support. Compared with patients with nonprolonged hypotension, those with prolonged hypotension had higher levels of urinary norepinephrine (P = 0.011), epinephrine (P < 0.001), and dopamine (P = 0.019) preoperatively, and a higher incidence of vital organ injury postoperatively (P = 0.039). Multivariate logistic analysis showed that independent predictors for prolonged hypotension were multiples of the normal reference upper limit value of urinary epinephrine (odds ratio, 1.180; 95% confidence interval, 1.035–1.345) and dopamine (odds ratio, 4.375; 95% confidence interval, 1.207–15.855). The levels of preoperative urinary epinephrine and dopamine are clinical predictors for prolonged hypotension in patients with pheochromocytoma undergoing LA. Using these parameters, clinicians can assess and manage this patient population more effectively.

Radiological Surveillance Screening in Asymptomatic Succinate Dehydrogenase Mutation Carriers

There has been a significant increase in the availability of testing for pheochromocytoma and paraganglioma (PPGL) germline susceptibility genes. As more patients with genetic mutations are identified, cascade genetic testing of family members is also increasing. This results in identifying genetic predispositions at a much earlier age. With our current understanding of familial PPGL syndromes, lifelong surveillance is required. This review focuses on carriers of succinate dehydrogenase (SDH) mutations. For genetic testing to be proven worthwhile, the results must be used for patient benefit. For SDHx mutations, this should equate to a surveillance program that is safe and removes as much uncertainty around diagnosis as possible. Early identification of these tumors is the goal of any surveillance program, as surgical resection is the mainstay of treatment with curative intent to prevent the morbidity and mortality consequences associated with catecholamine excess, in addition to the risk of malignancy. Modality and frequency of surveillance imaging and how to engage individuals in the process of surveillance remain controversial questions. The data reviewed here and the cumulative advice supports the avoidance of using radiation-exposing imaging in this group of individuals that require lifelong screening.

Accuracy of recommended sampling and assay methods for the determination of plasma-free and urinary fractionated metanephrines in the diagnosis of pheochromocytoma and paraganglioma: a systematic review

PURPOSE

To determine the accuracy of biochemical tests for the diagnosis of pheochromocytoma and paraganglioma.

METHODS

A search of the PubMed database was conducted for English-language articles published between October 1958 and December 2016 on the biochemical diagnosis of pheochromocytoma and paraganglioma using immunoassay methods or high-performance liquid chromatography with coulometric/electrochemical or tandem mass spectrometric detection for measurement of fractionated metanephrines in 24-h urine collections or plasma-free metanephrines obtained under seated or supine blood sampling conditions.

RESULTS

Application of the Standards for Reporting of Diagnostic Studies Accuracy Group criteria yielded 23 suitable articles. Summary receiver operating characteristic analysis revealed sensitivities/specificities of 94/93% and 91/93% for measurement of plasma-free metanephrines and urinary fractionated metanephrines using high-performance liquid chromatography or immunoassay methods, respectively. Partial areas under the curve were 0.947 vs. 0.911. Irrespective of the analytical method, sensitivity was significantly higher for supine compared with seated sampling, 95 vs. 89% (p < 0.02), while specificity was significantly higher for supine sampling compared with 24-h urine, 95 vs. 90% (p < 0.03). Partial areas under the curve were 0.942, 0.913, and 0.932 for supine sampling, seated sampling, and urine. Test accuracy increased linearly from 90 to 93% for 24-h urine at prevalence rates of 0.0-1.0, decreased linearly from 94 to 89% for seated sampling and was constant at 95% for supine conditions.

CONCLUSIONS

Current tests for the biochemical diagnosis of pheochromocytoma and paraganglioma show excellent diagnostic accuracy. Supine sampling conditions and measurement of plasma-free metanephrines using high-performance liquid chromatography with coulometric/electrochemical or tandem mass spectrometric detection provides the highest accuracy at all prevalence rates.

Outcomes of annual surveillance imaging in an adult and paediatric cohort of succinate dehydrogenase B mutation carriers

OBJECTIVE

For 'asymptomatic carriers' of the succinate dehydrogenase subunit B (SDHB) gene mutations, there is currently no consensus as to the appropriate modality or frequency of surveillance imaging. We present the results of a surveillance programme of SDHB mutation carriers.

DESIGN

Review of clinical outcomes of a surveillance regimen in patients identified to have an SDHB gene mutation, based on annual MRI, in a single UK tertiary referral centre.

PATIENTS

A total of 92 patients were identified with an SDHB gene mutation. a total of 27 index patients presented with symptoms, and 65 patients were identified as asymptomatic carriers.

MEASUREMENTS

Annual MRI of the abdomen, with alternate year MRI of the neck, thorax and pelvis. Presence of an SDHB-related tumour included paraganglioma (PGL), phaeochromocytoma (PCC), renal cell carcinoma (RCC) and gastrointestinal stromal tumour (GIST).

RESULTS

A total of 43 PGLs, eight PCCs and one RCC occurred in the 27 index patients (23 solitary, four synchronous, five metachronous). A further 15 SDHB-related tumours (11 PGLs, three RCCs, one GIST) were identified in the asymptomatic carriers on surveillance screening (25% of screened carriers): 10 on the first surveillance imaging and five on subsequent imaging 2-6 years later. A total of 11 patients had malignant disease.

CONCLUSIONS

SDHB-related tumours are picked up as early as 2 years after initial negative surveillance scan. We believe the high malignancy rate and early identification rate of tumours justifies the use of 1-2 yearly imaging protocols and MRI-based imaging could form the mainstay of surveillance in this patient group thereby minimizing radiation exposure.

Absence of BRAF mutation in pheochromocytoma and paraganglioma

Pheochromocytomas and Paragangliomas (PHEO/PARA) are rare endocrine tumors originating from the adrenal medulla. More than 20 genes are involved in the tumorigenesis of these tumors, but a substantial part of the causative genetic events remains unexplained. A recent study has reported the presence of the activating BRAF V600E mutation in PCC, suggesting a role for BRAF activation in tumor development. Other studies have not find this mutation. This study investigates the occurrence of the BRAF V600E mutation in these tumors.A cohort of 64 PHEO/PARA were screened for the BRAF V600E mutation using direct Sanger sequencing and QRT-PCR.All cases investigated displayed wild-type without V600E BRAF mutationTaken together with all previously screened tumors up to date, only 1 V600E BRAF mutation has been found among 427 PCCs. These findings imply that the V600E BRAF mutation is a rare event in PHEO/PARA.

Diagnosis and Management of Hereditary Phaeochromocytoma and Paraganglioma

About 30% of phaeochromocytomas or paragangliomas are genetic. Whilst some individuals will have clinical features or a family history of inherited cancer syndrome such as neurofibromatosis type 1 (NF1) or multiple endocrine neoplasia 2 (MEN2), the majority will present as an isolated case. To date, 14 genes have been described in which pathogenic mutations have been demonstrated to cause paraganglioma or phaeochromocytoma . Many cases with a pathogenic mutation may be at risk of developing further tumours. Therefore, identification of genetic cases is important in the long-term management of these individuals, ensuring that they are entered into a surveillance programme. Mutation testing also facilitates cascade testing within the family, allowing identification of other at-risk individuals. Many algorithms have been described to facilitate cost-effective genetic testing sequentially of these genes, with phenotypically driven pathways. New genetic technologies including next-generation sequencing and whole-exome sequencing will allow much quicker, cheaper and extensive testing of individuals in whom a genetic aetiology is suspected.

(111)In-octreotide SPECT-CT in head and neck paragangliomas

Head and neck paragangliomas are rare neuroendocrine tumors expressing somatostatin receptors on their cell surface, particularly subtype 2. Due to this distinctive feature, images can be obtained in Nuclear Medicine using synthetic analogues of somatostatin, mainly octreotide, which allow selective display by planar scintigraphy, SPECT-CT or PET-CT imaging after radiolabeling with (111)In or (68)Ga. Three cases have been selected and presented from a series of patients that illustrate the utility of SPECT-CT studies with (111)In-octreotide in the diagnosis and monitoring of this type of tumor. These are characterization at initial diagnosis, staging, and detection of local recurrence or metastasis, with added value with respect to anatomical images (nuclear magnetic resonance, computed axial tomography, angiography), for example in the differentiation between functional tissue or scar in patients who had previously undergone surgery.

The evaluation and treatment of endocrine forms of hypertension

Endocrine hypertension is an important secondary form of hypertension, identified in between 5% and 10% of general hypertensive population. Primary aldosteronism is the most common cause of endocrine hypertension, accounting for 1%-10% in uncomplicated hypertension and 7%-20% in resistant hypertension. Other less common causes of endocrine hypertension include Cushing syndrome, pheochromocytoma, thyroid disorders, and hyperparathyroidism. Diagnosis requires a high index of suspicion and the use of appropriate screening tests based on clinical presentation. Failure to make proper diagnosis may lead to catastrophic complications or irreversible hypertensive target organ damage. Accordingly, patients who are suspected to have endocrine hypertension should be referred to endocrinologists or hypertension specialists who are familiar with management of the specific endocrine disorders.

Extra-adrenal paraganglioma presenting as acute chest pain mimicking acute myocardial infarction in a 10-year-old boy

Extraadrenal paragangliomas are rare pediatric tumors with variable symptoms that cause difficultly in diagnosis and delayed treatment. We report the case of a 10-year-old boy who presented to the pediatric emergency department with acute chest pain and dyspnea mimicking a non-ST-segment elevation acute myocardial infarction. He was subsequently found to have an extraadrenal paraganglioma after a series of imaging and laboratory examinations. The mass was subsequently removed, and the diagnosis of extraadrenal paraganglioma was confirmed histologically. Acute coronary syndrome as the presenting feature of extraadrenal paragangliomas in pediatric population is an even rarer clinical entity.

High incidence of morbidity following resection of metastatic pheochromocytoma in the spine

Pheochromocytomas of the spine are uncommon and require careful preoperative planning. The authors retrospectively reviewed the charts of 5 patients with metastatic spinal pheochromocytoma who had undergone surgical treatment over the past 10 years at their medical center. They reviewed patient age, history of pheochromocytoma resection, extent and location of metastases, history of alpha blockage, surgical level, surgical procedure, postoperative complications, tumor recurrence, and survival. Metastases involved the cervical (1 patient), thoracic (3 patients), and lumbar (2 patients) levels. Preoperative treatment included primary pheochromocytoma resection, chemotherapy, alpha blockade, embolization, and radiation. Three patients had tumor recurrence, and 2 underwent 2-stage reoperations for tumor extension. Hemodynamic complications were common: 2 patients developed pulseless electrical activity arrest within 4 months after surgery, 1 patient had profound postoperative tachycardia with fever and an elevated creatine kinase level, and 1 patient experienced transient postoperative hypotension and paraplegia. One patient died of complications related to disseminated cerebral and spinal disease.

With careful preoperative and surgical management, patients with symptomatic metastatic spinal pheochromocytoma can benefit from aggressive surgical treatment. Postoperative cardiovascular complications are common even months after surgery, and patients should be closely monitored long term.

Noncoding RNAs in endocrine malignancy

Only recently has it been uncovered that the mammalian transcriptome includes a large number of noncoding RNAs (ncRNAs) that play a variety of important regulatory roles in gene expression and other biological processes. Among numerous kinds of ncRNAs, short noncoding RNAs, such as microRNAs, have been extensively investigated with regard to their biogenesis, function, and importance in carcinogenesis. Long noncoding RNAs (lncRNAs) have only recently been implicated in playing a key regulatory role in cancer biology. The deregulation of ncRNAs has been demonstrated to have important roles in the regulation and progression of cancer development. In this review, we describe the roles of both short noncoding RNAs (including microRNAs, small nuclear RNAs, and piwi-interacting RNAs) and lncRNAs in carcinogenesis and outline the possible underlying genetic mechanisms, with particular emphasis on clinical applications. The focus of our review includes studies from the literature on ncRNAs in traditional endocrine-related cancers, including thyroid, parathyroid, adrenal gland, and gastrointestinal neuroendocrine malignancies. The current and potential future applications of ncRNAs in clinical cancer research is also discussed, with emphasis on diagnosis and future treatment.

Biochemical diagnosis of phaeochromocytoma using plasma-free normetanephrine, metanephrine and methoxytyramine: importance of supine sampling under fasting conditions

OBJECTIVE

To document the influences of blood sampling under supine fasting versus seated nonfasting conditions on diagnosis of phaeochromocytomas and paragangliomas (PPGL) using plasma concentrations of normetanephrine, metanephrine and methoxytyramine.

DESIGN AND METHODS

Biochemical testing for PPGL was performed on 762 patients at six centres, two of which complied with requirements for supine sampling after an overnight fast and four of which did not. Phaeochromocytomas and paragangliomas were found in 129 patients (67 noncompliant, 62 compliant) and not in 633 patients (195 noncompliant, 438 compliant).

RESULTS

Plasma concentrations of normetanephrine and methoxytyramine did not differ between compliant and noncompliant sampling conditions in patients with PPGL but were 49-51% higher in patients without PPGL sampled under noncompliant compared with compliant conditions. The 97·5 percentiles of distributions were also higher under noncompliant compared with compliant conditions for normetanephrine (1·29 vs 0·79 nmol/l), metanephrine (0·49 vs 0·41 nmol/l) and methoxytyramine (0·42 vs 0·18 nmol/l). Use of upper cut-offs established from seated nonfasting sampling conditions resulted in substantially decreased diagnostic sensitivity (98% vs 85%). In contrast, use of upper cut-offs established from supine fasting conditions resulted in decreased diagnostic specificity for testing under noncompliant compared with compliant conditions (71% vs 95%).

CONCLUSIONS

High diagnostic sensitivity of plasma normetanephrine, metanephrine and methoxytyramine for the detection of PPGL can only be guaranteed using upper cut-offs of reference intervals established with blood sampling under supine fasting conditions. With such cut-offs, sampling under seated nonfasting conditions can lead to a 5·7-fold increase in false-positive results necessitating repeat sampling under supine fasting conditions.

Functional paraganglioma

Paraganglioma are tumours arising from neural crest cells of the sympathetic and parasympathetic paraganglia. Functional paraganglioma presents with symptoms of catecholamine excess that includes hypertension, flushing, diaphoresis, etc. Non-functional paraganglioma are usually found incidentally during imaging studies. Early diagnoses of functional paraganglioma are important because their removal is often curative. We present the case of a young man who presented with hypertensive crisis and severe headache, who was later found to have functional paraganglioma.

Integrative genetic characterization and phenotype correlations in pheochromocytoma and paraganglioma tumours

BACKGROUND

About 60% of Pheochromocytoma (PCC) and Paraganglioma (PGL) patients have either germline or somatic mutations in one of the 12 proposed disease causing genes; SDHA, SDHB, SDHC, SDHD, SDHAF2, VHL, EPAS1, RET, NF1, TMEM127, MAX and H-RAS. Selective screening for germline mutations is routinely performed in clinical management of these diseases. Testing for somatic alterations is not performed on a regular basis because of limitations in interpreting the results.

AIM

The purpose of the study was to investigate genetic events and phenotype correlations in a large cohort of PCC and PGL tumours.

METHODS

A total of 101 tumours from 89 patients with PCC and PGL were re-sequenced for a panel of 10 disease causing genes using automated Sanger sequencing. Selected samples were analysed with Multiplex Ligation-dependent Probe Amplification and/or SNParray.

RESULTS

Pathogenic genetic variants were found in tumours from 33 individual patients (37%), 14 (16%) were discovered in constitutional DNA and 16 (18%) were confirmed as somatic. Loss of heterozygosity (LOH) was observed in 1/1 SDHB, 11/11 VHL and 3/3 NF1-associated tumours. In patients with somatic mutations there were no recurrences in contrast to carriers of germline mutations (P = 0.022). SDHx/VHL/EPAS1 associated cases had higher norepinephrine output (P = 0.03) and lower epinephrine output (P<0.001) compared to RET/NF1/H-RAS cases.

CONCLUSION

Somatic mutations are frequent events in PCC and PGL tumours. Tumour genotype may be further investigated as prognostic factors in these diseases. Growing evidence suggest that analysis of tumour DNA could have an impact on the management of these patients.

Phaeochromocytoma [corrected] crisis

Phaeochromocytoma [corrected] crisis is an endocrine emergency associated with significant mortality. There is little published guidance on the management of phaeochromocytoma [corrected] crisis. This clinical practice update summarizes the relevant published literature, including a detailed review of cases published in the past 5 years, and a proposed classification system. We review the recommended management of phaeochromocytoma [corrected] crisis including the use of alpha-blockade, which is strongly associated with survival of a crisis. Mechanical circulatory supportive therapy (including intra-aortic balloon pump or extra-corporeal membrane oxygenation) is strongly recommended for patients with sustained hypotension. Surgical intervention should be deferred until medical stabilization is achieved.