Pheochromocytoma: state-of-the-art and future prospects

Laparoscopic resection of retrocaval paraganglioma

OBJECTIVES

Definitive treatment of paraganglioma is by surgical resection. Laparoscopic resection of the paraganglioma presents a unique surgical challenge due to inherent risks associated with excessive catecholamine release during surgical manipulation and variable anatomic presentation. In this report, we present our experience with the laparoscopic resection of the retrocaval paraganglioma.

METHODS

Between October 2001 and November 2007, 2 patients underwent the laparoscopic resection of a retrocaval paraganglioma. In both cases, the tumors were located just behind the inferior vena cava (IVC) without evidence of vessel-wall invasion. The maximum diameter of the tumor was 47 and 44 mm, respectively. There was extrinsic compression of the IVC in an anterior direction by the tumor. To expose the tumor surface completely, the IVC was mobilized medially. Thereafter, we proceeded with dissection of the posterior attachment of the tumor by using a Harmonic Scalpel (Ethicon, Cincinnati, OH). Finally, the tumor and the right adrenal gland were extracted in an endobag.

RESULTS

In both cases, the tumors were successfully removed laparoscopically without the need for conversion or blood transfusion. The operative time was 440 and 195 minutes, respectively. There were no significant postoperative complications.

CONCLUSIONS

To our knowledge, this is the first report of the laparoscopic resection of a retrocaval paraganglioma. For the resection of a paraganglioma, in this location, laparoscopy has the advantage of precise visualization, which helps to resect the tumor completely. Laparoscopic resection of a paraganglioma, despite the high level of compression of the IVC, is a feasible, reproducible technique with appropriate preoperative planning.

Positron emission tomography with 18F-fluorodeoxyglucose is a useful tool for the diagnosis of pheochromocytomas without distant metastasis, where malignancy is suspected on the basis of histopathologic analysis

A 69-year-old woman, who had been undergoing treatment for hypertension, was admitted to the hospital for the evaluation of a tumor in the right adrenal gland and of episodic hypertension. She was diagnosed with pheochromocytoma on the basis of elevated urine catecholamine and metabolite concentrations and positron emission tomography (PET) results; however, the results of I-metaiodobenzylguanidine (I-MIBG) scintigraphy were negative. The patient underwent laparoscopic right adrenalectomy. Malignancy was suspected on the basis of histopathologic studies. After surgery, the elevated catecholamine and metabolite concentrations and the blood pressure returned to normal; furthermore, the symptoms, including severe headache, reduced. The authors report a case of pheochromocytoma that was suspected to be malignant on the basis of histopathologic analysis and was detected by F-fluorodeoxyglucose (FDG)-PET but not by MIBG. Thus, FDG-PET may be a prognostic marker for malignant pheochromocytomas with or without metastasis.

Granins and their derived peptides in normal and tumoral chromaffin tissue: Implications for the diagnosis and prognosis of pheochromocytoma

Pheochromocytomas are rare catecholamine-secreting tumors that arise from chromaffin tissue within the adrenal medulla and extra-adrenal sites. Typical clinical manifestations are sustained or paroxysmal hypertension, severe headaches, palpitations and sweating resulting from hormone excess. However, their presentation is highly variable and can mimic many other diseases. The diagnosis of pheochromocytomas depends mainly upon the demonstration of catecholamine excess by 24-h urinary catecholamines and metanephrines or plasma metanephrines. Occurrence of malignant pheochromocytomas can only be asserted by imaging of metastatic lesions, which are associated with a poor survival rate. The characterization of tissue, circulating or genetic markers is therefore crucial for the management of these tumors. Proteins of the granin family and their derived peptides are present in dense-core secretory vesicles and secreted into the bloodstream, making them useful markers for the identification of neuroendocrine cells and neoplasms. In this context, we will focus here on reviewing the distribution and characterization of granins and their processing products in normal and tumoral chromaffin cells, and their clinical usefulness for the diagnosis and prognosis of pheochromocytomas. It appears that, except SgIII, all members of the granin family i.e. CgA, CgB, SgII, SgIV-SgVII and proSAAS, and most of their derived peptides are present in adrenomedullary chromaffin cells and in pheochromocytes. Moreover, besides the routinely used CgA test assays, other assays have been developed to measure concentrations of tissue and/or circulating granins or their derived peptides in order to detect the occurrence of pheochromocytomas. In most cases, elevated levels of these entities were found, in correlation with tumor occurrence, while rarely discriminating between benign and malignant neoplasms. Nevertheless, measurement of the levels of granins and derived peptides improves the diagnostic sensitivity and may therefore provide a complementary tool for the management of pheochromocytomas. However, the existing data need to be substantiated in larger groups of patients, particularly in the case of malignant disease.

Chromogranin A assay in clinical practice

Chromogranins belong to the family of secretory chromogranin and secretogranin proteins. They are found in secretory vesicles throughout the neuroendocrine system. Chromogranin A (CgA) is the main component. CgA acts as a prohormone submitted to processes of degradation through which active peptides are generated. CgA has auto, para and endocrine functions. It is widely used as an immunohistochemical marker. Despite the lack of international standardization, and the lack of an accurate definition of the diagnostic cut-off levels, some CgA assays are reliable. Numerous studies have suggested that CgA determination may be of interest for the diagnosis and the follow-up of various endocrine tumors. Plasma levels of this general marker are proportional to tumor mass. The localization of the primitive tumor, the presence of associated hormonal secretions and possible renal failure and/or hypergastrinemia must be taken into consideration for proper interpretation of CgA levels. New clinical indications are emerging for the evaluation of stress in intensive care units and the assessment of cardiovascular risk. New assays estimating the concentration of active peptides are under development.

Comparison of two preoperative medical management strategies for laparoscopic resection of pheochromocytoma

OBJECTIVES

To compare the intraoperative and postoperative course of patients undergoing laparoscopic pheochromocytoma resection at 2 institutions (Mayo Clinic and Cleveland Clinic) with differing approaches to preoperative preparation. Patients undergoing adrenalectomy for pheochromocytoma typically undergo a preoperative preparation to normalize their blood pressure and intravascular volume. However, no consensus has been reached regarding the best preoperative preparation regimen.

METHODS

A retrospective chart review was performed of 50 Mayo Clinic patients and 37 Cleveland Clinic patients who had undergone laparoscopic pheochromocytoma resection. Mayo Clinic predominantly used the long-lasting nonselective alpha(1,2) antagonist phenoxybenzamine, and Cleveland Clinic predominately used selective alpha(1) blockade. Data regarding the intraoperative hemodynamics and postoperative complications were collected.

RESULTS

Almost all patients at Mayo Clinic received phenoxybenzamine (98%). At Cleveland Clinic, the predominant treatment (65%) was selective alpha(1) blockade (doxazosin, terazosin, or prazosin). Intraoperatively, patients at Cleveland Clinic had a greater maximal systolic blood pressure (209 +/- 44 mm Hg versus 187 +/- 30 mm Hg, P = .011) and had received a greater amount of intravenous crystalloid (median 5000, interquartile range 3400-6400, versus median 2977, interquartile range 2000-3139; P <.010) and colloid (median 1000, interquartile range 500-1000, versus median 0, interquartile range 0-0; P <.001). At Mayo Clinic, more patients had received phenylephrine (56.0% versus 27.0%, P = .009). No differences were found in the postoperative surgical outcomes, and the hospital stay was comparable between the 2 groups.

CONCLUSIONS

Differences in the preoperative preparation and intraoperative management were associated with differences in intraoperative hemodynamics but not with clinically significant outcomes in patients undergoing laparoscopic adrenalectomy for pheochromocytoma at 2 large tertiary care centers.

A current review of the etiology, diagnosis, and treatment of pediatric pheochromocytoma and paraganglioma

CONTEXT

Pheochromocytomas and paragangliomas (PHEO/PGL) are neuroendocrine tumors that arise from sympathetic and parasympathetic paraganglia. Diagnosed rarely during childhood, PHEO/PGL are nonetheless important clinical entities, particularly given our evolving understanding of their pathophysiology.

EVIDENCE ACQUISITION

We identified articles through the U.S. National Library of Medicine by using the search terms pheochromocytoma and paraganglioma. Results were narrowed to manuscripts that included children and studies related to the genetics of PHEO/PGL. Web-based resources for genetic disorders were also used. For all articles, we performed subsequent reference searches and verification of source data.

EVIDENCE SYNTHESIS

Up to 20% of PHEO/PGL are diagnosed in children. Most are functional tumors, and clinical presentation includes symptoms related to catecholamine hypersecretion and/or tumor mass effect. Increasingly, PHEO/PGL are identified during presymptomatic screening in children with genetic syndromes associated with PHEO/PGL (multiple endocrine neoplasia type 2, von Hippel-Lindau disease, and the paraganglioma syndromes). Plasma and/or urine metanephrines are the best diagnostic test for a functional tumor, and the management of pediatric patients is similar to adults. Genetic counseling should be undertaken in all cases. Although most pediatric PHEO/PGL are benign, these tumors can occasionally metastasize, a condition for which no curative treatment exists.

CONCLUSIONS

Although PHEO/PGL are rarely diagnosed during childhood, the pediatric provider should be able to recognize and screen for such tumors, particularly in the context of a known genetic predisposition. Optimal care of these children includes a multidisciplinary team approach at centers experienced in the evaluation and treatment of these uncommon yet fascinating endocrine neoplasms.

[High percentage of adrenergic symptoms in extraadrenal chromaffin tumors]

Descriptive retrospective study of 14 patients with paragangliomas (PGL) attended in the University Hospital of Vigo (Pontevedra) during the last 25 years to evaluating their characteristics and neuroendocrine potential.

RESULTS

71.4% were diagnosed due to mass tumoral effect, 21.4% due to adrenergic symptoms and 7.1% incidentally. Regarding to symptoms and signs 66.7% of PGL Simpatic (PGLS) and 40% of PGL Parasimpatic (PGLPS) presented adrenergic symptoms. Urine catecholamine analysis was carried out to 4 PGLS and high levels were found in all patients. The tumoral size reached a mean value of 37.8+/-18.9 mm, there were not differences found between both types of tumors. Inmunohistoquimia showed positive Chromogranine A stain in all patients. Two PGLS were maligns. Eleven patients had positive outcome, 2 PGLS died, and 1 PGLPS remains not cured.

CONCLUSIONS

High percentage of patients had clinical manifestations related to catecholamine hyperproduction. We believe that due to the risk related to surgical treatment, malignance, multiple location and family associations, it would be advisable to carry out a complete examination prior to surgery.

Pheochromocytoma associated with neurofibromatosis type 1: concepts and current trends

Background

Neurofibromatosis Type 1(NF-1) has autosomal dominant inheritance with complete penetrance, variable expression and a high rate of new mutation. Pheochromocytoma occurs in 0.1%-5.7% of patients with NF-1.

Case presentation

We present the case of a 37-year-old patient with laparoscopically resected pheochromocytoma. He was investigated for hypertension, flushing and ectopic heart beat. Abdominal CT and MRI revealed a mass measuring 8 × 4 cm in the right adrenal gland. The diagnosis of pheochromocytoma was confirmed by elevated 24-hour urine levels of VMA, metanephrines and catecholamines as well as positive MIBG scan. The patient presented with classic clinical features of NF-1, which was confirmed by pathologic evaluation of an excised skin nodule. The patient underwent laparoscopic right adrenalectomy through a transabdominal approach and was discharged on the second postoperative day, being normotensive. The patient is normotensive without antihypertensive therapy 11 years after the procedure.

Conclusion

Nowadays in the era of laparoscopy, patients with pheochromocytoma reach the operating theatre easier than in the past. Despite, the feasibility and oncological efficacy of the laparoscopic approach to the adrenals, continued long term follow-up is needed to establish the minimally invasive technique as the preferred approach. Furthermore, these patients should be further investigated for other neoplasias and stigmata of other neurocutaneous syndromes, taking into account the association of the familial pheochromo-cytoma with other familial basis inherited diseases.

A rare paraganglioma with skull and brain metastasis

Cerebral metastasis rarely occurs in paraganglioma. We report the first patient, to our knowledge, with both skull and brain metastases, who underwent abdominal and skull, as well as brain lesion resection over 5 years, with a satisfactory outcome at the 10-year follow-up. We describe the characteristics and explore the possible underlying mechanisms to assist in future diagnosis and treatment of paraganglioma.

Pheochromocytoma crisis after a dexamethasone suppression test for adrenal incidentaloma

A 61-year-old woman was referred to our department for evaluation of an incidental adrenal mass. An abdominal CT scan revealed a 4.1 cm right adrenal mass. The patient had been diagnosed with hypertension 7 years earlier and had taken antihypertensive medications intermittently. Her physical examination demonstrated a round face, central obesity, and mild hypertension. Serum catecholamines, renin, aldosterone, ACTH and 24-h urine-free cortisol, vanillylmandelic acid levels were within normal limits. However, serum cortisol level was markedly elevated and the circadian rhythm was disturbed. Successive low-dose and high-dose dexamethasone suppression tests were ordered for evaluation of a functioning adrenal incidentaloma. About 2 h after taking the second dose of 2 mg dexamethasone, she suddenly developed nausea and vomiting, palpitations, and anxiety with severe hypertension. On the same day, we measured serum catecholamines, which were markedly elevated. An elective laparoscopic right adrenalectomy was performed and pathologic examination confirmed the diagnosis of pheochromocytoma. One week after surgery, serum and urine catecholamine levels returned to normal. The patient has remained normotensive without any medications and clinically well. Patients with adrenal incidentalomas may have a functional mass that does not always manifest as a full symptomatic disease. During the investigation of adrenal incidentalomas, pheochromocytoma should ideally be ruled out before administering corticosteroids.

Risk Factors for Hemodynamic Instability during Surgery for Pheochromocytoma

BACKGROUND

Surgery on pheochromocytoma carries a risk for hemodynamic (HD) instability. The aim of this study was to identify preoperative risk factors for intraoperative HD instability. In addition, efficacy of pretreatment with the alpha-adrenergic receptor (alpha) antagonists phenoxybenzamine (PXB) and doxazosin (DOX) was compared with respect to reduction of intraoperative HD instability.

METHODS

Seventy-three patients operated in Erasmus Medical Center between 1995 and 2007 were included. Parameters studied were catecholamine type and concentration, tumor diameter, mean arterial pressure (MAP) before and after (MAP(alpha)) pretreatment with alpha-antagonist, postural fall in blood pressure (BP) after pretreatment, type of alpha-blockade, type of operation, and presence of a familial polytumor syndrome. HD instability was assessed by measuring the number and time period MAP was below 60 mm Hg and systolic BP (SBP) was above 160 mm Hg.

RESULTS

A correlation was found between the intraoperative time periods of SBP above 160 mm Hg and plasma norepinephrine levels (r = 0.23; P < 0.05), tumor diameter (r = 0.36; P < 0.01), and postural BP fall (r = 0.30; P < 0.05). MAP at presentation and after alpha-blockade above 100 mm Hg (BP, 130/85 mm Hg) was related to more and longer episodes with a SBP above 160 mm Hg (P < 0.01). Type of operation or alpha-blockade and presence of a familial polytumor syndrome were not related to intraoperative HD instability. Postoperative MAP was lower in the DOX group than in the PXB group (P < 0.05).

CONCLUSION

Risk factors for HD instability during surgery for pheochromocytoma include a high plasma NE concentration, larger tumor size, more profound postural BP fall after alpha-blockade, and a MAP above 100 mm Hg (130/85 mm Hg). Efficacy for preventing HD instability was identical for PXB and DOX.

Low sensitivity of glucagon provocative testing for diagnosis of pheochromocytoma

CONTEXT

Pheochromocytomas can usually be confirmed or excluded using currently available biochemical tests of catecholamine excess. Follow-up tests are, nevertheless, often required to distinguish false-positive from true-positive results. The glucagon stimulation test represents one such test; its diagnostic utility is, however, unclear.

OBJECTIVE

The aim of the study was to determine the diagnostic power of the glucagon test to exclude or confirm pheochromocytoma.

DESIGN, SETTING, AND SUBJECTS

Glucagon stimulation tests were carried out at three specialist referral centers in 64 patients with pheochromocytoma, 38 patients in whom the tumor was excluded, and in a reference group of 36 healthy volunteers.

MAIN OUTCOME MEASURES

Plasma concentrations of norepinephrine and epinephrine were measured before and after glucagon administration. Several absolute and relative test criteria were used for calculating diagnostic sensitivity and specificity. Expression of the glucagon receptor was examined in pheochromocytoma tumor tissue from a subset of patients.

RESULTS

Larger than 3-fold increases in plasma norepinephrine after glucagon strongly predicted the presence of a pheochromocytoma (100% specificity and positive predictive value). However, irrespective of the various criteria examined, glucagon-provoked increases in plasma catecholamines revealed the presence of the tumor in less than 50% of affected patients. Diagnostic sensitivity was particularly low in patients with pheochromocytomas due to von Hippel-Lindau syndrome. Tumors from these patients showed no significant expression of the glucagon receptor.

CONCLUSION

The glucagon stimulation test offers insufficient diagnostic sensitivity for reliable exclusion or confirmation of pheochromocytoma. Because of this and the risk of hypertensive complications, the test should be abandoned in routine clinical practice.

Pheochromocytoma and paraganglioma

Pheochromocytoma is a very special kind of tumor full of duplicity. On the one hand it represents its own microworld with unique clinical, biochemical and pathological features, while on the other it constitutes a tremendously significant part of whole body system, playing a vital role for practically every organ system. It has a very special character - sometimes like a child it can be sweet and predictable, while at times it can behave like a deadly wild beast, crashing and tearing everything on its path in a fierce rage. It also consists of the amazingly intelligent neuroendocrine cells that possess a magical ability to make miraculous substances of many kinds. But most of all, it is a system that is able to drive our curiosity and the itch of "Cogito, ergo sum" to limitless depths and year by year it still amazes us with new and unexpected discoveries that move our understanding of multiple pathways and metabolic events closer to the ultimate truth. Recent discoveries of succinate dehydrogenase (SHD) and prolyl hydroxylase (PHD) mutations, for example, propelled our understanding of neuroendocrine tumorigenesis as a whole, as well as physiology of mitochondrial respiratory chain and phenomenon of pseudohypoxia in particular. Good old discoveries make their way from dusty repositories to shine with new meaning, appropriate for the current level of knowledge. This acquired wisdom makes us better physicians - knowing the specific expression makeup of catecholamine transporters, GLUTs and SRIFs allows for better tailored imaging and therapeutic manipulations. There are still long ways to go, keeping in mind that pheochromocytoma is but so very special, and we are optimistic and expect many great things to come.

Laparoscopic excision of a familial paraganglioma

Pheochromocytomas are rare neuroendocrine tumors that secrete catecholamines and usually arise from the adrenal medulla. Catecholamine-producing tumors that arise from extra-adrenal chromaffin tissue are referred to as paragangliomas, or extra-adrenal pheochromocytomas. Contrary to the traditional "Rule of Tens," as many as 25% of pheochromocytomas occur in hereditary tumor syndromes, such as multiple endocrine neoplasia-2, von Hippel-Lindau disease, neurofibromatosis-1, or hereditary or familial paraganglioma syndrome. Surgical resection remains the only curative therapy for pheochromocytomas, and advances in minimally invasive techniques have shown laparoscopic adrenalectomy to be safe and effective. Paragangliomas are extremely rare tumors, especially in children, and the role of laparoscopy in their treatment is evolving. This case report and the accompanying video demonstrate that the laparoscopic approach to retroperitoneal paraganglioma resection provides excellent exposure of the tumor and surrounding structures. Given proper patient preparation and perioperative monitoring, laparoscopic exploration and resection of paragangliomas can be safely and successfully accomplished in children. In addition, genetic analysis should be considered for all patients presenting with these tumors.

Pheochromocytoma in children and adolescents

Eleven subjects aged <20 yr with histologically proven pheochromocytoma between 1987 and 2006 were analyzed. Family history was present in 18%. In 2 patients, pheochromocytoma was part of VHL and in one it was associated with MEN 2. Twenty four hour urine VMA level was elevated in 100% and metanephrine level in 73%. CT/ MRI were showing the tumor in all. Prazosin extended release tablets (maximum 30 mg/day) were used in 73% and doxazosin (maximum 12 mg/ day) in 27%. Intraoperative BP fluctuations were seen in 27%. All were biochemically cured after surgery. Preoperative á blockade with extended release prazosin and doxazosin were effective in controlling perioperative BP fluctuations. Hence these drugs can be used in children and adolescents without fear of postoperative hypotension.

Spontaneous pathology of the baboon endocrine system

BACKGROUND

Study of endocrine pathology in animal models is critical to understanding endocrine pathology in humans.

METHODS

We evaluated 434 endocrine-related diagnoses from 4619 baboon necropsies, established the incidence of spontaneous endocrine pathology, and analyzed the clinical and biochemical data associated with the individual cases.

RESULTS

The most common diagnoses in descending order, were pancreatic islet cell amyloidosis (n = 259), ovarian cysts (n = 50), pituitary adenoma (n = 37), pancreatic islet cell adenoma (n = 20), granulosa cell tumor (n = 15), thyroid adenoma (n = 11), adrenal hyperplasia (n = 10), thyroid carcinoma (n = 8), and pheochromocytoma (n = 6). The incidence of pancreatic islet cell amyloidosis progressively increased with age. Pheochromocytomas were associated with renal and heart failure. The incidence of pancreatic islet cell amyloidosis and adrenal pathology was similar to humans; the incidence of pituitary adenoma and thyroid pathology was lower than in humans.

CONCLUSIONS

Endocrine disease in baboons is common and shares clinical and biochemical characteristics with endocrine disease in humans.

Enhanced dense core granule function and adrenal hypersecretion in a mouse model of Rett syndrome

Rett syndrome (RTT) is a progressive developmental disorder resulting from loss-of-function mutations in the gene encoding methyl-CpG-binding protein 2 (MeCP2), a transcription regulatory protein. The RTT phenotype is complex and includes severe cardiorespiratory abnormalities, dysautonomia and behavioral symptoms of elevated stress. These findings have been attributed to an apparent hyperactivity of the sympathetic nervous system due to defects in brainstem development; however, the possibility that the peripheral sympathoadrenal axis itself is abnormal has not been explored. The present study demonstrates that the adrenal medulla and sympathetic ganglia of Mecp2 null mice exhibit markedly reduced catecholamine content compared with wild-type controls. Despite this, null animals exhibit significantly higher plasma epinephrine levels, suggesting enhanced secretory granule function in adrenal chromaffin cells. Indeed, we find that Mecp2 null chromaffin cells exhibit a cell autonomous hypersecretory phenotype characterized by significant increases in the speed and size of individual secretory granule fusion events in response to electrical stimulation. These findings appear to indicate accelerated formation and enhanced dilation of the secretory granule fusion pore, resulting in elevated catecholamine release. Our data therefore highlight abnormal catecholamine function in the sympathoadrenal axis as a potential source of autonomic dysfunction in RTT. These findings may help to explain the apparent 'overactivity' of the sympathetic nervous system reported in patients with RTT.

Survival of patients with metastatic malignant pheochromocytoma and efficacy of combined cyclophosphamide, vincristine, and dacarbazine chemotherapy

CONTEXT

About 10% of pheochromocytomas are malignant. Exact survival has not been reported, nor has an analysis of the efficacy of chemotherapy on survival time.

OBJECTIVE

The aim of this study was to analyze the survival curves and survival times of patients with malignant pheochromocytoma and to determine the efficacy of chemotherapy on prolongation of life.

DESIGN

An inception cohort and Kaplan-Meier survival analysis was conducted.

PATIENTS AND OUTCOME MEASURES

Thirty-two patients with metastasized malignant pheochromocytoma were analyzed for survival. Twenty-five patients had undergone excision of their primary tumors. Survival curves were compared among the 16 patients in this group treated with combined chemotherapy using cyclophosphamide, vincristine and dacarbazine (CVD) and the nine patients not treated with chemotherapy.

RESULTS

The survival curve of the 32 patients declined continuously and linearly to at least 20 yr after the diagnosis of pheochromocytoma. The 50% survival rate was estimated to be 14.7 yr. In the 25 patients whose primary tumor was excised, patients who already had metastases at the time of pheochromocytoma diagnosis had better survival than those whose metastases were found later. The survival rate after diagnosis of metastasis was worse in the CVD group than in controls. When the effects of CVD were examined after stratifying several factors, female gender and adrenal origin of tumor were found to be negative prognostic factors for CVD chemotherapy.

CONCLUSION

The present study revealed a long survival time. CVD chemotherapy was not shown to extend survival, especially for women and patients with adrenal gland-derived primary tumors.

Was a hypertensive crisis in a patient with pheochromocytoma caused by rocuronium?: A case report

Pheochromocytoma is an uncommon tumor that originates in the adrenal medulla or in other paraganglia of the sympathetic nervous system. If a hypertensive crisis occurs during general anesthesia in incidental or untreated pheochromocytoma, it is a life-threatening event with a mortality rate of about 80%. Anesthetic drugs such as pancuronium, atracurium, and metoclopromide can exacerbate the potentially lethal cardiovascular effects of catecholamines. We report a case of a patient with pheochromocytoma who display abrupt increases in systolic arterial pressure and plasma norepinephrine following rocuronium administration. This case indicates the possible involvement of elevated sympathetic nervous system to a catecholamine crisis triggered by rocuronium in pheochromocytoma.

Update on pediatric pheochromocytoma

Pheochromocytomas are rare tumors in children arising from chromaffin cells of adrenal medullary or extra-adrenal paraganglionic tissue. The tumors are characterized by synthesis, metabolism, and secretion of catecholamines. The formerly used guidelines for pheochromocytoma have been changed by recent discoveries, implementation of new approaches, and understanding of biochemistry, genetics, imaging, pathophysiology, and nomenclature of these tumors. In children, pheochromocytomas are more frequently familial, extra-adrenal, bilateral, and multifocal than in adults. Because of a highly variable clinical presentation, pheochromocytoma is often referred to as the great mimic. Measurements of plasma or urinary fractionated metanephrines are recommended as first-line biochemical tests for diagnosis, with optimum diagnostic sensitivity to be preferred over specificity. In general, localization studies must be used secondary to clinical and biochemical evidence. Adequate preoperative treatment with alpha-blockade is mandatory, including for pheochromocytomas that do not secrete but only synthesize catecholamines. Because approximately 40% of pheochromocytomas in children have a hereditary basis, proper genetic testing should be performed, with appropriate implications for future follow-up and treatment options. The risk for development of malignant disease depends highly on the underlying mutation, which may also impact recommendations concerning screening and surgical or systemic treatment. This article reviews recent advances in biochemistry, genetics, and imaging and outlines recommendations for improved evaluation and treatment of children with benign or malignant pheochromocytomas.

Management of adrenal incidentaloma

Clinically inapparent adrenal masses, or adrenal incidentalomas, are discovered inadvertently in the course of work-up or treatment of unrelated disorders. Cortical adenoma is the most frequent tumour detected incidentally, but adrenocortical cancer, phaeochromocytoma and metastasis are not rare. Two critical questions should be answered before trying to outline the management of adrenal incidentaloma: (1) which tumours may cause harm to the patient, and (2) can we recognize and effectively treat such tumours? Based on the available scientific evidence, two major recommendations should be made: (1) identify either primary (adrenocortical cancer) or secondary (adrenal metastasis) malignancy; (2) identify phaeochromocytoma. Radiological evaluation is the key to the differential diagnosis of benign and malignant tumours. Endocrine testing is necessary to exclude phaeochromocytoma in all patients with an adrenal incidentaloma because this tumour may remain undiagnosed after imaging studies. The management of clinically inapparent adrenal adenomas may vary depending whether or not they are functioning. It is reasonable to screen for primary aldosteronism all hypertensive patients and recommend adrenalectomy when an aldosterone-producing adenoma is confirmed. A subset of adenomas secretes cortisol autonomously and may lead to mild hypercortisolism, a condition defined as subclinical Cushing's syndrome. The criteria for defining subclinical Cushing's syndrome are controversial, and we currently do not have sufficient evidence to define a gold standard for screening. Also the management of this condition is largely empirical, and data are insufficient to indicate the superiority of a surgical or non-surgical approach to managing patients with subclinical Cushing's syndrome.

Degree of catecholamine hypersecretion is the most important determinant of intra-operative hemodynamic outcomes in pheochromocytoma

Pheochromocytoma resection is often complicated by intra-operative hypertension and post-resection hypotension. Factors associated with these hemodynamic alterations are not well defined. The aim of this study was to analyse the clinical-laboratory features associated with hemodynamic parameters during pheochromocytoma resection. Twenty-seven patients submitted to tumor resection - either open (no.=18) or video laparoscopic - between 1978-2007 were included. Nineteen received pre-operative alpha-blockers. Intra-operative hemodynamic data analysed were: maximum and minimum mean arterial blood pressure (MABP), no. of severe hypertensive (systolic BP >200 mmHg) and hypotensive episodes (MABP <60 mmHg), maximum and minimum heart rate (HR), no. of episodes of tachycardia and bradycardia, need to receive iv intra-operative treatment for hypertension and hypotension and the volume of fluids administered during surgery. Patients were 39.4+/-14.4-yr-old, 66% women. Intra-operative hemodynamic parameters were not different in patients submitted to open or video laparoscopic resection. Maximum intraoperative HR and the percentage of patients with HR>100 beats/min were higher in patients without pre-operative alpha- blocker treatment (no.=8). Pre-operative urinary vanylmandelic acid was positively associated with intra-operative maximum MABP (r=0.535, p=0.047) and with maximum transoperative systolic BP (r=0.805, p=0.016). Pre-operative urinary catecholamine (Pearson correlation r=0.575, p=0.03) and vanylmandelic acid (Pearson correlation r=0.605, p=0.04) levels were associated with maximum intra- operative MABP, adjusted for the presence of pheochromocytoma symptoms, surgical approach and pre-operative alpha-blockers. In conclusion, the degree of pre-operative catecholamine secretion was the most important aspect of transoperative BP control.

Pheochromocytoma-induced cardiomyopathy is modulated by the synergistic effects of cell-secreted factors

BACKGROUND

Pheochromocytomas are rare tumors derived from the chromaffin cells of the adrenal medulla. Although these tumors have long been postulated to induce hypertension and cardiomyopathy through the hypersecretion of catecholamines, catecholamines alone may not fully explain the profound myocardial remodeling induced by these tumors. We sought to determine whether changes in myocardial function in pheochromocytoma-induced cardiomyopathy result solely from catecholamines secretion or from multiple pheochromocytoma-derived factors.

METHODS AND RESULTS

Isolated cardiomyocytes incubated with pheochromocytoma-conditioned growth media contracted at a higher frequency than cardiomyocytes incubated with norepinephrine (NE) only. Sprague-Dawley rats and black-6 mice were implanted with agarose-encapsulated pheochromocytoma (PC12) cells, dihydroxyphenylalanine decarboxylase knock-out PC12 cells deficient in NE (PC12-KO), or NE-secreting pumps. PC12 cell implantation increased left ventricular dilation by 35+/-6% and 9.6+/-1.4% and reduced left ventricular fractional shortening by 20+/-3% and 28+/-4% in rats and mice compared with animals dosed only with NE, respectively. Elimination of NE secretion in PC12-KO cells induced neither cardiac dilation (3.9%+/-1.8% increase versus control) nor changes in (1.9%+/-0.4% reduction) fractional shortening compared to controls.

CONCLUSIONS

Pheochromocytomas induce a greater degree of cardiomyopathy than equivalent doses of NE, suggesting pheochromocytoma-induced cardiomyopathy is not solely mediated by NE, rather pheochromocytoma secretory factors in combination with catecholamines act synergistically to induce greater cardiac damage than catecholamines alone.

Improvement in renal dysfunction and symptoms after laparoscopic adrenalectomy in a patient with pheochromocytoma complicated by renal dysfunction

A 70-year-old patient who was undergoing treatment for diabetes mellitus and chronic hepatitis was admitted to our hospital for evaluation of a tumor in the left adrenal gland (50 x 45 mm) and renal failure. On the basis of the patient's increased serum concentrations of catecholamines and other metabolites and the results of positron emission tomography (PET), the patient was diagnosed with a pheochromocytoma; iodinated metaiodobenzylguanidine ([(131)I]MIBG) scintigraphy was insufficient to establish this diagnosis. Subsequently, he underwent surgery for tumor resection. Histological examination suggested the tumor to be a malignant pheochromocytoma. After left adrenalectomy was performed, the elevated catecholamine and metabolite concentrations and the blood pressure were restored to normal, and the patient's symptoms of severe headaches and vertigo reduced. Furthermore, his renal function improved (Cr 2.0-1.2 mg/dl). Our patient exhibited a rare condition of pheochromocytoma complicated by renal failure, which was successfully treated with laparoscopic surgery.

[Biological diagnosis of pheochromocytomas and paragangliomas]

Pheochromocytomas and/or paragangliomas are rare, heterogeneous tumors of the chromaffin cells. Thirty percent of the patients presented with these diseases in a hereditary context. The biological diagnosis relies on the identification of excessive secretion of the metanephrines which are more sensitive and specific than those of catecholamines The published recommendations give the opportunity to choose between the free metanephrines and the fractionated metanephrines in sera or urines. The concentrations of the free plasmatic metanephrines reflect the ongoing production of tumor. They are little sensitive to the renal failure. The assay of the vanillylmandelic acid should be dropped because of its inefficiency. The assay of the chromogranin A in serum should be used in association with those of metanephrines in the diagnosis but also in the follow-up. Its role still has to be precised.

Encapsulated pheochromocytoma cells secrete potent noncatecholamine factors

Pheochromocytomas are widely believed to induce cardiomyopathy via hypersecretion of catecholamines, including norepinephrine (NE). NE can have direct cardiomyocyte toxicity and/or can stimulate myocardial remodeling secondary to the induction of hypertension. Yet, the development of cardiomyopathy is not entirely related to catecholamine dose or the extent of hypertension. To explore these effects, we engineered a polymeric encapsulation system to control PC12 cell kinetics and NE release in vitro and in vivo. Primary neonatal rat cardiomyocytes incubated with pheochromocytoma-conditioned media exhibited greater cytoskeletal changes than myocytes cultured with identical doses of NE alone, including more profound dose-dependent decreases in desmin, beta-tubulin, and vinculin and upregulation of dystrophin. Cardiomyocyte contractility was 29 +/- 6% greater at given levels of NE release. Agarose-encapsulated PC12 cells retain cell viability and structural integrity in vivo. These implants induce a 30% greater degree of cardiac enlargement as compared to pumps releasing equivalent doses of NE. Protein level alterations observed in vitro were mirrored in vivo after implantation of encapsulated cells or NE pumps for 28 days. Together, these data suggest that pheochromocytoma-induced cardiomyopathy is not solely a catecholamine-mediated event; rather, the pathogenesis of this dilated cardiomyopathy appears to be dependent upon secondary factors unexamined to date.

A clinical overview of pheochromocytomas/paragangliomas and carcinoid tumors

Pheochromocytomas/paragangliomas are rare tumors; most are sporadic. Biochemical proof of disease is better with measurement of plasma metanephrines and less cumbersome than determinations in urine; its implementation is expanding. Anatomical imaging with computed tomography or magnetic resonance imaging should be followed by functional (nuclear medicine) imaging: chromaffin tumor-specific methods are preferred. Treatment is surgical; for nonoperable disease other options are available. Overall 5-year survival is 50%. Carcinoid tumors derive from serotonin-producing enterochromaffin cells in the fore-, mid- or hindgut. Biochemical screening (and follow-up) is done with measurements of 5-hydroxyindoloacetic acid in urine. For most carcinoids, functional imaging is better than other modalities in localizing primary tumors. Surgery is the treatment of choice; nonresectable tumors are treated with somatostatin analogs or chemotherapy. Overall 5-year survival for patients with carcinoids is 67%.

Diagnosis and treatment of pheochromocytoma in an academic hospital from 1997 to 2007

BACKGROUND

The diagnosis and treatment of pheochromocytoma pose a challenge to physicians. Several trends in the presentation, diagnosis, and surgical treatment of pheochromocytoma have emerged in the last 10 years. The diagnostic accuracy and consequences of misdiagnosis of pheochromocytoma are not well known. We aimed to systemically study the diagnostic accuracy and treatment outcomes of pheochromocytoma and to reveal the causes and consequences of misdiagnosis (including both overdiagnosis and underdiagnosis).

METHODS

We reviewed the electronic and paper charts of 49 patients who underwent adrenalectomy or adrenal biopsy with either preoperative or pathologic diagnosis of pheochromocytoma in a large academic hospital from 1997 to 2007. Three groups of patients (overdiagnosed, correctly diagnosed, and underdiagnosed) were compared on clinical courses, biochemical tests, imaging studies, and surgical outcomes.

RESULTS

Pheochromocytoma was overdiagnosed in 9 patients, correctly diagnosed in 30 patients, and underdiagnosed in 10 patients. The overdiagnosis rate was 23% (9/39), and the underdiagnosis rate was 25% (10/40). The 3 distinct groups of patients exhibited significant differences in clinical presentation, biochemical tests, and imaging characteristics. The most common causes of overdiagnosis were misinterpretation of borderline biochemical test results and overzealous imaging. Overdiagnosis subjected patients to unnecessary adrenalectomy and its complications. The most common cause of underdiagnosis was failure to consider and test for pheochromocytoma. Underdiagnosis resulted in dangerous adrenal biopsy or adrenalectomy with hypertensive crisis and nearly doubled the length of stay in hospital. Surgical resection of correctly diagnosed pheochromocytoma was largely effective and safe, but intraoperative and postoperative complications occurred in some patients.

CONCLUSION

We conclude that misdiagnosis of pheochromocytoma is not uncommon and causes serious adverse effects. Correct interpretation of biochemical tests and imaging is crucial to a correct diagnosis, and pheochromocytoma should always be included in the differential diagnosis of any adrenal mass. Our data suggest that physician education is needed to improve the diagnosis and treatment of pheochromocytoma.

An unusual association: pheochromocytoma on an atrophied adrenal gland due to addison's disease

Autoimmune polyendocrine syndrome type II (APS-II) is the most common immunoendocrinopathy syndrome. APS-II is defined by the development of two or more of the following entities: primary adrenal insufficiency (Addison's disease), Graves' disease, type 1A diabetes mellitus, autoimmune thyroiditis, primary hypogonadism, celiac disease, and myasthenia gravis. Other frequent clinical findings are vitiligo, alopecia, pernicious anemia and/or serositis. Primary adrenal insufficiency in these patients affects the adrenal cortex, which is destroyed by autoantibodies against 21-hydroxylase. Unlike other causes of adrenal insufficiency (infectious diseases, infiltrative diseases, bleeding, tumors), the adrenal medulla is not involved. Pheochromocytomas are tumors arising from the chromaffin cells of the sympathetic nervous system in the adrenal medulla. The clinical symptoms of these tumors vary from isolated hypertension or hypertension accompanied by paroxysmal episodes -including the classical triad of headache, palpitations and diaphoresis-to potentially serious manifestations such as acute pulmonary edema, arrhythmias and sudden death. Nevertheless, up to 40% of affected patients are asymptomatic. We present the case of a patient diagnosed with APS-II who developed a pheochromocytoma. In this patient, the adrenal gland cortex was atrophied and the tumor was attached to the adrenal medulla. This coexistence of endocrinopathies, with no etiologic connection, is a surprising finding, which has not previously been described in the current literature.

Pheochromocytoma: diagnostic and therapeutic update

Pheochromocytomas are catecholamine-secreting tumors that arise from chromaffin cells of the sympathetic nervous system. In 80-85% of cases, these tumors are located in the adrenal medulla while the remainder is located in extra-adrenal chromaffin tissues (paragangliomas). Pheochromocytomas account for 6.5% of incidentally discovered adrenal tumors. These tumors may be sporadic or the result of several genetic diseases: multiple endocrine neoplasia type 2, von Hippel-Lindau syndrome, neurofibromatosis type 1, and familial paraganglioma associated with mutations in succinate dehydrogenase subunits. Diagnosis of pheochromocytoma should first be established biochemically by measuring plasma free metanephrines and urinary fractionated metanephrines. The radiological imaging tests of choice are computed tomography (CT) or magnetic resonance imaging (MRI). The first-line specific functional imaging test is scintigraphy with (123)I-metaiodobenzylguanidine (MIBG); if this test is unavailable, scintigraphy with (131)I-MIBG is the second choice. Positron emission tomography (PET) with (18)F-F-fluorodopamine (F-DA) is useful in metastatic disease. The treatment of choice is laparoscopic surgery after adequate alpha adrenergic blockade. Approximately 10% of tumors are malignant. Chemotherapy is used for inoperable disease. Prognosis is good except in malignant disease, in which 5-year survival is less than 50%. The identification of the genes causing hereditary pheochromocytoma has led to changes in the recommendation for genetic testing.

Treatment of malignant pheochromocytoma/paraganglioma with cyclophosphamide, vincristine, and dacarbazine: recommendation from a 22-year follow-up of 18 patients

BACKGROUND

A long-term follow-up was conducted of 18 patients with a diagnosis of pheochromocytoma/paraganglioma treated with a combination of cyclophosphamide, vincristine, and dacarbazine (CVD).

METHODS

The study design was a nonrandomized, single-arm trial conducted at a government medical referral center. Eighteen patients with metastatic malignant pheochromocytoma/paraganglioma were studied. After controlling symptoms of catecholamine excess, patients were treated with cyclophosphamide at 750 mg/m(2), vincristine at 1.4 mg/m(2), and dacarbazine at 600 mg/m(2) on Day 1 and dacarbazine at 600 mg/m(2) on Day 2, every 21 to 28 days.

RESULTS

Combination chemotherapy with CVD produced a complete response rate of 11% and a partial response rate of 44%. Median survival from a landmark was 3.8 years for patients whose tumors responded to therapy and 1.8 years for patients whose tumors did not respond (P = .65). All patients with tumors scored as responding reported improvement in their symptoms related to excessive catecholamine release and had objective improvements in blood pressure. CVD was well tolerated with only grade I/II toxicities.

CONCLUSIONS

Combination chemotherapy with CVD produced objective tumor responses in patients with advanced malignant pheochromocytoma/paraganglioma. In this 22-year follow-up there was no difference in overall survival between patients whose tumors objectively shrank and those with stable or progressive disease. However, patients reported improvement in symptoms, had objective improvements in blood pressure, and had tumor shrinkage that made surgical resection possible. The authors conclude that CVD therapy is not indicated in every patient with metastatic pheochromocytoma/paraganglioma, but should be considered in the management of patients with symptoms and where tumor shrinkage might be beneficial.

Clinical Use of Laboratory Tests for the Identification of Secondary Forms of Arterial Hypertension

The prevalence of secondary hypertension can be underestimated if appropriate tests are not performed. The importance of selecting patients with a high pre-test probability of secondary forms of hypertension is first discussed. The laboratory tests currently used for seeking a cause of hypertension are critically reviewed, with emphasis on their operative features and limitations. Strategies to identify primary aldosteronism, the most frequent form of secondary hypertension, and to determine its unilateral or bilateral causes are described. Treatment entails adrenalectomy in unilateral forms, and mineralocorticoid receptor blockade in bilateral forms. Renovascular hypertension is also a common, curable form of hypertension, that should be identified as early as possible to avoid the onset of cardiovascular target organ damage. The tests for its confirmation or exclusion are discussed. The various tests available for the diagnosis of pheochromocytoma, which is much rarer than the above but extremely important to identify, are also described, with emphasis on recent developments in genetic testing. Finally, the tests for diagnosing some rarer monogenic forms and other renal and endocrine causes of arterial hypertension are explored.

Safety of laparoscopic adrenalectomy in patients with large pheochromocytomas: a single institution review

BACKGROUND

Laparoscopic adrenalectomy is the procedure of choice for small adrenal tumors, but some concerns have been voiced when this approach is adopted for larger tumors and pheochromocytomas. The aim of this study was to examine the results of the laparoscopic resection of large pheochromocytomas.

METHODS

A retrospective review of adrenalectomies performed for adrenal pheochromocytomas>6 cm in diameter. We compiled and analyzed the early operative complications, histologic findings, and cure rates with a minimum of 1 year of follow-up after surgery.

RESULTS

From 1996 to 2005, a total of 445 laparoscopic adrenalectomies were performed in our institution using the anterolateral transperitoneal approach. From this series we identified 18 procedures for pheochromocytomas with an average diameter on imaging of 78.2 mm (range 60-130 mm). All patients were rendered safe with a standard departmental protocol involving calcium-channel blockade initiated at least 2 weeks prior to surgery. The average peak intraoperative blood pressure was 187 mmHg. Capsular disruption occurred in two cases. One patient required an intraoperative blood transfusion due to intraoperative blood loss. No immediate conversions to an open procedure were required, but one patient underwent a delayed laparotomy for hematoma formation. Histologically, four of the adrenal tumors displayed evidence of vascular invasion. Biochemical cure was achieved in all patients after a median follow-up of 58 months (16-122 months).

CONCLUSIONS

Laparoscopic adrenalectomy appears to be a safe and effective approach for large pheochromocytomas when no preoperative or intraoperative evidence of local invasion is present.

A sporadic case of paraganglioma undetected by urine metabolite screening

Phaeochromocytoma is a rare cause of hypertension in children, but important to be recognised, as hypertension can be severe and surgery is often curative. Here, we report on a 7-year-old boy with a phaeochromocytoma, who had normal levels of commonly assayed catecholamine metabolites in the urine. Postoperatively, the patient developed renal vein thrombosis. Appropriate screening tests for phaeochromocytomas, peri-operative management, and the high incidence of an underlying genetic basis, even in sporadic cases, are discussed.

Imaging of hyperfunctioning adrenal masses

Adrenal imaging not only aims to detect hyperfunctioning adrenal lesions responsible for distinct clinical syndromes (pheochromocytoma, Cushing's syndrome or primary aldosteronism) but also to differentiate malignant from benign disease. Computed tomography (CT), MRI and high-resolution ultrasound imaging methods are available for detection of adrenal masses with high sensitivities. Although the risk of malignancy increases with the size of the adrenal mass, this criterion does not discriminate malignant from benign disease with sufficient specificity. Attenuation values on unenhanced CT, contrast washout characteristics on CT and chemical-shift imaging on MRI help differentiate adrenal adenomas and nonadenomas. Adrenal lesions with equivocal results on CT and MRI can be characterized further by functional nuclear medicine imaging. Radiopharmaceutical agents specifically detect masses derived from the adrenal cortex (e.g.,¹³¹I-6-iodomethyl-norcholesterol) and from the adrenal medulla (e.g., ¹²³I- and ¹³¹I-meta-iodobenzylguanidine). Unspecific tracers, such as ¹⁸F-fluorodeoxyglucose, are very useful in discriminating malignant and benign adrenal tumors.

Gender-related differences in the clinical presentation of malignant and benign pheochromocytoma

Signs and symptoms associated with pheochromocytomas are predominantly caused by catecholamine excess, but tend to be highly variable and non-specific. In this study, we evaluated 23 male and 35 female pheochromocytoma patients for symptoms and signs of pheochromocytoma with special regard to gender-related differences in presentation. Total symptom score comparison between genders showed significant differences (12.0 vs. 7.8, P-value 0.0001). Female patients reported significantly more headache (80% vs. 52%), dizziness (83% vs. 39%), anxiety (85% vs. 50%), tremor (64% vs. 33%), weight change (88% vs. 43%), numbness (57% vs. 24%), and changes in energy level (89% vs. 64%). Females and males displayed comparable biochemical phenotypes (60% and 65% noradrenergic phenotype, respectively). Use of alpha- and/or beta-blockade between males and females did not differ significantly. Subgroup analyses and multiple regression analysis revealed gender differences to be irrespective of benign or malignant disease, use of adrenoceptor-blockade, age and biochemical phenotype. We conclude female patients have significantly more self-reported pheochromocytoma signs and symptoms than male patients irrespective of biochemical phenotype and tumor presentation which may be related to distinct catecholamine receptor sensitivity. Clinicians should be aware of these complaints in female pheochromocytoma patients and offer adequate treatment if indicated.

Giant cystic malignant pheochromocytoma invading right hepatic lobe: report on two cases

CONTEXT

Cystic pheochromocytomas are uncommon neuroendocrine tumors that originate from the adrenal medulla. Differing from the more frequent solid pheochromocytomas, which produce catecholamines and present adrenergic syndrome, cystic pheochromocytomas may not produce these. Their symptoms are generally associated with an abdominal mass or even pain, particularly if the mass attains large dimensions. Similarly, radiological diagnosis may also be difficult. Right-side lesions may be confounded with cystic hepatic tumors or even retroperitoneal sarcomas with cystic areas, using radiological methods. Sometimes, there may be a preoperative diagnosis of malignancy. Invasion of organs in this region (i.e. liver or kidney), or even the presence of a large retroperitoneal mass (of uncertain origin) with which multiple organs are involved, may be indicative of malignant origin.

CASE REPORT

Two cases of giant cystic pheochromocytoma that invaded the right hepatic lobe are described. These presented as abdominal masses. Both cases were malignant. They were treated by radical right nephrectomy plus right hepatectomy.

The role of somatostatin analogues in the treatment of neuroendocrine tumours

Neuroendocrine tumours belong to a heterogeneous family of neoplasms, originating in endocrine glands (such as the pituitary, parathyroid or the neuroendocrine adrenal glands), in endocrine islets (within the thyroid or pancreas) as well as in endocrine cells dispersed between exocrine cells throughout the digestive or respiratory tracts. The clinical behaviour of neuroendocrine tumours is variable; they may be functioning or not functioning, ranging from well-differentiated slow growing neuroendocrine tumours to poorly differentiated neuroendocrine tumours, which are highly aggressive malignant tumours. The development of somatostatin analogues as important diagnostic and treatment tools have revolutionised the clinical management of patients with neuroendocrine tumours. However, although symptomatic relief and stabilisation of tumour growth for various periods of time are observed in many patients treated with somatostatin analogues, tumour regression is rare. Development of new somatostatin analogues and new drug combination therapies should further improve the clinical management of these patients.

Torsades de Pointes: a rare complication of an extra-adrenal pheochromocytoma

Pheochromocytoma is an infrequent secondary cause of arterial hypertension, often associated with paroxysmal headache, sweating, weight loss, and palpitations. Cardiovascular complications of pheochromocytoma include sudden death, heart failure due to toxic cardiomyopathy, and hypertensive encephalopathy. Here we report the case of a female with an acquired long-QT-syndrome as a rare complication of an extra-adrenal pheochromocytoma. Diagnosis was made after sotalol-induced Torsades de Pointes.