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

Combined laparoscopic and thoracoscopic excision of pheochromocytoma and functional paraganglioma

In this paper, we report an 11-year-old girl who underwent a combined laparoscopic adrenalectomy procedure and thoracoscopic excision of a paravertebral mass. To our knowledge, this is the first such report in the English literature.

Biochemical detection of phaeochromocytoma: why are we continuing to ignore the evidence?

Phaeochromocytomas are rare tumours that require consideration among large numbers of patients with hypertension. If not diagnosed, the excessive secretion of catecholamines by these tumours can cause considerable morbidity and mortality. With a wide clinical variability in presentation, diagnosis can be difficult and invariably requires the biochemical confirmation of excessive catecholamine production by the tumour. At the First International Symposium on Phaeochromocytoma in October 2005, a panel of experts recommended that initial biochemical testing for phaeochromocytoma should include measurements of plasma and urinary metadrenalines. The accumulated evidence clearly indicates that measurement of fractionated metadrenalines in urine or plasma provides superior diagnostic sensitivity over plasma or urine measurements of catecholamines and metabolites. The low prevalence of phaeochromocytoma and paraganglioma (PGL) emphasizes the need to use biochemical tests of the highest sensitivity. To achieve this, it is recommended that the initial biochemical testing for phaeochromocytoma and secreting PGL should always include the measurements of metadrenalines in plasma or urine or both.

A case of pheochromocytoma complicated with slowly progressive type 1 diabetes mellitus and chronic thyroiditis

This is a case report regarding a 45-year-old woman, who has been undergoing treatment for diabetes mellitus (DM) with chronic thyroiditis (euthyroid state). The patient was admitted to our hospital for the evaluation of a right adrenal tumor (50 x 45 mm) and episodic hypertension. She was diagnosed as having pheochromocytoma based on the increased catecholamine and metabolite concentrations and the result of iodine-131 metaiodobenzyl guanidine ((131)I-MIBG) scintigraphy. Subsequently, the right adrenal tumor was excised. Slowly, progressive type 1 DM (SPIDDM) was confirmed by seropositivity to anti-glutamic acid decarboxylase (1890 U/ml) and the clinical course. After right adrenalectomy, the elevated catecholamine and metabolite concentrations and blood pressure returned to normal, and the dosage of insulin injection was reduced. However, she still needed the insulin injection therapy to control her blood glucose level. This case exhibited an extremely rare combination of pheochromocytoma and SPIDDM with chronic thyroiditis. Although it is common for patients with pheochromocytoma to exhibit glucose intolerance, this case raises the suggestion that measuring the levels of the autoantibody for pancreatic islet cells should be considered if SPIDDM is suspected in a patient with pheochromocytoma.

Perioperative hypertension in phaeochromocytoma patients undergoing adrenalectomy

This study was designed to compare perioperative blood pressure (BP) management in hypertensive patients with phaeochromocytoma undergoing preoperative α-blockade and in patients with other suprarenal gland tumors. Perioperative hemodynamic data and immediate postoperative outcome in two groups undergoing adrenalectomy were compared. 483 medical charts from urologic patients with tumors were analyzed. In the hypertensive (n = 168) group, 20 patients with suprarenal gland tumors were identified (phaeochromocytoma n = 11, other tumors n = 9). Demographic data, intraoperative consumption of fentanyl and phentolamine, preoperative hospital stay and postoperative ICU stay were compared. Mean arterial pressure (MAP) was registered on the day before surgery, before anesthetic induction, during surgery, and upon admission in the intensive care unit (ICU). Although BP values did not differ significantly on the day before anesthesia, before induction and during operation, significantly more antihypertensive drugs were used for BP regulation in phaeochromocytoma patients versus the other tumor group. The phaeochromocytoma group required significantly more fentanyl during surgery (370±87 vs. 242±35 µg; p = 0.04). MAP upon ICU admission was significantly lower (85.1 vs. 97.4, p = 0.02) after adrenalectomy in phaeochromocytoma patients versus the other tumor group. The postoperative MAP decreased significantly in the phaeochromocytoma group (21.51 mmHg, p = 0.005), whereas significant differences according to preoperative values were not observed in the other tumor group (5.5 mmHg, p = 0.416). Prolonged preoperative hospital stay (24.6 vs. 10.0 days, p = 0.005) and ICU stay were registered in the phaeochromocytoma group. Pheochromocytoma patients had more pronounced perioperative BP oscillations, needed more antihypertensive drugs, analgesics and required prolonged hospital stay than patients with other adrenal tumors. Prolonged α-blockade may have contributed to these effects.

Preoperative management of the pheochromocytoma patient

Pheochromocytomas are rare neuroendocrine tumors with a highly variable clinical presentation, but they most commonly present as spells of headaches, sweating, palpitations, and hypertension. Patients with pheochromocytoma may develop complicated and potentially lethal cardiovascular and other complications, especially in the setting of diagnostic or interventional procedures (e.g. upon induction of anesthesia or during surgery). The serious and potentially lethal nature of such complications is due to the potent effect of paroxysmal release of catecholamines. Because this warrants prompt diagnosis and treatment, the physician should be aware of the clinical manifestations and complications of catecholamine excess and be able to provide proper preoperative management to minimize catecholamine-related pre-, intra-, and postoperative adverse events. The following clinical scenario and discussion aim to enhance the knowledge of the physician regarding the behavior of pheochromocytoma and to outline current approaches to comprehensive preoperative management of patients suffering from this tumor.

A patient with bilateral pheochromocytoma as part of a Von Hippel-Lindau (VHL) syndrome type 2C

Background

Von Hippel-Lindau (VHL) disease is an autosomal dominant inherited disease. It is relatively recent that type 2C was identified as a separate group solely presenting with pheochromocytomas. As an illustration, an interesting case is presented of a pregnant woman with refractory hypertension. It proved to be the first manifestation of bilateral pheochromocytomas. The family history may indicate the diagnosis, but only identification of a germ line mutation in the DNA of a patient will confirm carriership.

Case presentation

A 27 year pregnant patient with intra uterine growth retardation presented with hypertension and pre-eclampsia. Magnetic resonance imaging revealed bilateral adrenal pheochromocytoma. She underwent laparoscopic adrenelectomy and a missense mutation (Gly93Ser) in exon 1 of the VHL gene on chromosome 3 (p25 – p26) was shown in the patient, her father and her daughter confirming the diagnosis of VHL.

Conclusion

In almost all VHL families molecular genetic analysis of DNA will demonstrate an inherited mutation. Because of the involvement in several organs, periodic clinical evaluation should take place in a well coordinated, multidisciplinary setting. VHL disease can be classified into several subtypes. VHL type 2C patients present with pheochromocytomas without evidence of haemangioblastomas in the central nervous system and/or retina and a low risk of renal cell carcinoma. Therefore, in such families, periodic clinical screening can be focussed on pheochromocytomas.

Feocromocitoma: uma causa rara de hipertensão arterial na infância

OBJETIVO: Relatar o caso de um adolescente com feocromocitoma, uma causa rara de hipertensão arterial na infância. DESCRIÇÃO: Adolescente internado em unidade de terapia intensiva infantil em decorrência de emergência hipertensiva, conseqüente à presença de feocromocitoma em adrenal esquerda, diagnosticado por meio de tomografia computadorizada do abdome e pela dosagem de adrenalina e noradrenalina urinárias. O paciente foi submetido à adrenalectomia esquerda, após o uso de alfa-bloqueador para controle do quadro hipertensivo. O anatomopatológico confirmou o diagnóstico do tumor. No pós-operatório, o paciente permaneceu estável, possibilitando a suspensão dos anti-hipertensivos. COMENTÁRIOS: Os feocromocitomas são tumores capazes de produzir catecolaminas, especialmente adrenalina e/ou noradrenalina. Cerca de 85 a 95% dos tumores são únicos, benignos e encontrados na medula adrenal. O feocromocitoma é um tumor de incidência rara e apenas 10 a 20% ocorrem na infância, representando uma causa rara de hipertensão arterial. Esta última é um sinal freqüente na maioria das crianças (80%), podendo ser acompanhada por cefaléia e sudorese. A encefalopatia hipertensiva consiste em uma forma de apresentação excepcional da doença. O diagnóstico pode ser realizado, na maioria dos casos, pela tomografia de abdome e pela dosagem das catecolaminas e seus metabólitos produzidos pelo tumor. O tratamento de escolha consiste na ressecção completa do tumor após o preparo farmacológico do paciente com o uso de alfa-bloqueador. No pós-operatório, a maioria dos pacientes evolui com controle do quadro de hipertensão arterial.

Pheochromocytoma as a catecholamine producing tumor: implications for clinical practice

Pheochromocytomas are catecholamine-producing tumors presenting with various clinical symptoms, but mostly with headache, sweating, palpitations and hypertension. If not properly diagnosed, secretion of catecholamines may lead to fatal cardiovascular consequences. Biochemical testing for pheochromocytoma should be performed not only in symptomatic subjects or in subjects with adrenal incidentaloma but also in subjects with a genetic predisposition for pheochromocytoma (multiple endocrine neoplasia type 2, Von Hippel-Lindau (VHL) syndrome, neurofibromatosis type 1 (NF 1)and mutations of succinate dehydrogenase (SDH) genes). Once a pheochromocytoma is proven, computed tomography (CT), magnetic resonance imaging (MRI) and functional imaging with [(123)I]-MIBG may be used for tumor localization. Adequate medical pre-treatment is essential for successful operation which is performed in most cases by laparoscopy. After tumor removal, further follow-up is necessary due to possible recurrence. Although prognosis after tumor resection is excellent, a significant proportion of pheochromocytomas recur, some as metastases. Thus, appropriate follow-up is mandatory.

Is It a Pheochromocytoma?

The patient is a 44-year-old man with a 4-year history of intermittently elevated blood pressure (BP) controlled by diet and exercise. Three months before evaluation he described daily "spikes" of BP with sharp unilateral headaches. He was seen in the emergency department with a BP of 212/106 mm Hg and was started on hydrochlorothiazide 25 mg daily. He denied palpitations, diaphoretic episodes, pallor, and tremor. The patient did not want to take medication and specifically requested an evaluation to rule out pheochromocytoma. Results from 24-hour urine tests for total metanephrines was 812 mg/24 h (normal, 130-520 mg/24 h), for total catecholamines was 53 mg/24 h (normal, 0-135 mg/24 h), and for vanillylmandelic acid was 4.7 mg/24 h (normal, <7 mg/24 h). Thyroid-stimulating hormone was 0.87 (normal, 0.4-4.0 IU/mL). Physical examination revealed normal optic fundi, negative cardiac examination results, and presence of peripheral pulses without bruits. His BP was now 136/74 mm Hg, with a heart rate of 76 beats per minute.

The MRI of extraadrenal pheochromocytoma in the abdominal cavity

The purpose of this study was to summarize the MR appearances of extraadrenal pheochromocytoma in the abdominal cavity and evaluate the capabilities of MRI in diagnosis of the tumor. Eleven consecutive patients with an extraadrenal pheochromocytoma in abdominal cavity who underwent preoperative 0.5 T (n=5) or 1.5 T (n=6) superconductor MRI and had a surgical resection were enrolled in the study. The MR scanning protocol included axial T(2)-weighted imaging with or without fat-suppressed sequences, axial and coronal uncontrast and contrast T(1)-weighted sequences with or without fat suppression. The extraadrenal pheochromocytomas were found in retroperitoneum (n=5), the urinary bladder (n=1), the pelvis (n=1), the right prerenal area (n=1), the renal hilus (n=1), the left paramusculus psoas major (n=1) and liver (n=1). The mean maximal diameter of tumors was 55.9 mm (range 17.8-162.2 mm). The high signal intensity was seen on T(2)-weighted imaging in all tumors compared to muscle or liver, especially with fat suppression. The intratumoral septa and capsules were shown in 63.6% and 72.7% of cases, respectively, which had low signal intensity on T(2)-weighted imaging. These relative characteristics may be helpful for qualitative diagnosis of extraadrenal pheochromocytomas with MRI. Other usefulness of MRI was to locate the position, to decide the range of tumors and to show well the relationship between the tumor and near structures.

Pheochromocytoma: recommendations for clinical practice from the First International Symposium. October 2005

The First International Symposium on Pheochromocytoma, held in October 2005, included discussions about developments concerning these rare catecholamine-producing tumors. Recommendations were made during the symposium for biochemical diagnosis, localization, genetics, and treatment. Measurement of plasma or urinary fractionated metanephrines, the most accurate screening approach, was recommended as the first-line test for diagnosis; reference intervals should favor sensitivity over specificity. Localization studies should only follow reasonable clinical evidence of a tumor. Preoperative pharmacologic blockade of circulatory responses to catecholamines is mandatory. Because approximately a quarter of tumors develop secondary to germ-line mutations in any one of five genes, mutation testing should be considered; however, it is not currently cost effective to test every gene in every patient. Consideration of tumor location, presence of multiple tumors, presence of metastases, and type of catecholamine produced is useful in deciding which genes to test. Inadequate methods to distinguish malignant from benign tumors and a lack of effective treatments for malignancy are important problems requiring further resolution.

Noradrenalin-secreting retroperitoneal schwannoma resected by hand-assisted laparoscopic surgery: report of a case

A 66-year-old woman was admitted to our hospital for investigation of a retroperitoneal mass. She was asymptomatic but her serum noradrenalin and vanillylmandellic acid levels were increased remarkably. Computed tomographic angiography showed a mass in the left side of the superior mesenteric artery (SMA) divergence, 6 x 4 cm in size, supplied mainly by the left adrenal artery. We performed hand-assisted laparoscopic surgery (HALS) using a Cavitron ultrasonic surgical aspirator. Abdominal exploration revealed that the tumor was located in the left side of the SMA root, but was not adhered to the adjacent organs. Her vital signs remained stable during the operation. Microscopic examination revealed a palisade formation, confirming a histopathological diagnosis of degenerated schwannoma (Antoni type B). Immunohistologically, the tumor cells were stained with S-100 protein and neuron-specific enolase. Her noradrenalin level normalized immediately after the operation and she remains in good health 3 years 2 months later.

Management and treatment of pheochromocytomas and paragangliomas

Pheochromocytomas and paragangliomas are rare neural crest-derived tumors of sympathetic (generally catecholamine producing) or parasympathetic (rarely catecholamine producing) origin. Patients affected by these tumors present with a variable clinical picture, often making diagnosis troublesome. Surgery is the treatment of choice, but requires appropriate medical management before, during, and after tumor resection. Appropriate follow-up of patients is particularly important to identify recurrences, remaining disease, or developing malignancy. Currently, however, no firm guidelines exist about what form follow-up should take. There is also a general lack of prospective studies establishing the best approaches for management and treatment of the tumor. Choice of the many available different therapeutic options instead usually depends on institutional experience and clinical setting, which may vary for different groups of patients. At the First International Symposium on Pheochromocytoma (ISP2005), held in Bethesda in October 2005, a panel of experts addressed and discussed the many therapeutic options and problems associated with management and treatment of patients with pheochromocytoma, reporting their personal experience and sharing their opinions with those of patient representatives. The aim of this special Discussion Session was to reconcile differences of opinion and reach agreement about appropriate management and therapeutic options. This article summarizes the discussion and the recommendations derived from that session.

Characteristics of pheochromocytoma in a 4- to 20-year-old population

Hypertension in children and adolescents has become a major health problem recently recognized, and in a significant number of patients it is due to an endocrine tumor. The aim of this study was to establish the characteristics of pheochromocytoma in a population of 58 patients between 4 and 20 years of age studied at our Center. They represented a 23% of the total population of 255 pheochromocytoma patients studied. In the younger group (under 20 years of age), there was a marked predominance of severe sustained hypertension (93%), only 7% presented paroxysmal hypertension and none of them was normotensive. The youngsters studied showed a higher incidence of bilateral adrenal pheochromocytoma (34%) and extra-adrenal pheochromocytoma (22%). Malignancy was found in 12% of these patients. In addition, the incidence of familial pheochromocytoma was elevated in these patients (39%). Surprisingly, in contrast with the adult population where the most frequent familial pheochromocytomas were multiple endocrine neoplasia (MEN) type 2A (15%), the younger population showed a higher predominance of von Hippel-Lindau (VHL) (28%) and lower incidence of MEN 2A, MEN 2B, neurofibromatosis (NF), and succinate dehydrogenase subunit B (SDHB). In the VHL group, only two patients belonging to one family, showed the R167W mutation, while the others showed novel mutations in conserved amino acids. It may be speculated that the high incidence of VHL in youngsters may account for the biochemical and clinical features they usually present.

Pheochromocytomas and secreting paragangliomas

Catecholamine-producing tumors may arise in the adrenal medulla (pheochromocytomas) or in extraadrenal chromaffin cells (secreting paragangliomas). Their prevalence is about 0.1% in patients with hypertension and 4% in patients with a fortuitously discovered adrenal mass. An increase in the production of catecholamines causes symptoms (mainly headaches, palpitations and excess sweating) and signs (mainly hypertension, weight loss and diabetes) reflecting the effects of epinephrine and norepinephrine on α- and β-adrenergic receptors. Catecholamine-producing tumors mimic paroxysmal conditions with hypertension and/or cardiac rhythm disorders, including panic attacks, in which sympathetic activation linked to anxiety reproduces the same signs and symptoms. These tumors may be sporadic or part of any of several genetic diseases: familial pheochromocytoma-paraganglioma syndromes, multiple endocrine neoplasia type 2, neurofibromatosis 1 and von Hippel-Lindau disease. Familial cases are diagnosed earlier and are more frequently bilateral and recurring than sporadic cases. The most specific and sensitive diagnostic test for the tumor is the determination of plasma or urinary metanephrines. The tumor can be located by computed tomography, magnetic resonance imaging and metaiodobenzylguanidine scintigraphy. Treatment requires resection of the tumor, generally by laparoscopic surgery. About 10% of tumors are malignant either at first operation or during follow-up, malignancy being diagnosed by the presence of lymph node, visceral or bone metastases. Recurrences and malignancy are more frequent in cases with large or extraadrenal tumors. Patients, especially those with familial or extraadrenal tumors, should be followed-up indefinitely.

Paragangliomes malins héréditaires : problèmes liés à la prise en charge des formes non sécrétantes

Non-functional paraganglioma have not clinical or biological characteristics, so that the diagnostic is most of the time delayed and made on the occasion of advanced abdominal tumor or symptomatic metastasis management. Hereditary forms, notably those with SDHB mutation, seem to have a poor prognosis. On the other hand, and on the oposite to sporadic forms, they are the only ones to benefit from genetic testing which make possible, if positive, an earlier diagnostic, before apparition of symptoms, recurrence or metastasis. We report a case of non-functional malignant hereditary paraganglioma diagnosed belatedly and we will consider management problems raised by non-functional forms.

Recent advances in the diagnosis and treatment of pheochromocytoma

Pheochromocytoma (PHEO) is considered to be a rare cause of hypertension. However, if left untreated, PHEOs may lead to fatal hypertensive crises during anesthesia and other stresses. The diagnosis of PHEO is therefore extremely important. A 24-hour blood pressure (BP) pattern per se might be of some diagnostic value due to frequently observed higher BP variability as well as an attenuated night-time BP decrease. So far, germline mutations in five genes have been identified to be responsible for familial PHEOs: the von Hippel-Lindau gene, which causes von Hippel-Lindau syndrome, the RET gene leading to multiple endocrine neoplasia type 2, the neurofibromatosis type 1 gene, which is associated with von Recklinghausen's disease and the genes encoding the B and D subunits of mitochondrial succinate dehydrogenase (SDHB, SDHD), which are associated with familial paragangliomas and PHEOs. Genetic analysis should be offered to those patients with confirmed PHEO who are 50 years old or younger. Plasma-free metanephrines or urinary fractionated metanephrines seem to have higher diagnostic values compared to plasma or urinary catecholamines for the biochemical diagnosis of PHEO. Imaging with (123)I-metaiodobenzylguanidine or (18)F-fluorodopamine PET, if available, are in addition to CT/MRI useful for the detection of multifocal/extra-adrenal forms. Appropriate pharmacologic treatment with subsequent laparoscopic extirpation of PHEO is usually successful in benign forms. There is, however, no convincingly effective mode of treatment in malignant PHEOs.

Pheochromocytoma: Physiopathologic Implications and Diagnostic Evaluation

Pheochromocytoma (PHEO) is a chromaffin cell tumor embryologically arising from the neural crest tissue. The dominant secretory products of PHEO are catecholamines: noradrenaline (norepinephrine), adrenaline (epinephrine), and to a lesser extent dopamine. In addition to catecholamines, PHEO cells also elaborate and release several neuropeptides and inflammatory cytokines which can exert intra-adrenal and extra-adrenal systemic effects and cause characteristic clinical syndromes. In a concise review we present the intra-adrenal and extra-adrenal pathophysiologic implications of PHEO and the nuclear medicine modalities that permit functional imaging of physiological processes and help localize these tumors. The specific pathways of synthesis, metabolism, and inactivation of catecholamines (of PHEOs and paragangliomas) can be used as means to develop suitable tracers for positron emission tomography (PET) ligands. In this review we focus on imaging with PET using [(18)F]-fluorodopamine, [(18)F]-fluorohydroxyphenylalanine, [(11)C]-epinephrine, or [(11)C]-hydroxyephedrine and examine how functional imaging can often complement traditional anatomical imaging modalities and other scintigraphic techniques.

MicroCT for high-resolution imaging of ectopic pheochromocytoma tumors in the liver of nude mice

Successful outcomes for patients with cancer often depend on the early detection of tumor and the prompt initiation of active therapy. Despite major advances in the treatment of many cancers, early-stage lesions often go undetected due to the suboptimal resolution of current anatomical and functional imaging modalities. This limitation also applies to preclinical animal tumor models that are crucial for the evaluation and development of new therapeutic approaches to cancer. We report a new mouse model of metastatic pheochromocytoma, generated using tail vein injection of the mouse pheochromocytoma cell (MPC) line that reproducibly generated multiple liver tumors in the animals. Furthermore, we show that in vivo microCT imaging enhanced using a hepatobiliary-specific contrast agent, glyceryl-2-oleyl-1,3-di-7-(3-amino-2,4,6-triiodophenyl)-heptanoate (DHOG), detected tumors as small as 0.35 mm as early as 4 weeks after the injection of the tumor cells. This model may be useful for in vivo studies of tumor biology and for development of new strategies to treat metastatic pheochromocytoma.

Effect of norepinephrine on RhoA, MAP kinase, proliferation and VEGF expression in human umbilical vein endothelial cells

Norepinephrine is a well known major vasoconstricting factor. Recent reports suggest that norepinephrine, in addition to acting as a vasoconstricting factor, may also play several additional roles in endothelial cells. These include: 1] induction of NO release. It has been demonstrated that a small GTP-binding protein, Rho, and its downstream effecter, Rho kinase (ROCK), negatively regulate endothelial nitric oxide synthase (eNOS) production. However, it is not known whether ROCK is directly involved in norepinephrine-induced NO release. 2] Norepinephrine is reported to induce a mitogenic effect, but whether MAPKs are involved in this process is unknown. 3] Recently, we demonstrated an increase in vascular endothelial growth factor (VEGF) mRNA/protein expression in human pheochromocytoma tissue in comparison to normal adrenomedullary tissue. Thus, it is reasonable to speculate that norepinephrine may stimulate the level of VEGF mRNA. The aim of the present study was to clarify the role of norepinephrine and related endothelial adrenoceptor systems in various pathophysiological conditions, such as hypertension and in particular pheochromocytoma, using human umbilical vein endothelial cells (HUVEC). Norepinephrine-induced RhoA attenuation, through cAMP/protein kinase A (PKA) activation coupled with beta-adrenoceptors, may lead to eNOS activation in acute conditions. Norepinephrine stimulates the production of VEGF mRNA through cAMP/PKA activation coupled with beta-adrenoceptors. Norepinephrine stimulates a mitogenic effect through ERK activation coupled with the alpha(1)-adrenoceptor. In conclusion, norepinephrine stimulates eNOS activity via RhoA attenuation, VEGF mRNA synthesis and mitogenic activity in endothelial cells. We propose that an excess of norepinephrine can lead to endothelial dysfunction due to these aforementioned processes.

Initial work-up and long-term follow-up in patients with phaeochromocytomas and paragangliomas

Catecholamine-producing tumours may arise in the adrenal medulla (phaeochromocytomas) or in extra-adrenal chromaffin cells (paragangliomas). The most specific and sensitive diagnostic test is the determination of plasma or urinary metanephrine levels. The tumour can be located by computed tomography, magnetic resonance imaging and metaiodo-benzylguanidine scintigraphy. Patients are treated by tumour resection. Phaeochromocytomas and paragangliomas may be sporadic or the result of several genetic diseases: multiple endocrine neoplasia type 2, neurofibromatosis 1, von Hippel-Lindau disease, succinate dehydrogenase-phaeochromocytoma-paraganglioma syndrome. Familial cases are diagnosed earlier and are more frequently bilateral and recurrent than sporadic cases. About 10% of tumours are malignant, either at initial surgery or during follow-up. Recurrences and malignancy are more frequent in cases with large or extra-adrenal tumours and in the succinate dehydrogenase subunit B-related phaeochromocytoma-paraganglioma syndrome. Patients should be followed up indefinitely, particularly if they have familial or extra-adrenal tumours.

The role of chromogranin A in the management of patients with phaeochromocytoma

OBJECTIVE

Chromogranin A (CgA) is the most accurate general marker of neuroendocrine tumours. Supranormal CgA concentrations have been recorded in patients with tumours of neuroectodermal origin such as phaeochromocytoma and paraganglioma.

DESIGN

The present study was performed to assess the role of CgA determination in the management of patients with phaeochromocytoma, in comparison with urinary catecholamines and their metabolites.

PATIENTS

The patients studied included 22 cases with phaeochromocytoma at initial presentation or at relapse some years after surgical cure or during follow-up of a malignant phaeochromocytoma. Seventeen patients were evaluated before and after surgical removal of phaeochromocytoma. To assess the specificity of the hormonal parameters, 20 subjects were enrolled as controls; they were from a group of patients referred to our observation for possible phaeochromocytoma and who were subsequently proven not to have the disease.

RESULTS

Urinary epinephrine and norepinephrine were supranormal in 82% and 77% of patients, respectively. Urinary metanephrines and normetanephrines were supranormal in 84% and 89% of patients, respectively. The combination of urinary metanephrine and normetanephrine had a sensitivity of 100% in identifying a phaeochromocytoma. CgA was supranormal in 91% of patients. Combining the results of CgA and urinary catecholamines (epinephrine and norepinephrine), the sensitivity for diagnosis of phaeochromocytoma was 100%. Urinary catecholamines, metabolites (metanephrine and normetanephrine) and CgA levels in patients with malignant phaeochromocytoma did not differ significantly from those of patients with benign lesions. In most cases, CgA normalized after surgery.

CONCLUSIONS

Our results indicate that CgA is a good marker of phaeochromocytoma; measurement of CgA could have a role in the follow-up of patients operated on for phaeochromocytoma.

Phaeochromocytomas presenting as acute crises after beta blockade therapy

OBJECTIVE

Phaeochromocytoma crisis is a life-threatening emergency that may be undiagnosed because of its numerous, nonspecific manifestations. We analysed, retrospectively, the presentation, management and outcome of patients who were admitted to our institution with phaeochromocytoma crises over a 5-year period.

RESULTS

Five patients (two males, three females; mean age 34.6 years, range 19-51 years) who presented as emergencies requiring intensive care, with multiple non-specific manifestations and previously undiagnosed pheochromocytoma, were identified. The initial presentation included features of cardiomyopathy (n = 3), atypical pneumonia with myocarditis (n = 1) and acute abdomen (n = 1). Only one of the five cases had a raised blood pressure at the time of the acute presentation. Initiation of beta blockers in four patients was associated with further deterioration in haemodynamic status, labile blood pressure and cardiac arrhythmias, which led to the diagnosis of the underlying phaeochromocytoma. Following intensive supportive therapy and alpha blockade, all five patients recovered and underwent elective surgical removal of phaeochromocytoma, uneventfully.

CONCLUSION

Unexplained cardiopulmonary dysfunction, particularly after the institution of beta blockers, should alert clinicians to the possibility of phaeochromocytoma. A high index of suspicion is essential to reduce morbidity and mortality in these patients through early diagnosis and aggressive management.

Lack of Symptoms in Patients with Histologic Evidence of Pheochromocytoma: A Diagnostic Challenge

Pheochromocytoma (Pheo) is a rare cause of hypertension (HTN). Classically, a triad of symptoms includes sweating, palpitations, and headache. HTN is often present and labile. Although a triad of symptoms is cited as the most frequent presenting complaints, our clinical experience leads us to question how often these are present. Thirty-two patients with histologically proven pheo or paraganglionoma were evaluated. Around 84.4% patients had adrenal pheos and 15.6% had extra-adrenal pheos. Two patients had bilateral adrenal tumors, two had a history of prior pheos, and four had a family history of pheo. There were 19 (59.4%) female and 13 (40.6%) male patients. Six (18.7%) patients were black and 26 (81.3%) were white. The mean age at presentation was 43.2+/-13.9 years. Two patients were known to have neurofibromatosis type 1, two had von Hippel-Lindau disease, one had multiple endocrine neoplasia 2A, and one PGL/SDHD genetic mutation. Twenty-six patients had sporadic tumors or had not had genetic testing. Biochemical diagnosis was confirmed with 24-h urine measurements. Urine catecholamine measurements were elevated at least 2 to 4 times above normal levels. Mean SBP readings at presentation were 128+/-19 mmHg. Mean DBP readings were 81+/-13 mmHg. Around 65.6% patients were hypertensive at presentation. Fifty percent of the patients had palpitations, 40.6% had tachycardia, 34.4% had sweating, and 31.3% had headaches. Initial presenting symptoms were diverse. Pheo is a rare clinical entity and remains a huge diagnostic challenge for all clinicians.

Genetic Testing in Pheochromocytoma: Increasing Importance for Clinical Decision Making

Hereditary pheochromocytomas and paragangliomas are caused by germline mutations in syndrome-associated genes. This includes multiple endocrine neoplasia Type 2 (MEN 2) caused by mutations in the RET proto-oncogene, von Hippel-Lindau (VHL) syndrome due to mutations of the VHL gene, neurofibromatosis Type I (NF1) caused by mutations of the NF1 gene, and pheochromocytoma/paraganglioma syndromes due to mutations in genes encoding the succinate dehydrogenase subunits D (SDHD) and B (SDHB). At the First International Symposium on Pheochromocytoma (ISP2005) organized by the National Institutes of Health, a panel of specialist clinicians and scientists from around the world addressed the topic of genetic testing in pheochromocytoma patients. This review summarizes the discussions and conclusions of the panel and provides a recommendation for evidence-based management of genetic testing in these patients and their families. A pragmatic algorithm is presented, taking into account patient age, tumor location (extra-adrenal, intra-adrenal, unilateral, and bilateral), biochemical presentation, and financial costs. This was based on cumulative frequencies ranging from 7.5% to 29% for germline mutations in four genes (RET, VHL, SDHB, and SDHD) in patients with apparently sporadic pheochromocytomas. This algorithm will need to be validated by further genetic analysis, multicenter studies, and long-term observations.

[Slight hormonal alterations in a patient with a large pheochromocytoma]

We present a case report that the patient had symptoms suggesting pheochromocytoma, a large tumor (> 50 g) and a single minimally altered laboratorial test, exemplifying a diagnostic pitfall. A 31 y.o. male patient had two acute abdominal events, the last one accompanied by headache, arterial hypertension, facial flushing, perspiration and cutaneous pallor. In another admission, the patient had sustained arterial hypertension and cardiac arrhythmia. From laboratory analysis, the vanililmandelic acid was slightly modified. Scintigraphy disclosed a large adrenal mass suggesting pheochromocytoma. Histopathology confirmed this hypothesis. This report points out that patients with symptoms suggesting pheochromocytoma, even when plasma catecholamines and urinary metanephrines levels are normal, may harbor large tumors with a high catecholamines turnover or that had undergone hemorrhagic necrosis.

Detecting pheochromocytoma: defining the most sensitive test

OBJECTIVE

To define the most sensitive biochemical test to establish the diagnosis of pheochromocytoma and also to assess the potential role of iodine 131-labeled metaiodobenzylguanidine scintigraphy (I-MIBG) in the diagnosis of this tumor.

SUMMARY BACKGROUND DATA

Pheochromocytoma is a rare, catecholamine-producing tumor with preferential localization in the adrenal gland. Despite its importance, the most sensitive test to establish the diagnosis remains to be defined.

METHODS

Prospective data collection was done on patients with pheochromocytoma treated at the Duke University Medical Center and the Durham Veterans Affairs Medical Center, Durham, NC. All urinary, plasma, and platelet analyses were highly standardized and supervised by one investigator (J.M.F.). I-MIBG scans were independently reviewed by 2 nuclear medicine physicians.

RESULTS

A total of 152 patients (55.3% female) were enrolled in the present analysis. Patients were predominantly white (73.7%). Spells (defined as profuse sweating, tachycardia, and headache) and hypertension at diagnosis were present in 51.4% and 66.6%, respectively. Bilateral disease was found in 12.5%, malignant pheochromocytoma in 29.6%, and hereditary forms in 23.0%. The most sensitive tests were total urinary normetanephrine (96.9%), platelet norepinephrine (93.8%), and I-MIBG scintigraphy (83.7%). In combination with I-MIBG scintigraphy, platelet norepinephrine had a sensitivity of 100%, plasma norepinephrine/MIBG of 97.1%, total urine normetanephrine/MIBG of 96.6%, and urine norepinephrine/MIBG of 95.3%.

CONCLUSIONS

The tests of choice to establish the diagnosis of pheochromocytoma are urinary normetanephrine and platelet norepinephrine. A combination of I-MIBG scintigraphy and diagnostic tests in urine, blood, or platelets does further improve the sensitivity. We thus advocate performing an MIBG scan if the diagnosis of pheochromocytoma is clinically suspected and catecholamine measurements are within the normal range.

Cirugía laparoscópica en el tratamiento de enfermedades adrenales: experiencia en 200 casos

OBJECTIVE

We report our experience in laparoscopic adrenalectomy, after adopting the laparoscopic technique for 10 years as a primary option for suprarenal surgery.

METHODS

We included 200 laparoscopic adrenal surgeries performed consecutively in 183 patients with surgical adrenal pathology between November 1994 and November 2005. Sixty-seven (36.6%) patients were male and 116 (63.4%) were female, with an average age of 49.1 years (age range 8 months to 78 years).

RESULTS

The most frequents clinical diagnosis were hyperaldosteronism (17.5%), metastatic cancer (15.8%), pheochromocytoma (15.3%), Cushing syndrome (7.1%), adrenal cyst (4.9%) and myelolipoma (2.7%). A total of 164 total adrenalectomies, 29 partial adrenalectomies and 7 marsupializations of adrenal cysts were performed. Mean surgical time was 82.6 minutes (range 25 to 240 minutes) and mean hospitalization time was 2.5 days (range 1-10 days). The size of the suprarenal gland and/or tumor varied between 1 and 14 cm (average 5.6 cm). The rate of complication was 6%. In 8 of the patients, there was another laparoscopic procedure besides the adrenal surgery: cholecystectomies (2), marsupialization of a renal cyst (2), block nephrectomy (2), partial nephrectomy for a tumor (1) and pancreatic cystectomy (1). One patient underwent a right laparoscopic adrenalectomy and an ipsilateral percutaneous nephrolithotomy.

CONCLUSION

The accumulated experience with 200 laparoscopic adrenal procedures has allowed the management of endocrine pathologies, such as, aldosteroma, pheochromocytoma, Cushing syndrome and rare entities, such as, cysts, myelolipomas in a suitable manner. Additionally, it has permitted us to extend the benefits of a minimally invasive procedure for large adrenal masses and selected oncology cases.

Genetic Testing in Pheochromocytoma or Functional Paraganglioma

Purpose

To assess the yield and the clinical value of systematic screening of susceptibility genes for patients with pheochromocytoma (pheo) or functional paraganglioma (pgl).

Patients and Methods

We studied 314 patients with a pheo or a functional pgl, including 56 patients having a family history and/or a syndromic presentation and 258 patients having an apparently sporadic presentation. Clinical data and blood samples were collected, and all five major pheo-pgl susceptibility genes (RET, VHL, SDHB, SDHD, and SDHC) were screened. Neurofibromatosis type 1 was diagnosed from phenotypic criteria.

Results

We have identified 86 patients (27.4%) with a hereditary tumor. Among the 56 patients with a family/syndromic presentation, 13 have had neurofibromatosis type 1, and germline mutations on the VHL, RET, SDHD, and SDHB genes were present in 16, 15, nine, and three patients, respectively. Among the 258 patients with an apparently sporadic presentation, 30 (11.6%) had a germline mutation (18 patients on SDHB, nine patients on VHL, two patients on SDHD, and one patient on RET). Mutation carriers were younger and more frequently had bilateral or extra-adrenal tumors. In patients with an SDHB mutation, the tumors were larger, more frequently extra-adrenal, and malignant.

Conclusion

Genetic testing oriented by family/sporadic presentation should be proposed to all patients with pheo or functional pgl. We suggest an algorithm that would allow the confirmation of suspected inherited disease as well as the diagnosis of unexpected inherited disease.

Phaeochromocytoma

Phaeochromocytomas are rare neuroendocrine tumours with a highly variable clinical presentation but most commonly presenting with episodes of headaches, sweating, palpitations, and hypertension. The serious and potentially lethal cardiovascular complications of these tumours are due to the potent effects of secreted catecholamines. Biochemical testing for phaeochromocytoma is indicated not only in symptomatic patients, but also in patients with adrenal incidentalomas or identified genetic predispositions (eg, multiple endocrine neoplasia type 2, von Hippel-Lindau syndrome, neurofibromatosis type 1, and mutations of the succinate dehydrogenase genes). Imaging techniques such as CT or MRI and functional ligands such as (123)I-MIBG are used to localise biochemically proven tumours. After the use of appropriate preoperative treatment to block the effects of secreted catecholamines, laparoscopic tumour removal is the preferred procedure. If removal of phaeochromocytoma is timely, prognosis is excellent. However, prognosis is poor in patients with metastases, which especially occur in patients with large, extra-adrenal tumours.

Adrenergic shock--an overlooked clinical entity?

We report a case of recurrent shock induced by pheochromocytoma in a previously healthy, normotensive patient. We review pathophysiology and clinical features of shock and cardiomyopathy in patients with pheochromocytoma. We discuss diagnostic evaluation and therapy for pheochromocytoma-induced shock.

Pheochromocytoma: current perspectives in the pathogenesis, diagnosis, and management

Pheochromocytomas (pheo) cause the most dramatic, life-threatening crises in all of endocrinology. A proper screening for pheo must be performed in any patient who has: 1) episodic headaches, tachycardia, and diaphoresis; 2) family history of pheo or multiple endocrine neoplasia; 3) incidental suprarenal mass; 4) paroxysms of tachyarrhythmias or hypertension; 5) adverse cardiovascular responses to anesthetic agents, histamine, phenothiazine, tricyclic antidepressants, etc); and 6) spells occurring during exercise, straining, etc. The key to diagnosing pheo is to suspect it, then to confirm it. Early recognition of its presence is critical to avoiding significant morbidity and mortality. Once suspected, the diagnosis can be confirmed with biochemical testing in virtually all patients. The combination of resting plasma catecholamines > or =2000 pg/mL and urinary metanephrines > or =1.8 mg/24 h has a diagnostic accuracy of 98% in both sporadic and hereditary pheos. When available, measurement of plasma free metanephrines should be performed especially in hereditary pheos. Provocative (glucagon) and suppression tests (clonidine) may be necessary when baseline measurements are inconclusive. CT and MRI are equally sensitive for localization (98% and 100%, respectively), but have lower specificities (70% and 67%). MIBG is 100% specific, but less sensitive (78%). The availability of various medical (selective alpha-1- and beta-adrenergic receptor antagonists, calcium channel blockers) and surgical modalities have made successful management more promising than ever before.

Recent developments in the therapy of phaeochromocytoma

The basic principles of treatment for phaeochromocytomas and paragangliomas are to block the effects of high catecholamines and make the patient safe for surgical removal of the tumour. The traditional preoperative medical preparation uses the non-selective alpha-adrenoceptor blocker phenoxybenzamine and a beta-adrenoceptor blocker, propranolol. Other agents have been used effectively, including selective alpha-adrenoceptor blockers, doxazosin and prazosin, and calcium channel antagonists. There have been no trial comparing regimens and there is some controversy as to the best regimen. Major advances have been made in laparoscopic and laparoscopic-assisted surgery. Cortical-sparing adrenalectomy has been used in some centres for familial phaeochromocytomas. High-dose [(131)I]-metaiodobenzylguanidine therapy and combined [(131)I]-metaiodobenzylguanidine and chemotherapy are promising new developments for the malignant disease. All patients should be followed indefinitely because the recurrence or malignancy rate is >or= 10% over a prolonged follow up.

Increased prevalence of catecholamine excess and phaeochromocytomas in a well-defined Dutch population with SDHD-linked head and neck paragangliomas

OBJECTIVE

The aim of this study was to identify the prevalence of catecholamine excess and phaeochromocytomas in a well-defined population of people with hereditary head and neck paragangliomas.

METHODS

We studied in a prospective follow-up protocol all consecutive patients referred to the Department of Endocrinology, Leiden University Medical Center, Leiden, The Netherlands with documented head and neck paragangliomas and either a positive family history for paragangliomas or a proven SDHD gene mutation. Initial analysis included medical history, physical examination and the measurement of excretion of catecholamines in two 24-h urine collections. In the case of documented catecholamine excess iodinated meta-iodobenzylguanidine (123I-MIBG) scintigraphy and magnetic resonance imaging were done.

RESULTS

Between 1988 and 2003, 40 consecutive patients (20 male and 20 female) with documented head and neck paragangliomas were screened. Biochemical screening revealed urinary catecholamine excess in 15 patients (37.5%). In nine of these 15 patients a lesion was found by 123I-MIBG scintigraphy. Exact localization by magnetic resonance imaging revealed phaeochromocytomas in seven of the 15 patients. One of the nine patients had an extra-adrenal paraganglioma. Histopathological examination in a subset of tumors displayed loss of heterozygosity of the wild-type SDHD allele in all cases.

CONCLUSIONS

The prevalence of catecholamine excess (37.5%) and phaeochromocytomas (20.0%) is high in patients with familial head and neck paragangliomas. Therefore, patients with hereditary head and neck paragangliomas require lifelong follow up by biochemical testing for catecholamine excess.

Extra-Adrenal Pheochromocytoma Presenting with Life-Threatening Ventricular Tachycardia: A Case Report

Extra-adrenal pheochromocytoma develops in paraganglion chromaffin cells of the sympathetic nervous system. It probably represents at least 15% of adult and 30% of childhood pheochromocytomas. Although electrocardiographic abnormalities occur in up to 75% of patients with pheochromocytoma, there are only three other reported cases of pheochromocytoma that initially presented with ventricular tachycardia. In this report, we describe a 64-year-old woman with an abdominal para-aortic extra-adrenal pheochromocytoma who presented with pulseless ventricular tachycardia and needed electrical defibrillation initially to keep vital signs. The 24-hour urine vanillylmandelic acid was 35.8 mg. Computerized tomography showed a left retroperitoneal mass. The postoperative course was uneventful. Pheochromocytoma was proved by histologic study.

Feocromocitoma

Apresentamos a experiência do Hospital das Clínicas da FMUSP, com o diagnóstico clínico, laboratorial e topográfico e com o tratamento do feocromocitoma. Embora novos testes bioquímicos, como as determinações de metanefrinas plasmáticas, tenham maior sensibilidade no diagnóstico desse tumor, testes mais disponíveis, como as determinações de metanefrinas urinárias e catecolaminas plasmáticas e urinárias ainda demonstram grande valor no diagnóstico. Eventuais falso-negativos e falso-positivos podem ser identificados com os testes de estímulo e depressão e com a exclusão do uso de droga. A ressonância magnética é o método mais sensível na identificação topográfica do tumor. O tratamento do tumor, exceto quando houver contraindicações, é sempre cirúgico e deve ser precedido pelo tratamento clínico. A identificação desse tumor é de fundamental importância no sentido de se prevenir a ocorrência de eventos com alta morbidade e mortalidade, bem como na identificação de outras síndromes neoplásicas que podem estar associadas a ele.