OBJECTIVE: Plasma free metanephrines (MNs) have been widely used as an initial test for pheochromocytoma and paraganglioma (PPGL). PPGL without MNs elevation has been reported on rare occasions. The objective of this study was to analyze the clinical profile of sporadic PPGL patients with normal MNs. METHODS: In the study, 104 patients with sporadic PPGL diagnosed by histopathology in Peking University First Hospital from March 2015 to January 2020 were enrolled. All the patients had plasma MNs result, of whom, eight (7.69%) were with normal MNs. The reasons for their medical visits, clinical manifestations, the levels of plasma free MNs, 3-methoxytyramine (3-MT), catecholamines and chromogranin A (CgA), and the imaging findings were documented. Their preoperative diagnosis, perioperative medical management, and intraoperative blood pressure were analyzed. All the data mentioned above were compared with the MNs elevated group. The postoperative follow-up for MNs normal patients were applied. RESULTS: For the eight PPGL patients with normal plasma MNs, the most common clinical symptoms were sweating (3/8), abdominal and back pain (3/8), headache (2/8), palpitations (2/8), and fatigue (2/8). There were no significant differences in plasma free 3-MT and catecholamines' diagnostic positive rate between the MNs normal group and MNs elevated group, but the rate for plasma CgA was significantly decreased in the MNs normal group (2/5 vs. 41/43, P=0.005). No significant difference was found for the incidence of typical findings by enhanced CT between the two groups. In these eight MNs normal patients, six were diagnosed with PPGL by the previous history of PPGL, typical symptoms and CT findings, or elevation of 3-MT, CgA levels or positive results of PET-CT; two patients were misdiagnosed as nonfunctioning adenoma or primary aldosteronism. All these MNs normal patients underwent preoperative management with alpha adrenergic receptor blockers, of whom, one had an average intraoperative arterial pressure < 60 mmHg during surgery. The median follow-up time for the eight patients was 1.5 (0.5－4.5) years. No evidence of new tumors was found on the enhanced CT scans. Two MNs normal patients' plasma 3-MT and (or) CgA decreased to normal. CONCLUSION For patients with adrenal or retroperitoneal tumors, typical symptoms or a previous history of PPGL, normal plasma MNs is not a sufficient exclusion for PPGL. Plasma 3-MT, catecholamine, CgA results and the imaging findings are helpful for the diagnosis of PPGL. We recommend patients with suspected MNs normal PPGL take alpha adrenergic receptor blockers as preoperative blockade, but should avoid overdose. Postoperative follow-up for patients with normal MNs should focus on the positive biochemical markers before surgery.
Adrenal Gland Neoplasms ; Humans ; Metanephrine ; Paraganglioma ; Pheochromocytoma ; Positron Emission Tomography Computed Tomography

PURPOSE: Previous studies on adrenal incidentalomas (AIs) are limited by their retrospective design, small numbers of patients, Western populations, or use of an outdated imaging technique. We investigated the characteristics of AIs in Korean patients and compared them with those reported in the largest retrospective study in Italy to discover the effects of improved imaging techniques and ethnicity differences. MATERIALS AND METHODS: This was a prospective, multicenter, cross-sectional observational study including 1005 Korean patients. Levels of plasma adrenocorticotrophic hormone, 24-h urinary free cortisol (UFC), serum cortisol after a 1 mg-dexamethasone suppression test, 24-h urinary fractionated metanephrine, and plasma aldosterone and plasma renin activity were measured. All AIs were characterized using computed tomography (CT). RESULTS: Compared with the results of the Italian study, AIs in Korean patients were observed more frequently in men and predominantly on the left side. Korean patients with AIs were slightly younger, and fewer patients underwent surgery. Most AIs were nonfunctional in both studies, while fewer subclinical hypercortisolism and more primary aldosteronism (PA) cases were detected in Korean patients. In our study, high UFC levels showed very low sensitivity, compared to those in the Italian study. In pheochromocytoma or PA cases, there were no hormonal differences between the studies. AIs in Korean patients were smaller, such that a lower cutoff size for detecting adrenocortical carcinoma (ACC) could be warranted. CONCLUSION: Recent advances in CT technology were leveraged to provide accurate characteristics of AIs and to detect smaller ACCs.
Adrenocortical Carcinoma ; Adrenocorticotropic Hormone ; Aldosterone ; Cushing Syndrome ; Humans ; Hydrocortisone ; Hyperaldosteronism ; Italy ; Korea* ; Male ; Metanephrine ; Observational Study ; Pheochromocytoma ; Plasma ; Prospective Studies* ; Renin ; Retrospective Studies

Despite all technical progress in modern diagnostic methods and treatment modalities of pheochromocytoma/paraganglioma, early consideration of the presence of these tumors remains the pivotal link towards the best possible outcome for patients. A timely diagnosis and proper treatment can prevent the wide variety of potentially catastrophic cardiovascular complications. Modern biochemical testing should include tests that offer the best available diagnostic performance, measurements of metanephrines and 3-methoxytyramine in plasma or urine. To minimize false-positive test results particular attention should be paid to pre-analytical sampling conditions. In addition to anatomical imaging by computed tomography (CT) or magnetic resonance imaging, new promising functional imaging modalities of photon emission tomography/CT using with somatostatin analogues such as ⁶⁸Ga-DOTATATE (⁶⁸Ga-labeled DOTA(0)-Tyr(3)-octreotide) will probably replace ¹²³I-MIBG (iodine-123-metaiodobenzylguanidine) in the near future. As nearly half of all pheochromocytoma patients harbor a mutation in one of the 14 tumor susceptibility genes, genetic testing and counseling should at least be considered in all patients with a proven tumor. Post-surgical annual follow-up of patients by measurements of plasma or urinary metanephrines should last for at least 10 years for timely detection of recurrent or metastatic disease. Patients with a high risk for recurrence or metastatic disease (paraganglioma, young age, multiple or large tumors, genetic background) should be followed up lifelong.
Catecholamines ; Counseling ; Diagnosis ; Follow-Up Studies ; Genetic Testing ; Humans ; Magnetic Resonance Imaging ; Metanephrine ; Paraganglioma* ; Pheochromocytoma* ; Plasma ; Recurrence ; Somatostatin

A 9-year-old boy presented with increased sweating and abdominal pain. His mother and uncle had been diagnosed with bilateral pheochromocytoma and medullary thyroid carcinoma. Magnetic resonance imaging of the boy's abdomen revealed a 7.5 cm×7.0 cm×6.0 cm mass with a thick peripheral enhancing wall and fluid-fluid level at the right suprarenal region. His ¹²³I-meta-iodobenzylguanidine (MIBG) scan showed a large mass with increased MIBG uptake in the right adrenal gland. The levels of serum norepinephrine, urine epinephrine/norepinephrine, metanephrine, and vanillylmandelic acid were elevated. He, his mother, and two sisters tested positive for the known mutation of multiple endocrine neoplasia type 2A, Cys634Tyr in RET proto-oncogene. Laparoscopic tumor excision and right adrenalectomy were performed. Final diagnosis was pheochromocytoma with malignant behavior, based on adrenal gland scoring scale. However, there was no overt metastasis. After surgery, his symptoms resolved and abnormal laboratory tests were normalized.
3-Iodobenzylguanidine ; Abdomen ; Abdominal Pain ; Adrenal Glands ; Adrenalectomy ; Child ; Diagnosis ; Humans ; Magnetic Resonance Imaging ; Male ; Metanephrine ; Mothers ; Multiple Endocrine Neoplasia Type 2a ; Multiple Endocrine Neoplasia ; Neoplasm Metastasis ; Norepinephrine ; Pheochromocytoma ; Proto-Oncogenes ; Siblings ; Sweat ; Sweating ; Thyroid Neoplasms ; Vanilmandelic Acid

BACKGROUND: Current guidelines for follow-up of adrenal incidentalomas are extensive and hampered by lack of follow-up studies. We tested the hypothesis that small lipid-rich adrenal incidentalomas, initially characterized by tumor size <40 mm and <10 Hounsfield units (HUs) on unenhanced computed tomography (CT) may not demonstrate excessive growth/hormonal hypersecretion on follow-up. METHODS: Sixty-nine incidentalomas in 56 patients were restudied with unenhanced CT and screening for hypercortisolism (dexamethasone suppression test [DST], plasma adrenocorticotropic hormone) and pheochromocytoma (24-hour urinary metanephrines and normetanephrines) 5 years later. Primary hyperaldosteronism was excluded at base-line. RESULTS: Tumor (n=69) size was similar before and after 5 years follow-up (19+/-6 mm vs. 20+/-7 mm). Mean tumor growth was 1+/-2 mm. Largest increase in tumor size was 8 mm, this tumor was surgically removed and histopathology confirmed cortical adenoma. DST was normal in 54 patients and two patients (3.6%) were still characterized by subclinical hypercortisolism. Initial tumor size was >20 mm for the patient with largest tumor growth and those with subclinical hypercortisolism. All patients had normal 24-hour urinary metanephrines and normetanephrines. Low attenuation (<10 HU) was demonstrated in 97% of 67 masses re-evaluated with unenhanced CT. CONCLUSION: None of the patients developed clinically relevant tumor growth or new subclinical hypercortisolism. Biochemical screening for pheochromocytoma in incidentalomas demonstrating <10 HU on unenhanced CT is not needed. For such incidentalomas <40 mm, it seems sufficient to perform control CT and screen for hypercortisolism after 5 years.
Adenoma ; Cushing Syndrome ; Follow-Up Studies* ; Humans ; Hyperaldosteronism ; Mass Screening ; Metanephrine ; Normetanephrine ; Pheochromocytoma ; Plasma ; Prospective Studies*

Adrenocorticotropic hormone (ACTH)-producing pheochromocytoma has been rarely reported, whereas only a few cases of Cushing syndrome accompanied by opportunistic infections have been reported. We experienced a patient with pheochromocytoma with ectopic Cushing syndrome complicated by invasive aspergillosis. A 35-year-old woman presented with typical Cushingoid features. Her basal plasma cortisol, ACTH, and 24-hour urine free cortisol levels were significantly high, and 24-hour urine metanephrine and catecholamine levels were slightly elevated. The endogeneous cortisol secretion was not suppressed by either low- or high-dose dexamethasone. Abdominal computed tomography (CT) revealed a heterogeneous enhancing mass measuring approximately 2.5 cm in size in the left adrenal gland. No definitive mass lesion was observed on sellar magnetic resonance imaging. On fluorine-18 fluorodeoxyglucose positron emission tomography/CT, a hypermetabolic nodule was observed in the left upper lung. Thus, we performed a percutaneous needle biopsy, which revealed inflammation, not malignancy. Thereafter, we performed a laparoscopic left adrenalectomy, and its pathologic finding was a pheochromocytoma with positive immunohistostaining for ACTH. After surgery, the biochemistry was normalized, but the clinical course was fatal despite intensive care because of the invasive aspergillosis that included the lungs, retina, and central nervous system.
Adrenal Glands ; Adrenalectomy ; Adrenocorticotropic Hormone* ; Adult ; Aspergillosis* ; Biochemistry ; Biopsy, Needle ; Central Nervous System ; Cushing Syndrome* ; Dexamethasone ; Electrons ; Female ; Humans ; Hydrocortisone ; Inflammation ; Critical Care ; Lung ; Magnetic Resonance Imaging ; Metanephrine ; Opportunistic Infections ; Pheochromocytoma* ; Plasma ; Retina

High-resolution imaging techniques have increased the detection rate of adrenal incidentaloma. We developed a method of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for detection of plasma free metanephrine (MN) and normetanephrine (NMN) and evaluated its analytical performance and clinical efficacy in differential diagnosis of adrenal incidentaloma. After solid-phase extraction, chromatographic isolation of the analytes and internal standard was achieved by column elution in the LC-MS/MS system. The analytes were detected in multiple-reaction monitoring mode by using positive electrospray ionization: MN, transition m/z 180.1-->165.1; NMN, m/z 166.1-->134.1. This method was validated for linearity, precision, accuracy, lower limits of quantification and detection, extraction recovery, and the matrix effect. Plasma concentrations of MN and NMN of 14 patients with pheochromocytoma were compared with those of 17 healthy volunteers, 10 patients with essential hypertension, and 60 patients with adrenal adenoma. The assay's linear range was 0.04-50.0 and 0.08-100.0 nmol/L for MN and NMN, respectively. Assay imprecision was 1.86-7.50%. The accuracy ranged from -7.50% to 2.00%, and the mean recovery of MN and NMN was within the range 71.5-95.2%. Our LC-MS/MS method is rapid, accurate, and reliable and useful for differential diagnosis of adrenal incidentaloma.
Adenoma ; Diagnosis, Differential* ; Healthy Volunteers ; Humans ; Hypertension ; Mass Spectrometry* ; Metanephrine ; Normetanephrine ; Pheochromocytoma ; Plasma*

A 53-year-old woman had a 1.7 cm left adrenal mass on an abdominal computed tomography (CT) scan. She presented with paroxysmal headache, palpitation, sweating, and hypertension. The patient was highly suspected of having a pheochromocytoma, but measurements of 24-hour urinary metanephrine, catecholamines, and vanillylmandelic acid were normal. Plasma and urine catecholamine levels were within the normal range even during paroxysmal episodes. A scintigraphic study with 131I-metaiodobenzylguanidine (MIBG) revealed selective concentration of the radiotracer, corresponding to the CT mass. The patient underwent a left adrenalectomy and the pathological examination confirmed the diagnosis of pheochromocytoma. In this report, we describe a rare case of a symptomatic pheochromocytoma with normal catecholamine levels. Our case illustrates that routine nuclear scintigraphy, such as 131I-MIBG, should be performed even in cases with normal hormonal testing for all patients with high clinical suspicion of pheochromocytoma.
3-Iodobenzylguanidine ; Adrenalectomy ; Catecholamines ; Female ; Headache ; Humans ; Hypertension ; Metanephrine ; Middle Aged ; Pheochromocytoma ; Plasma ; Reference Values ; Sweat ; Sweating ; Vanilmandelic Acid

PURPOSE: Pheochromocytoma is a catecholamine-producing tumor that arises from the chromaffin cells of the adrenal medulla or the sympathetic ganglia. This study was undertaken to evaluate the clinical profiles of children with pheochromocytoma. METHODS: We retrospectively reviewed the clinical, radiological and outcome of 16 children who had been diagnosed as pheochromocytoma from May, 1984 to July, 2006 in the department of pediatrics, Seoul National University Hospital. RESULTS: The mean age at diagnosis was 12.3+/-3.4 years (range, 7.1-20 yrs). The male to female ratio was 10:6. The major symptoms were hypertension in 87.5%, sweating in 75%, tachycardia in 68.8% and headache in 62.5%. The sensitivities of 24 hour urinary norepinephrine and metanephrine were 100 %. All tumors were localized by combined study of CT, ultrasonography, MRI or (123)I-MIBG scan. Single (123)I- MIBG scan had sensitivity as 92.9%. Sporadic cases were 13 (81.3%). Bilateral pheochromocytomas were observed in 6 patients (37.5%). The pheochromocytoma developed in 6 patients with underling disease; von Hippel-Lindau (VHL) syndrome (3), neurofibromatosis (1), and cyanotic congenital heart diseases (2). Adrenalectomy was performed in 13 patients, and tumorectomy was in 3 patients. Two patients were diagnosed as malignant pheochromocytoma. CONCLUSION: Because the symptoms are deceptive and variable, the hormonal and radiological study should be performed carefully in suspected cases. The pheochromocytoma can now be operated safely. The tumor might present as a component of other syndromes such as multiple endocrine neoplasia type 2, neurofibromatosis, and VHL syndrome. Thus comprehensive consideration is needed at initial diagnostic approach.
3-Iodobenzylguanidine ; Adolescent ; Adrenal Medulla ; Adrenalectomy ; Child ; Chromaffin Cells ; Female ; Ganglia, Sympathetic ; Headache ; Heart Diseases ; Humans ; Hypertension ; Male ; Metanephrine ; Multiple Endocrine Neoplasia Type 2a ; Neurofibromatoses ; Norepinephrine ; Pediatrics ; Pheochromocytoma ; Retrospective Studies ; Sweat ; Sweating ; Tachycardia

The coexpression of cortical and medullary features in a single adrenal cortical cell has been recognized, leading to terms such as cortico-medullary cells. Here, we reported a case of adrenocortical adenoma consisting of cortico-medullary cells that clinically mimicked pheochromocytoma. A 52-year-old woman was admitted to our hospital complaining of an 8-month history of paroxysmal palpitation with refractory hypertension. A 24-hour urine study revealed increased norepinephrine and metanephrine levels. Computed tomography of the abdomen revealed a 1.0x0.9-cm mass in the left adrenal gland. The patient subsequently underwent unilateral laparoscopic adrenalectomy for a presumptive pheochromocytoma. Light microscopic findings of the left adrenal mass indicated an adrenocortical adenoma, but electron microscopy identified lipid vacuoles and smooth endoplasmic reticulum, along with dense core neurosecretory granules, so-called cortico-medullary cells. This is the first report of the detection of cortico-medullary cells in adrenocortical adenoma presenting as pheochromocytoma in Korea.
Abdomen ; Adrenal Glands ; Adrenalectomy ; Adrenocortical Adenoma ; Endoplasmic Reticulum, Smooth ; Female ; Humans ; Hypertension ; Light ; Metanephrine ; Microscopy, Electron ; Middle Aged ; Norepinephrine ; Pheochromocytoma ; Vacuoles