Predictive model of pheochromocytoma based on the imaging features of the adrenal tumours.

The purpose of our study was to develop a predictive model to rule out pheochromocytoma among adrenal tumours, based on unenhanced computed tomography (CT) and/or magnetic resonance imaging (MRI) features. We performed a retrospective multicentre study of 1131 patients presenting with adrenal lesions including 163 subjects with histological confirmation of pheochromocytoma (PHEO), and 968 patients showing no clinical suspicion of pheochromocytoma in whom plasma and/or urinary metanephrines and/or catecholamines were within reference ranges (non-PHEO). We found that tumour size was significantly larger in PHEO than non-PHEO lesions (44.3 ± 33.2 versus 20.6 ± 9.2 mm respectively; P < 0.001). Mean unenhanced CT attenuation was higher in PHEO (52.4 ± 43.1 versus 4.7 ± 17.9HU; P < 0.001). High lipid content in CT was more frequent among non-PHEO (83.6% versus 3.8% respectively; P < 0.001); and this feature alone had 83.6% sensitivity and 96.2% specificity to rule out pheochromocytoma with an area under the receiver operating characteristics curve (AUC-ROC) of 0.899. The combination of high lipid content and tumour size improved the diagnostic accuracy (AUC-ROC 0.961, sensitivity 88.1% and specificity 92.3%). The probability of having a pheochromocytoma was 0.1% for adrenal lesions smaller than 20 mm showing high lipid content in CT. Ninety percent of non-PHEO presented loss of signal in the "out of phase" MRI sequence compared to 39.0% of PHEO (P < 0.001), but the specificity of this feature for the diagnosis of non-PHEO lesions low. In conclusion, our study suggests that sparing biochemical screening for pheochromocytoma might be reasonable in patients with adrenal lesions smaller than 20 mm showing high lipid content in the CT scan, if there are no typical signs and symptoms of pheochromocytoma.

Updated reference intervals for urine normetanephrine have no effect on test sensitivity but fewer false positives.

OBJECTIVE: We previously highlighted the problem of frequent false positives in 24 h urine normetanephrine(UNM) measurements owing to reference intervals that are inappropriately low for the population being screened for pheochromocytoma. Using a large population database, we devised new age-stratified reference intervals for the 24 h UNM test that were higher compared to previous. However, it was uncertain as to whether this would compromise test sensitivity for true pheochromocytoma cases. DESIGN AND METHODS: Retrospective analysis of all pheochromocytoma cases from a recently constructed provincial registry. All confirmed cases had their diagnostic UNM results retrospectively re-analysed according to the newly proposed UNM reference intervals to determine the percentage and phenotype of cases that might have been theoretically missed with the new reference range. RESULTS: After excluding pediatric and non-secretory head and neck paragangliomas, there were 60 confirmed pheochromocytoma cases. Using prior reference intervals, 51/60 (85%) had an abnormally high UNM. Of the 9 with normal UNM, 4 had a high urine metanephrine(UMN), 5 had normal levels of both UNM and UMN such that 55/60 had abnormal test results, representing the historical combined test sensitivity of 92%. Using the proposed reference interval, 43/60 (72%) had high UNM results. Of the 17 with normal UNM, 12 had high UMN, 5 had normal levels of both UNM and UMN. Therefore, 55/60 patients had had elevations in either UNM or UMN, corresponding to an identical combined test sensitivity of 92%. CONCLUSIONS: Reference intervals for UNM derived from actual clinical population screening data are higher than in traditional healthy volunteers. Use of these more appropriate reference intervals can significantly reduce the false positive rate without compromising test sensitivity for true pheochromocytoma.

Plasma Steroid Profiling in Patients With Adrenal Incidentaloma.

CONTEXT: Most patients with adrenal incidentaloma have nonfunctional lesions that do not require treatment, while others have functional or malignant tumors that require intervention. The plasma steroid metabolome may be useful to assess therapeutic need. OBJECTIVE: This work aimed to establish the utility of plasma steroid profiling combined with metanephrines and adrenal tumor size for the differential diagnosis of patients with adrenal incidentaloma. METHODS: This retrospective cross-sectional study, which took place at 7 European tertiary-care centers, comprised 577 patients with adrenal incidentaloma, including 19, 77, 65, 104 and 312 respective patients with adrenocortical carcinoma (ACC), pheochromocytoma (PHEO), primary aldosteronism (PA), autonomous cortisol secretion (ACS), and nonfunctional adrenal incidentaloma (NFAI). Mesaures of diagnostic performance were assessed (with [95% CIs]) for discriminating different subgroups of patients with adrenal incidentaloma. RESULTS: Patients with ACC were characterized by elevated plasma concentrations of 11-deoxycortisol, 11-deoxycorticosterone, 17-hydroxyprogesterone, androstenedione, and dehydroepiandrosterone-sulfate, whereas patients with PA had elevations of aldosterone, 18-oxocortisol, and 18-hydroxycortisol. A selection of those 8 steroids, combined with 3 others (cortisol, corticosterone, and dehydroepiandrosterone) and plasma metanephrines, proved optimal for identifying patients with ACC, PA, and PHEO at respective sensitivities of 83.3% (66.1%-100%), 90.8% (83.7%-97.8%), and 94.8% (89.8%-99.8%); and specificities of 98.0% (96.9%-99.2%), 92.0% (89.6%-94.3%), and 98.6% (97.6%-99.6%). With the addition of tumor size, discrimination improved further, particularly for ACC (100% [100%-100%] sensitivity, 99.5% [98.9%-100%] specificity). In contrast, discrimination of ACS and NFAI remained suboptimal (70%-71% sensitivity, 89%-90% specificity). CONCLUSION: Among patients with adrenal incidentaloma, the combination of plasma steroid metabolomics with routinely available plasma free metanephrines and data from imaging studies may facilitate the identification of almost all clinically relevant adrenal tumors.

Attenuation Value in Adrenal Incidentalomas: A Longitudinal Study.

Context: A tendency to grow has been reported in adrenal incidentalomas. However, long-term data regarding attenuation value, a measure of lipid content, are not available. Aim: This study aims to collect radiological data (diameter in mm and attenuation value in Hounsfield units, HU) with computed tomography (CT) in adrenal incidentalomas, in order to compare baseline characteristics with the last follow-up imaging. Design: This is a longitudinal study which included patients with a new diagnosis of adrenal incidentaloma, evaluated from January 2002 to June 2020. Setting: Referral University-Hospital center. Patients: Two hundred seventy-seven patients with 355 different cortical adenomas (baseline group) were evaluated at the first outpatient visit; the follow-up cohort consists of 181 patients with 234 adenomas (12-175 months after baseline). Inclusion criteria were conservative management and radiological features able to minimize malignancy or risk of progression. Main Outcome Measure: CT modification according to endocrine function: autonomous cortisol secretion (ACS) if cortisol >50 nmol/L after 1-mg dexamethasone test (DST). Results: At baseline CT, mean diameter was 18.7 mm and attenuation value was 0.8 HU (higher in ACS, 66 cases >10 HU), without modification in early imaging (12-36 months). The size increased over time (r = 0.289), achieving the largest differences after at least 60 months of follow-up (mean diameter, +2 mm; attenuation value, -4 HU), combined with a reduction in the attenuation value (r = -0.195, especially in patients with ACS). Lipid-poor adenomas (>10 HU) presented a reduced cortisol suppression after 1-mg DST, an increase in size and the largest decrease in attenuation value during follow-up. Univariate analysis confirmed that larger adenomas presented reduced suppression after DST and increase in size during follow-up. Conclusions: Growth is clinically modest in adrenal incidentaloma: the first follow-up CT 5 years after baseline is a reasonable choice, especially in ACS. Mean density is increased in patients with ACS and overt hypercortisolism. Mean density reduces during follow-up in all adrenal adenomas, suggesting an increase in lipid content, especially in those with ACS.

Assessment of Plasma-Free Cortisol Concentrations by LC-MS/MS in Patients with Autonomous Cortisol Secretion.

Autonomous cortisol secretion (ACS) of an adrenal incidentaloma (AI) is associated with mild cortisol excess that could result in poor metabolic and cardiovascular outcomes. The biological activity of glucocorticoids depends on the unbound, free fraction. We aimed to evaluate plasma free cortisol (FC) concentrations in patients with ACS in this cross-sectional study. One hundred and ten AI patients in 3 groups; non-functioning (NFA, n=33), possible ACS (n=65), ACS (n=12) were enrolled. Following measurements were conducted: Clinical data and total serum cortisol (TC), plasma corticotrophin (ACTH), serum dehydroepiandrosterone sulfate (DHEA-S), cortisol after 1 mg dexamethasone by both immunoassay and LC-MS/MS (DexF), serum corticosteroid binding globulin (CBG), plasma dexamethasone concentration [DEX] and plasma FC by LC-MS/MS. Patients with ACS featured an unfavorable metabolic profile. Plasma [DEX] and serum CBG levels were similar between groups. Plasma FC was significantly higher in ACS when compared to NFA and possible ACS groups p<0.05 and p<0.01, respectively. In multiple regression analysis DexF (beta=0.402, p<0.001) and CBG (beta=-0.257, p=0.03) remained as the independent predictors of plasma FC while age, sex, BMI, smoking habit, and existing cardiovascular disease did not make a significant contribution to the regression model. In conclusion, the magnitude of cortisol excess in ACS could lead to increased plasma FC concentrations. Further studies in AI patients are needed to demonstrate whether any alterations of cortisol affinity for CBG exist and to establish whether plasma FC concentrations predict the unfavorable metabolic profile in ACS.

Diagnostic accuracy of the different hormonal tests used for the diagnosis of autonomous cortisol secretion.

To evaluate the diagnostic accuracy of the different tests commonly used in the evaluation of adrenal incidentalomas (AIs) for the identification of autonomous cortisol secretion (ACS) and comorbidities potentially related to ACS. In a retrospective study of patients with AIs ≥ 1 cm, we evaluated the diagnostic reliability and validity of the dexamethasone suppression test (DST), urinary free cortisol (UFC), ACTH, late-night salivary cortisol (LNSC), and dehydroepiandrosterone-sulphate (DHEAS) for the diagnosis of comorbidities potentially related to ACS. Diagnostic indexes were also calculated for UFC, ACTH, LNSC, and DHEAS considering DST as the gold standard test for the diagnosis of ACS, using three different post-DST cortisol thresholds (138 nmol/L, 50 nmol/L and 83 nmol/L). We included 197 patients with AIs in whom the results of the five tests abovementioned were available. At diagnosis, 85.9% of patients with one or more AIs had any comorbidity potentially related to ACS, whereas 9.6% had ACS as defined by post-DST cortisol > 138 nmol/L. The reliability of UFC, ACTH, LNSC, and DHEAS for the diagnosis of ACS was low (kappa index < 0.30). Of them, LNSC reached the highest diagnosis accuracy for ACS identification (AUC = 0.696 [95% CI 0.626-0.759]). The diagnostic performances of these tests for comorbidities potentially related to ACS was poor; of them, the DST was the most accurate (AUC = 0.661 [95% CI 0.546-0.778]) and had the strongest association with these comorbidities (OR 2.6, P = 0.045). Patients presenting with increased values of both DST and LNSC had the strongest association with hypertension (OR 7.1, P = 0.002) and with cardiovascular events (OR 3.6, P = 0.041). In conclusion, LNSC was the test showing the highest diagnosis accuracy for the identification of ACS when a positive DST was used as the gold standard for its diagnosis. The DST test showed the strongest association with comorbidities potentially related to ACS. The definition of ACS based on the combination of elevated DST and LNSC levels improved the identification of patients with increased cardiometabolic risk.

C-kit, flt-3, PDGFR-ß, and VEGFR2 expression in canine adrenal tumors and correlation with outcome following adrenalectomy.

The objective of this retrospective study was to evaluate the expression of receptor tyrosine kinases (RTKs) in canine adrenal tumors and correlate this expression with features of tumor aggressiveness and survival in dogs undergoing adrenalectomy. Forty-three canine adrenal tumors were evaluated for expression of c-kit, fms-like tyrosine kinase 3 (flt-3), platelet-derived growth factor receptor-ß (PDGFR-ß), and vascular endothelial growth factor receptor 2 (VEGFR2) using immunohistochemistry. Tumor RTK staining characteristics were compared to normal adrenals. Medical records were reviewed for data regarding patient outcome and tumor characteristics. Expression of c-kit, flt-3, PDGFR-ß, and VEGFR2 was detected in 26.9%, 92.3%, 96.2%, and 61.5% of cortical tumors and 0%, 63.2%, 47.4%, and 15.8% of pheochromocytomas, respectively. Expression of RTKs was not significantly increased when compared to normal adrenals and did not correlate with survival after adrenalectomy. Receptor tyrosine kinases are not overexpressed in canine adrenal tumors compared to normal adrenal tissue. Therapeutic inhibition of these receptors may still represent an effective approach in cases where receptor activation is present.

L'objectif de cette étude rétrospective était d'évaluer l'expression des récepteurs tyrosine kinases (RTKs) dans les tumeurs surrénales canines et de corréler cette expression avec des caractéristiques d'agressivité tumorale et de survie chez les chiens subissant une surrénalectomie.Quarante-trois tumeurs surrénales canines ont été évaluées pour l'expression de c-kit, de la tyrosine kinase 3 de type fms (flt-3), du récepteur du facteur de croissance dérivé des plaquettes-ß (PDGFR-ß) et du récepteur du facteur de croissance endothélial vasculaire 2 (VEGFR2) par immunohistochimie. Les caractéristiques de coloration de la tumeur RTK ont été comparées à celles des surrénales normales. Les dossiers médicaux ont été examinés pour les données concernant les résultats des patients et les caractéristiques de la tumeur. L'expression de c-kit, flt-3, PDGFR-ß et VEGFR2 a été détectée dans 26,9 %, 92,3 %, 96,2 % et 61,5 % des tumeurs corticales et 0 %, 63,2 %, 47,4 % et 15,8 % des phéochromocytomes, respectivement. L'expression des RTK n'était pas significativement augmentée par rapport aux surrénales normales et n'était pas corrélée avec la survie après surrénalectomie. Les récepteurs tyrosine kinases ne sont pas surexprimés dans les tumeurs surrénales canines par rapport au tissu surrénalien normal. L'inhibition thérapeutique de ces récepteurs peut encore représenter une approche efficace dans les cas où l'activation du récepteur est présente.(Traduit par Docteur Serge Messier).

Study of stability and interference for catecholamines and metanephrines, 3-methoxytyramine: key point of an accurate diagnosis for pheochromocytoma and paraganglioma.

BACKGROUND: Accurate diagnosis of pheochromocytoma and paraganglioma (PPGLs) is highly dependent on the detection of metanephrines and catecholamines. However, the systematic investigation on influencing factors including specimen (plasma or whole blood), anticoagulant, storage conditions, and interference factors need further confirmation. METHODS: Blood with heparin-lithium or EDTA-K2 were collected, stability of epinephrine (EPI), norepinephrine (NE), dopamine (DA), metanephrine (MN), normetanephrine (NMN), 3-methoxytyramine (3-MT) in whole blood and plasma at room temperature and 4 °C for different storage times, stability of plasma MN, NMN and 3-MT at -20 °C and -80 °C were investigated. Plasma with hemoglobin (1 g/L, 2 g/L, 3 g/L, 4 g/L, 6 g/L), TG (<5 mmol/L, 5-8 mmol/L, >8 mmol/L) were prepared. RESULTS: EPI, NE, DA were prone to degrade at room temperature, samples should be centrifuged at 4 °C. EPI and NE were stable in whole blood at 4 °C for 4 h and in plasma for 2 h. For MN, NMN, 3-MT, plasma can be stable at room temperature and 4 °C for at least 6 h, which is better than whole blood; there was no significant difference when stored at -20 °C and -80 °C for 7 days. Heparin-lithium had a slight advantage over EDTA-K2. EPI, NE, DA should not be performed when Hb > 1 g/L or TG > 5 mmol/L. MN, NMN, 3-MT should not be performed when Hb > 2 g/L, whereas TG had no interference. CONCLUSIONS: According to the actual clinical application scenario, this study provided a reliable basis for the accurate diagnosis of PPGLs.

Plasma Metabolome Profiling for the Diagnosis of Catecholamine Producing Tumors.

Context: Pheochromocytomas and paragangliomas (PPGL) cause catecholamine excess leading to a characteristic clinical phenotype. Intra-individual changes at metabolome level have been described after surgical PPGL removal. The value of metabolomics for the diagnosis of PPGL has not been studied yet. Objective: Evaluation of quantitative metabolomics as a diagnostic tool for PPGL. Design: Targeted metabolomics by liquid chromatography-tandem mass spectrometry of plasma specimens and statistical modeling using ML-based feature selection approaches in a clinically well characterized cohort study. Patients: Prospectively enrolled patients (n=36, 17 female) from the Prospective Monoamine-producing Tumor Study (PMT) with hormonally active PPGL and 36 matched controls in whom PPGL was rigorously excluded. Results: Among 188 measured metabolites, only without considering false discovery rate, 4 exhibited statistically significant differences between patients with PPGL and controls (histidine p=0.004, threonine p=0.008, lyso PC a C28:0 p=0.044, sum of hexoses p=0.018). Weak, but significant correlations for histidine, threonine and lyso PC a C28:0 with total urine catecholamine levels were identified. Only the sum of hexoses (reflecting glucose) showed significant correlations with plasma metanephrines.By using ML-based feature selection approaches, we identified diagnostic signatures which all exhibited low accuracy and sensitivity. The best predictive value (sensitivity 87.5%, accuracy 67.3%) was obtained by using Gradient Boosting Machine Modelling. Conclusions: The diabetogenic effect of catecholamine excess dominates the plasma metabolome in PPGL patients. While curative surgery for PPGL led to normalization of catecholamine-induced alterations of metabolomics in individual patients, plasma metabolomics are not useful for diagnostic purposes, most likely due to inter-individual variability.

DHEAS and Differential Blood Counts as Indirect Signs of Glucocorticoid Excess in Adrenal Non-Producing Adenomas.

The majority of incidentally discovered adrenal tumors are later characterized as non-producing adrenocortical adenomas (NPA). We asked whether laboratory abnormalities in parameters that reflect glucocorticoid action can be found in patients with NPA despite their nature of being clinically unapparent. Since glucocorticoids are potent immunosuppressants we studied blood counts and differential blood counts along with corticotropin and dehydroepiandrostenedione sulfate (DHEAS) blood concentrations, as well as cortisol values before and after an overnight 1 mg dexamethasone suppression test. We compared the results of normal individuals, of patients with adrenal adenomas and normal hormone profiles and with subclinical autonomous glucocorticoid hypersecretion, as well as overt cortisol excess. We found that almost all indices of the blood counts were significantly different between the patients groups. In particular, patients with adrenal non-producing adenomas already showed signs of glucocorticoid excess, including relative lymphocytopenia, lowered DHEAS, and ACTH concentrations than control individuals. We also found that the extent of lymphocytopenia correlated with the concentrations of DHEAS and ACTH, and DHEAS correlated well with ACTH. We conclude that the basal ACTH and DHEAS values along with the differential blood counts give good information on the extent of glucocorticoid excess and that silent adrenal adenomas seem to oversecrete glucocorticoids at concentrations that already alter these parameters.

Circulating adrenomedullin and B-type natriuretic peptide do not predict blood pressure fluctuations during pheochromocytoma resection: a cross-sectional study.

BACKGROUND: Despite adequate presurgical management, blood pressure fluctuations are common during resection of pheochromocytoma or sympathetic paraganglioma (PPGL). To a large extent, the variability in blood pressure control during PPGL resection remains unexplained. Adrenomedullin and B-type natriuretic peptide, measured as MR-proADM and NT-proBNP, respectively, are circulating biomarkers of cardiovascular dysfunction. We investigated whether plasma levels of MR-proADM and NT-proBNP are associated with blood pressure fluctuations during PPGL resection. METHODS: Study subjects participated in PRESCRIPT, a randomized controlled trial in patients undergoing PPGL resection. MR-proADM and NT-proBNP were determined in a single plasma sample drawn before surgery. Multivariable linear and logistic regression analyses were used to explore associations between these biomarkers and blood pressure fluctuations, use of vasoconstrictive agents during surgery as well as the occurrence of perioperative cardiovascular events. RESULTS: A total of 126 PPGL patients were included. Median plasma concentrations of MR-proADM and NT-proBNP were 0.51 (0.41-0.63) nmol/L and 68.7 (27.9-150.4) ng/L, respectively. Neither MR-proADM nor NT-proBNP were associated with blood pressure fluctuations. There was a positive correlation between MR-proADM concentration and the cumulative dose of vasoconstrictive agents (03B2 0.44, P =0.001). Both MR-proADM and NT-proBNP were significantly associated with perioperative cardiovascular events (OR: 5.46, P =0.013 and OR: 1.54, P =0.017, respectively). CONCLUSIONS: plasma MR-proADM or NT-proBNP should not be considered as biomarkers for the presurgical risk assessment of blood pressure fluctuations during PPGL resection. Future studies are needed to explore the potential influence of these biomarkers on the intraoperative requirement of vasoconstrictive agents and the perioperative cardiovascular risk.

Case Report: Malignant Pheochromocytoma Without Hypertension Accompanied by Increment of Serum VEGF Level and Catecholamine Cardiomyopathy.

Introduction: Pheochromocytoma is a catecholamine-producing tumor in the adrenal medulla and is often accompanied by hypertension, hyperglycemia, hypermetabolism, headache, and hyperhidrosis, and it is classified as benign and malignant pheochromocytoma. In addition, persistent hypertension is often observed in subjects with malignant pheochromocytoma. Case Presentation: A 52-year-old Japanese male was referred and hospitalized in our institution. He had a health check every year and no abnormalities had been pointed out. In addition, he had no past history of hypertension. In endocrinology markers, noradrenaline level was as high as 7,693 pg/ml, whereas adrenaline level was within normal range. Abdominal contrast-enhanced computed tomography revealed a 50-mm hyper-vascularized tumor with calcification in the right adrenal gland and multiple hyper-vascularized tumors in the liver. In 131I MIBG scintigraphy, there was high accumulation in the right adrenal gland and multiple accumulation in the liver and bone. In echocardiography, left ventricular ejection fraction was as low as 14.3%. In coronary angiography, however, there was no significant stenosis in the coronary arteries. Based on these findings, we finally diagnosed him as malignant pheochromocytoma accompanied by multiple liver and bone metastases and catecholamine cardiomyopathy. However, blood pressure was continuously within normal range without any anti-hypertensive drugs. Right adrenal tumor resection was performed together with left hepatic lobectomy and cholecystectomy. Furthermore, serum levels of vascular endothelial growth factor (VEGF) and parathyroid (PTH)-related protein were very high before the operation but they were markedly reduced after the operation. Conclusions: This is the first report showing the time course of serum VEGF level in a subject with malignant pheochromocytoma, clearly showing that malignant pheochromocytoma actually secreted VEGF. In addition, this case report clearly shows that we should bear in mind once again that malignant pheochromocytoma is not necessarily accompanied by hypertension.

A case of primary aldosteronism with a negative aldosterone-to-renin ratio.

BACKGROUND: Primary aldosteronism (PA), as a cause of secondary hypertension, can cause more serious cardiovascular damage than essential hypertension. The aldosterone-to-renin ratio (ARR) is recommended as the most reliable screening method for PA, but ARR screening is often influenced by many factors. PA cannot be easily excluded when negative ARR. CASE PRESENTATION: We report the case of a 45-year-old Chinese man with resistant hypertension. Three years ago, he underwent a comprehensive screening for secondary hypertension, including the ARR, and the result was negative. After that, the patient's blood pressure was still poorly controlled with four kinds of antihypertensive drugs, the target organ damage of hypertension progressed, and hypokalaemia was difficult to correct. When the patient was hospitalized again for comprehensive examination, we found that aldosterone levels had significantly increased, although the ARR was negative. An inhibitory test with saline was further carried out, and the results suggested that aldosterone was not inhibited; therefore, PA was diagnosed. We performed a unilateral adenoma resection for this patient, and spironolactone was continued to control blood pressure. After the operation, blood pressure is well controlled, and hypokalaemia is corrected. CONCLUSION: When the ARR is negative, PA cannot be easily excluded. Comprehensive analysis and diagnosis should be based on the medication and clinical conditions of patients.

Optimized procedures for testing plasma metanephrines in patients on hemodialysis.

Diagnosis of pheochromocytomas and paragangliomas in patients receiving hemodialysis is troublesome. The aim of the study was to establish optimal conditions for blood sampling for mass spectrometric measurements of normetanephrine, metanephrine and 3-methoxytyramine in patients on hemodialysis and specific reference intervals for plasma metanephrines under the most optimal sampling conditions. Blood was sampled before and near the end of dialysis, including different sampling sites in 170 patients on hemodialysis. Plasma normetanephrine concentrations were lower (P < 0.0001) and metanephrine concentrations higher (P < 0.0001) in shunt than in venous blood, with no differences for 3-methoxytyramine. Normetanephrine, metanephrine and 3-methoxytyramine concentrations in shunt and venous blood were lower (P < 0.0001) near the end than before hemodialysis. Upper cut-offs for normetanephrine were 34% lower when the blood was drawn from the shunt and near the end of hemodialysis compared to blood drawn before hemodialysis. This study establishes optimal sampling conditions using blood from the dialysis shunt near the end of hemodialysis with optimal reference intervals for plasma metanephrines for the diagnosis of pheochromocytomas/paragangliomas among patients on hemodialysis.

Correlation Between Plasma Catecholamines, Weight, and Diabetes in Pheochromocytoma and Paraganglioma.

CONTEXT: Pheochromocytomas and paragangliomas (PCC/PGL) are neuroendocrine tumors with discrete catecholamine profiles that cause incompletely understood metabolic and physiologic changes. OBJECTIVE: The objective was to evaluate relationships between plasma catecholamines, body weight, and hemoglobin A1c (HbA1c). We hypothesized that individual catecholamines would correlate negatively with weight and glucose control. DESIGN: A retrospective cohort study was performed (1999-2020). Wilcoxon rank-sum tests compared nonparametric, continuous variables; mixed-effect linear modeling (MEM) evaluated relationships between catecholamines and weight or HbA1c. The median study duration was 54.2 months [interquartile range (IQR) 19.0-95.1]. SETTING: Tertiary academic hospital. PATIENTS: 360 patients were identified prospectively by referral to our center for management or surveillance of PCC/PGL. The median age was 59 years (IQR 45-67) and 56.4% (n = 203) were female. MAIN OUTCOME MEASURES: The primary and secondary outcomes were weight and HbA1c, respectively. RESULTS: On multivariable MEM, norepinephrine (P < 0.0005) negatively correlated with weight when all catecholamines and their derivatives were tried in the model, and normetanephrine (P < 0.0005) correlated when only metanephrines were included. In the surgical cohort (n = 272), normetanephrine decreased postoperatively and was inversely associated with weight (P < 0.0005). Elevated norepinephrine or normetanephrine at the study termination, indicative of metastatic and/or recurrent disease (MRD), correlated with weight loss. Norepinephrine and normetanephrine (P < 0.0005) directly correlated with HbA1c. CONCLUSION: Plasma norepinephrine and its metabolite directly correlate with HbA1c and inversely correlate with weight in PCC/PGL. After resection, declining normetanephrine levels correlate with improving HbA1c despite an increase in patient body weight. Persistently elevated catecholamines and decreasing weight are observed in MRD.

Association Between Mortality and Levels of Autonomous Cortisol Secretion by Adrenal Incidentalomas : A Cohort Study.

BACKGROUND: Autonomous cortisol secretion in patients with adrenal incidentalomas is associated with increased mortality, but detailed information about the risk associated with specific levels of autonomous cortisol secretion is not available. OBJECTIVE: To measure the association between mortality and levels of autonomous cortisol secretion in patients with adrenal incidentalomas. DESIGN: Retrospective cohort study. (ClinicalTrials.gov: NCT03919734). SETTING: Two hospitals in southern Sweden. PATIENTS: Consecutive patients who had adrenal incidentalomas identified between 2005 and 2015 and were followed for up to 14 years. Outcome data were collected from national registers. MEASUREMENTS: Patients were grouped according to plasma cortisol level after a 1-mg dexamethasone suppression test (cortisolDST; <50, 50 to 82, 83 to 137, or ≥138 nmol/L). RESULTS: During a median follow-up of 6.4 years, 170 of 1048 patients died. Compared with a cortisolDST less than 50 nmol/L, a cortisolDST of 50 to 82 nmol/L was not associated with increased mortality (hazard ratio [HR], 1.15 [95% CI, 0.78 to 1.70]). However, a cortisolDST of 83 to 137 nmol/L (n = 119) had an HR of 2.30 (CI, 1.52 to 3.49), and a cortisolDST of 138 nmol/L or higher (n = 82) had an HR of 3.04 (CI, 1.86 to 4.98). Analyses using restricted cubic splines indicated that the association between cortisolDST and mortality was linear up to a cortisolDST of 200 nmol/L. LIMITATION: The results are not based on verified autonomous cortisol secretion; thus, the association may be underestimated. CONCLUSION: The association between mortality and cortisolDST increased linearly until cortisolDST reached 200 nmol/L. A cortisolDST of 83 to 137 nmol/L was associated with a 2-fold increase in mortality, and a cortisolDST of 138 nmol/L or higher was associated with a 3-fold increase in mortality. Additional studies should be done, and until those studies are completed some clinicians may consider these findings when deciding which patients to recommend for surgery. PRIMARY FUNDING SOURCE: Lisa and Johan Grönberg Foundation and Gyllenstiernska Krapperup Foundation.

Identifying functioning and nonfunctioning adrenal tumors based on blood serum surface-enhanced Raman spectroscopy.

Adrenal tumors are common tumors in urology and they can be further divided into functioning and nonfunctioning tumors according to whether there is uncommon endocrine function. In clinical practice, the early identification and accurate assessment of adrenal tumors are essential for the guidance of subsequent treatment. However, a nonfunctioning adrenal tumor often lacks obvious clinical symptoms, making it difficult to be timely and precisely diagnosed by conventional examinations. Therefore, a rapid and accurate method for identifying the functioning and nonfunctioning adrenal tumors is urgently required to achieve precise treatment of adrenal tumors. In this study, surface-enhanced Raman spectroscopy was investigated as a diagnostic tool to identify the blood serum samples from healthy volunteers as well as the patients with functioning and nonfunctioning adrenal tumors. Based on the SERS peak analysis, abnormal glycolysis, DNA/RNA, and amino acid metabolites were found to be potential biomarkers for identifying patients with adrenal tumors, while metabolites related to disordered protein catabolism and excessive hormone secretion were expected to further differentiate functioning adrenal tumors from nonfunctioning adrenal tumors. In addition, principal component analysis followed by support vector machine (PCA-SVM) was further applied on those serum SERS measurements, and the classification accuracies of 96.8% and 84.5% were achieved for differentiating healthy group versus adrenal tumor group and functioning adrenal tumor group versus nonfunctioning adrenal tumor group, respectively. The results have demonstrated the prodigious potential of precise adrenal tumor diagnosis by using the blood serum surface-enhanced Raman spectroscopy technique.

Carcinoma of unknown primary origin with isolated adrenal metastasis: a report of two cases.

The adrenal glands are one of the most common sites of malignant tumor metastasis. However, metastatic adrenal carcinoma of unknown primary origin with localized adrenal gland involvement is an extremely rare condition. Herein, we reported two cases of carcinoma of unknown primary origin with isolated adrenal metastasis. In the first case, back pain was the trigger; while in the second case, the triggers were low fever and weight loss. Metabolic abnormalities such as hypertension and obesity were not detected in either case. Neither patient had relevant previous medical histories, including malignancy. However, both had a long-term history of smoking. Systemic imaging studies revealed only adrenal tumors and surrounding lesions. Primary adrenocortical carcinoma was initially suspected, and chemotherapy including mitotane was considered. However, due to difficulty in complete resection of the tumor, core needle tumor biopsies were performed. Histopathological examination of biopsy specimens led to the diagnosis of carcinoma of unknown primary origin with isolated adrenal metastasis. In both cases, additional laboratory testing showed high levels of serum squamous cell carcinoma-related antigen and serum cytokeratin fragment. Malignant lesions confined to the adrenal glands are rare. As in our cases, it could be occasionally difficult to differentiate non-functioning primary adrenocortical carcinoma from metastatic adrenal carcinoma of unknown primary origin localized to the adrenal gland. If the lesion is unresectable and there are elevated levels of several tumor markers with no apparent hormonal excess, core needle tumor biopsy should be considered to differentiate the primary tumor from the metastatic tumor.

Should Adrenal Venous Sampling Be Performed in PA Patients Without Apparent Adrenal Tumors?

Introduction: Some aldosterone-producing micro-adenomas cannot be detected through image inspection. Therefore, adrenal venous sampling (AVS) is often performed, even in primary aldosteronism (PA) patients who have no apparent adrenal tumors (ATs) on imaging. In most of these cases, however, the PA is bilateral. Objective: To clarify the clinical need for AVS in PA patients without apparent ATs, taking into consideration the rates of adrenalectomy. Methods: This is a retrospective cross-sectional study assessing 1586 PA patients without apparent ATs in the multicenter Japan PA study (JPAS). We analyzed which parameters could be used to distinguish unilateral PA patients without apparent ATs from bilateral patients. We also analyzed the prevalences of adrenalectomy in unilateral PA patients. Results: The unilateral subtype without an apparent AT was diagnosed in 200 (12.6%) of 1586 PA patients. Being young and female with a short hypertension duration, normokalemia, low creatinine level, low plasma aldosterone concentration, and low aldosterone-to-renin ratio (ARR) was significantly more common in bilateral than unilateral PA patients. If PA patients without apparent ATs were female and normokalemic with a low ARR (<560 pg/ml per ng/ml/h), the rate of unilateral PA was only 5 (1.1%) out of 444. Moreover, 77 (38.5%) of the 200 did not receive adrenalectomy, despite being diagnosed with the unilateral subtype based on AVS. Conclusion: The low prevalence of the unilateral subtype in PA patients without apparent ATs suggests AVS is not indicated for all of these patients. AVS could be skipped in female normokalemic PA patients without apparent ATs if their ARRs are not high. However, AVS should be considered for male hypokalemic PA patients with high ARRs because the rates of the unilateral subtype are high in these patients.