Adrenal pheochromocytoma impacts three main pathways: cysteine-methionine, pyrimidine, and tyrosine metabolism. / è‚¾ä¸Šè ºå—œé“¬ç»†èƒžç˜¤å½±å“ä¸‰æ¡ä¸»è¦ä»£è°¢é€šè·¯ï¼šåŠèƒ±æ°¨é ¸-è›‹æ°¨é ¸ä»£è°¢ã€å˜§å•¶ä»£è°¢å’Œé ªæ°¨é ¸ä»£è°¢é€šè·¯.

Pheochromocytomas and paragangliomas (PPGLs) cause symptoms by altering the circulation levels of catecholamines and peptide hormones. Currently, the diagnosis of PPGLs relies on diagnostic imaging and the detection of catecholamines. In this study, we used ultra-performance liquid chromatography (UPLC)/quadrupole time-of-flight mass spectrometry (Q-TOF MS) analysis to identify and measure the perioperative differential metabolites in the plasma of adrenal pheochromocytoma patients. We identified differentially expressed genes by comparing the transcriptomic data of pheochromocytoma with the normal adrenal medulla. Through conducting two steps of metabolomics analysis, we identified 111 differential metabolites between the healthy group and the patient group, among which 53 metabolites were validated. By integrating the information of differential metabolites and differentially expressed genes, we inferred that the cysteine-methionine, pyrimidine, and tyrosine metabolism pathways were the three main metabolic pathways altered by the neoplasm. The analysis of transcription levels revealed that the tyrosine and cysteine-methionine metabolism pathways were downregulated in pheochromocytoma, whereas the pyrimidine pathway showed no significant difference. Finally, we developed an optimized diagnostic model of two metabolites, L-dihydroorotic acid and vanylglycol. Our results for these metabolites suggest that they may serve as potential clinical biomarkers and can be used to supplement and improve the diagnosis of pheochromocytoma.

Elevated IL-6 levels in a patient with pheochromocytoma.

Pheochromocytoma is a chromaffin cell-derived adrenal medullary tumour and usually presents with paroxysms of hypertension, palpitations, sweating and headache due to excessive catecholamine release. These tumours can also secrete a variety of bioactive neuropeptides and hormones other than catecholamines, resulting in unusual clinical manifestations. We report a female in her mid-30s who presented with fever, anaemia, thrombocytosis and markedly elevated inflammatory markers. The fever profile, including cultures, was negative. Contrast-enhanced CT of abdomen showed a large solid-cystic right adrenal lesion with elevated plasma-free normetanephrine levels suggestive of pheochromocytoma. The fever persisted despite empirical antibiotics and antipyretics. Interleukin-6 (IL-6) levels were elevated (41.2 pg/mL (3-4 pg/mL)). She was initiated on naproxen (NPX) at a dose of 250 mg two times per day. The patient responded to NPX, and after stabilisation, she underwent an adrenalectomy. There was a complete resolution of fever with normalisation of IL-6 levels postoperatively.

Clinical Significance of Pheochromocytoma Size on the Timing and Extent of Surgery.

INTRODUCTION: Elevated metanephrine and catecholamine levels 3-fold upper limit of normal (ULN) are diagnostic for pheochromocytoma. We sought to determine whether size correlates with biochemical activity or symptoms which could guide timing of surgery. METHODS: Data from consecutive patients undergoing adrenalectomy for pheochromocytoma at our institution over a 10-year period were retrospectively collected. These included maximal lesion diameter on preoperative imaging, plasma/urine metanephrine and/or catecholamine levels, demographic variables and presence of typical paroxysmal symptoms. Receiver operating characteristic curves were used to assess predictive accuracy. RESULTS: Sixty-three patients were included in the analysis (41 females and 22 males). Median age was 56 (43, 69) years. Due to various referring practices, 31 patients had documented 24-h urine metanephrine, 26 had 24-h urine catecholamine, and 52 had fractionated plasma metanephrine levels available for review. Values were converted to fold change compared to ULN and the maximum of all measured values was used for logistic regression. Median tumor size was 3.40 (2.25, 4.55) cm in greatest dimension. Tumor size at which pheochromocytoma produced > 3-fold ULN was ≥2.3 cm (AUC of 0.84). Biochemical activity increased with doubling tumor size (odds ratio = 8, P = 0.0004) or ≥ 1 cm increase in tumor size (odds ratio = 3.03, P = 0.001). 40 patients had paroxysmal symptoms, but there was no significant correlation between tumor size/biochemical activity and symptoms. CONCLUSIONS: In our study, tumor size directly correlated with the degree of biochemical activity and pheochromocytomas ≥2.3 cm produced levels 3 times ULN. These findings may allow clinicians to adjust timing of operative intervention.

Chromogranin A as a diagnostic marker of pheochromocytoma and paraganglioma: A systematic review and meta-analysis.

OBJECTIVES: This work aims to assess the diagnostic value of chromogranin A (CgA) in the laboratory diagnosis of neuroendocrine tumors classified as pheochromocytoma and paraganglioma (PPGL). METHODS: A comprehensive search was performed in PubMed, Embase, the Cochrane Library, and Web of Science databases to obtain relevant studies reporting the diagnostic accuracy of CgA in patients with PPGL. The search involved studies written in English between the time of library inception and May 1, 2023. We computed the pooled sensitivity, specificity, and diagnostic odds ratio (DOR). Additionally, the receiver operating characteristic curve and area under the curve (AUC) were determined. The heterogeneity was assessed using the Chi-square test and the I2 test. The subgroup analyses were performed to investigate the origins of heterogeneity. Stata 15.1 statistical software was used in all data analyses. RESULTS: This meta-analysis included 13 studies involving 1470 patients. CgA had a pooled diagnostic sensitivity of 0.86 (95% CI 0.81-0.91), a specificity of 0.90 (95% CI 0.81-0.95), and a DOR of 57 (95% CI 23-142). CgA had an AUC of 0.93. The studies did not reveal any threshold effect (r = -0.165; p > 0.05). The subgroup analyses revealed that the control group category and the detection method caused the overall heterogeneity. CONCLUSIONS: Our study suggests that CgA is a helpful PPGL biomarker. However, relying solely on CgA for diagnosis is not advisable. A comprehensive approach is essential for accurate diagnosis. Future large-scale research is needed to refine CgA's clinical application.

[Comparison of the effectiveness of various methods for determining the level of metanephrines in the diagnosis of pheochromocytomas].

BACKGROUND: Pheochromocytoma (PHEO) is a tumor from the chromaffin tissue of the adrenal medulla, capable of hyperproduction of catecholamines. The increased production of hormones by the tumor leads to catecholamine crises, which have a pathological effect on all organs and systems. In the primary diagnosis of pheochromocytomas, it is important to determine the level of the metabolite of catecholamines - metanephrines. Currently, in clinical practice, various methods are used to determine the level of this metabolite: in blood plasma or in urine, total or only free form, fractionated analysis or unfractionated. AIM: Comparison of the effectiveness of various methods for determining the level of metanephrines for the diagnosis of pheochromocytomas. MATERIALS AND METHODS: A retrospective single-center cohort study was conducted on a sample of patients who were initially operated on for adrenal neoplasm at the Pirogov St. Petersburg State University High Medical Technology Clinic from November 2007 to December 2022 and who passed analysis to determine the level of blood or urine metanephrins before surgical treatment. The results of tests for metanephrine and tumor size were evaluated. RESULTS: 1088 patients with adrenal neoplasms who underwent surgical treatment were examined, of which 348 had histologically confirmed the presence of pheochromocytoma. Four types of metanephrine assays were compared: free fractionated plasma metanephrines (232 patients), unfractionated daily urine metanephrines (431 patients), fractionated total daily urine metanephrines (427 patients) and fractionated free daily urine metanephrines (178 patients). The greatest sensitivity was demonstrated by the analysis of free fractionated plasma methanephrines (95.4%). Unlike others, the sensitivity of this analysis did not decrease in the group of patients with small pheochromocytomas (3 cm or less). The greatest specificity was demonstrated by the analysis of unfractionated metanephrines in daily urine (97.8%), with the lowest sensitivity among all tests (67.6%). The study of fractionated total daily urine metanephrins showed good results of sensitivity and specificity, only slightly inferior to the best indicators, and the analysis of free daily urine metanephrins demonstrated unexpectedly low efficiency. There is a positive correlation between the level of metanephrine in the blood and the size of the tumor. CONCLUSION: Based on the data obtained, the preferred assays for the primary diagnosis of pheochromocytoma can be considered the determination of fractionated free plasma metanephrines and fractionated total daily urine metanephrines, which is consistent with relevant clinical recommendations. It was found that the size of the tumor correlates with the severity of an increase in the level of metanephrins determined by any of the described methods.

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.

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.

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.

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.

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.

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.

Serum miR-375 for Diagnostic and Prognostic Purposes in Medullary Thyroid Carcinoma.

Purpose: Having previously demonstrated that tissue miR-375 expression in medullary thyroid carcinoma (MTC) tissues is linked to prognosis, the aim of this study was to assess the diagnostic and prognostic value of circulating miR-375 levels in MTC patients. Methods: A series of 68 patients with MTC was retrospectively retrieved and assessed in terms of their clinicopathological characteristics. MiR-375 levels were measured in all patients' presurgical blood samples. Both serum and tissue levels were tested prior to surgery in a subgroup of 57 patients. Serum miR-375 levels were also measured in serum from 49 patients with non-C-cell thyroid nodular diseases (non-CTN), 14 patients with pheochromocytoma, and 19 healthy controls. Results: Circulating miR-375 levels were 101 times higher in the serum of patients with MTC than in all other patients and controls, with no overlap (P < 0.01). No correlation emerged between serum and tissue miR-375 levels. Serum miR-375 levels were higher in MTC patients with N0 than in those with N1 disease (P = 0.01), and also in patients who were biochemically cured than in those who were not (P = 0.02). In the whole series of patients and controls, calcitonin (CT) and serum miR-375 levels were correlated at diagnosis (R2 = 0.40, P < 0.01), but in a U-shaped manner: a positive correlation was found with low CT levels, then the correlation turns negative as CT rises (in MTC patients). A negative correlation was indeed found in MTC patients between serum miR-375 and CT (R2 = -0.10, P = 0.01). On ROC curve analysis, a cut-off of 2.1 for serum miR-375 proved capable of distinguishing between MTC patients and the other patients and controls with a 92.6% sensitivity and a 97.6% specificity (AUC: 0.978, P < 0.01). Conclusions: Serum miR-375 levels can serve as a marker in the diagnosis of MTC, with a remarkable specificity. Serum miR-375 also proved a novel marker of prognosis in this disease. Further in vitro experiments to corroborate our results are currently underway.

Properly Collected Plasma Metanephrines Excludes PPGL After False-Positive Screening Tests.

CONTEXT: False-positive results are common for pheochromocytoma/paraganglioma (PPGL) real-world screening. OBJECTIVE: Determine the correlation between screening urine and seated plasma metanephrines in outpatients where PPGL was absent, compared to meticulously prepared and supine-collected plasma metanephrines with age-adjusted references. DESIGN: Retrospective cohort study. SETTING: Databases from a single-provider provincial laboratory (2012-2018), a validated PPGL registry, and a manual chart review from a specialized endocrine testing unit. PATIENTS: PPGL registry data excluded known PPGL cases from the laboratory database. Outpatients having both urine and plasma metanephrines <90 days apart. METHODS: The correlation between urine and seated plasma measures along with the total positivity rate. All cases of plasma metanephrines drawn in the endocrine unit were reviewed for test indication and test positivity rate. RESULTS: There were 810 non-PPGL pairs of urine and plasma metanephrines in the laboratory database; 46.1% of urine metanephrines were reported high. Of seated outpatient plasma metanephrines drawn a median of 5.9 days later, 19.2% were also high (r = 0.33 and 0.50 for normetanephrine and metanephrine, respectively). In contrast, the meticulously prepared and supine collected patients (n = 139, 51% prior high urine metanephrines) had <3% rate of abnormal high results in patients without known PPGL/adrenal mass. CONCLUSIONS: There was a poor-to-moderate correlation between urine and seated plasma metanephrines. Up to 20% of those with high urine measures also had high seated plasma metanephrines in the absence of PPGL. Properly prepared and collected supine plasma metanephrines had a false-positive rate of <3% in the absence of known PPGL/adrenal mass.

Pheochromocytoma-related cardiomyopathy presenting as acute myocardial infarction: A case report.

INTRODUCTION: Pheochromocytoma (PHEO)-related cardiomyopathy is a rare condition in which release of a large amount of catecholamines leads to severe vasoconstriction, coronary vasospasm, myocardial ischemia, injury, and necrosis. Its clinical manifestations can be similar to those of acute coronary syndrome. PATIENT CONCERNS: A 63-year-old woman was diagnosed with acute non-ST segment elevation myocardial infarction following chest pain for 8 hours. The results of coronary angiography were normal. The patient developed dyspnea, cough with frothy pink sputum, paroxysmal sweating, arrhythmia, and blood pressure fluctuation, and was transferred to the intensive care unit for monitoring and treatment. DIAGNOSIS: PHEO, catecholamine cardiomyopathy (CICMP). INTERVENTION: After monitoring the pulse index continuous cardiac output and treatment with α and ß adrenergic receptor blockers for 18 days, laparoscopic resection of the left adrenal mass was performed. OUTCOMES: The patient's condition improved and she was discharged 31 days after admission. Outpatient follow-up examinations 1 month and 1 year later did not show recurrence. LESSONS: PHEO can cause CICMP, the manifestations of which are partly similar to those of takotsubo cardiomyopathy (TTC). Once the patient's condition stabilizes, surgery should be considered. Fluid management is necessary, and agents such as α and ß adrenergic receptor blockers should be administered.

Intrarenal hemodynamics and kidney function in pheochromocytoma and paraganglioma before and after surgical treatment.

PURPOSE: Current evidence regarding renal involvement in pheochromocytoma and paraganglioma (PPGL) is scant. More accurate diagnostic methods, such as renal Doppler ultrasound for intrarenal hemodynamic studies, may provide more detailed information on renal function. It might be postulated that renal function in PPGL patients might be altered by high blood pressure and excess secretion of catecholamines. The aim of this prospective study was to assess intrarenal blood flow parameters in PPGL patients included in the prospective monoamine-producing tumour (PMT) study and to evaluate the effects of normalisation of catecholamine production after surgical treatment on long-term renal function. MATERIALS AND METHODS: Seventy consecutive patients (aged 46.5 ± 14.0 years) with PPGL were included. Forty-eight patients from the PMT study cohort, matched for age, gender, blood pressure level and presence of hypertension, served as a control group. Renal artery doppler ultrasound spectral analysis included mean resistance index (RRI) and pulsatility index (PI). Forty-seven patients completed 12 months follow-up. RESULTS: There were no differences in renal parameters such as RRI, PI and kidney function between PPGL and non-PPGL patients as assessed by renal ultrasound, serum creatinine, eGFR and albumin excretion rate. No correlations between kidney function parameters, intrarenal doppler flow parameters and plasma catecholamines were observed in PPGL patients. At 12 months after surgery, no differences in creatinine level, eGFR, albumin excretion rate, RI and PI were found as compared to baseline results. CONCLUSIONS: In contrast to patients with other forms of secondary hypertension, our study did not show differences in intrarenal blood flow parameters and renal function between PPGL and non-PPGL subjects. Intrarenal hemodynamics and renal function did not change after normalisation of catecholamine levels by surgical treatment.

Abdominal pain with intra-adrenal bleeding as an initial presentation of pheochromocytoma.

A 55-year-old man presented with severe right upper quadrant abdominal pain and hypertension up to 231/171 mm Hg on a background of a known adrenal mass, intravenous drug use and recurrent anxiety attacks. CT showed heterogenous lesion of the right adrenal gland but the sudden severe pain remained unexplained. After correction of the blood pressure with analgesia and antihypertensives, the patient developed a type 2 non-ST-elevation myocardial infarction that was treated with aspirin and therapeutic enoxaparin. This resulted in worsening pain and a repeat CT angiogram showed a haemoretroperitoneum around the right adrenal lesion. On review, an occult intra-adrenal haemorrhage was identified on the initial CT scan. Presumably this concealed haemorrhage caused the initial pain crisis and later decompressed into the retroperitoneal space. Raised metanephrine levels confirmed the diagnosis of pheochromocytoma and after preoperative optimisation with phenoxybenzamine, an open right adrenalectomy was performed.

Discrepancies in the Recommended Management of Adrenal Incidentalomas by Various Guidelines.

PURPOSE: Adrenal incidentalomas are being discovered with increasing frequency, and their discovery poses a challenge to clinicians. Despite the 2002 National Institutes of Health consensus statement, there are still discrepancies in the most recent guidelines from organizations representing endocrinology, endocrine surgery, urology and radiology. We review recent guidelines across the specialties involved in diagnosing and treating adrenal incidentalomas, and discuss points of agreement as well as controversy among guidelines. MATERIALS AND METHODS: PubMed®, Scopus®, Embase™ and Web of Science™ databases were searched systematically in November 2019 in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement to identify the most recently updated committee produced clinical guidelines in each of the 4 specialties. Five articles met the inclusion criteria. RESULTS: There is little debate among the reviewed guidelines as to the initial evaluation of an adrenal incidentaloma. All patients with a newly discovered adrenal incidentaloma should receive an unenhanced computerized tomogram and hormone screen. The most significant points of divergence among the guidelines regard reimaging an initially benign appearing mass, repeat hormone testing and management of an adrenal incidentaloma that is not easily characterized as benign or malignant on computerized tomography. The guidelines range from actively recommending against any repeat imaging and hormone screening to recommending a repeat scan as early as in 3 to 6 months and annual hormonal screening for several years. CONCLUSIONS: After reviewing the guidelines and the evidence used to support them we posit that best practices lie at their convergence and have presented our management recommendations on how to navigate the guidelines when they are discrepant.