Belzutifan, a Potent HIF2α Inhibitor, in the Pacak-Zhuang Syndrome.

The integration of genomic testing into clinical care enables the use of individualized approaches to the management of rare diseases. We describe the use of belzutifan, a potent and selective small-molecule inhibitor of the protein hypoxia-inducible factor 2α (HIF2α), in a patient with polycythemia and multiple paragangliomas (the Pacak-Zhuang syndrome). The syndrome was caused in this patient by somatic mosaicism for an activating mutation in EPAS1. Treatment with belzutifan led to a rapid and sustained tumor response along with resolution of hypertension, headaches, and long-standing polycythemia. This case shows the application of a targeted therapy for the treatment of a patient with a rare tumor-predisposition syndrome. (Funded by the Morin Family Fund for Pediatric Cancer and Alex's Lemonade Stand Foundation.).

Association between excess catecholamine synthesis and polymorphic premature ventricular contraction.

BACKGROUND: The reasons for the etiology of premature ventricular contractions (PVCs) are not specifically known. Many patients are resistant to medical treatment, and a factor that would predict response to medical treatment cannot be identified. This study aims to investigate if a high catecholamine level results in polymorphic PVC. METHODS: This study was obtained by prospective data registry analysis. A total of 100 patients, 50 from the PVC group, and 50 from the control group have been evaluated. The participants who were included in the patient group had a polymorphic PVC of 5% or more in their 24-h Holter evaluations. Metanephrine showing the level of adrenaline and normetanephrine, showing the level of noradrenaline levels have been measured from these urine samples. RESULT: There was no difference between the two groups in terms of biochemical and essential characteristics. Normetanephrine level has been significantly higher in the PVC group compared to the control group (323.9 ± 208.9 µg to 129.25 ± 67.88 µg; p < 0.001). Similarly, metanephrine level has also been higher in the PVC group (124.75 ± 82.43 µg to 52.615 ± 36,54 µg; p < 0.001). A positive and moderate correlation has been identified between the number and ratio of PVC and the metanephrine and normetanephrine levels. CONCLUSION: In this study, we found that the catecholamine levels were higher in the polymorphic PVC group than in the healthy volunteers. Also, an increase in the number and rate of PVC has been observed as the catecholamine levels increased. CLINICAL TRIAL REGISTRATION: Urine Levels of Metanephrine and Normetanephrine in Patients With Frequent PVC; ClinicalTrials.gov number NCT03447002.

Correlation between the size of pheochromocytoma and the level of metanephrines.

Objective. Pheochromocytomas (PHEO) and paraganglioma (PGLs) are rare neuroendocrine catecholamine-producing tumors that arise from the chromaffin cells of either the adrenal medulla or extra-adrenal paraganglionic tissues. Despite the recent advances in imaging technologies, biochemical evidence of excessive catecholamine production by the tumor is considered the most important test for the diagnosis of these tumors. The aim of the present study is to investigate the role of the catecholamine metabolites (normetanephrine and metanephrine) levels in the diagnosis of PHEO/PGLs and to evaluate if their levels correlate with the size of these tumors. Patients and Methods. Twenty-five patients were included in the study during the time period of 10 years. Their data were compared with another set of 25 patients to obtain the sensitivity and specificity of metanephrine and normetanephrine in the diagnosis of PHEO/PGLs. The tumor size was reviewed in every patient to obtain the correlation coefficient between the tumor sizes and the plasma/24-hour urinary metanephrine levels. Results. The sensitivity and specificity rates for plasma metanephrine were 80-92% and 92-96%, respectively; while for 24-hour urinary metanephrine were 80-90% and 95-100%, respectively. We found a strong positive relationship between the tumor size and the plasma levels of normetanephrine (r=0.518, p<0.01), and metanephrine (r=0.577, p<0.01). While the relation with the 24-hour urinary concentrations of normetanephrine (r=0.384, p=0.01) and 24-h urinary meta-nephrine (r=0.138, p<0.01) was low. Conclusion. The determination of plasma and 24-hour urinary levels of metanephrines is a reliable test for the diagnosis of PHEO, as they are continuously produced by the tumor cells in contrast to catecholamines.

Hemodynamic parameters in patients undergoing surgery for pheochromocytoma/paraganglioma: a retrospective study.

BACKGROUND: Pheochromocytoma (PHEO) and paraganglioma (PGL) are rare neuroendocrine tumors characterized by hemodynamic instability, caused by the paroxysmal release of catecholamines. Patients may develop cardiovascular complications in the perioperative phase due to the massive release of catecholamines, particularly during anesthetic induction and surgical manipulation of the tumor. The aim of this retrospective study was to evaluate the risk factors involved in perioperative hemodynamic instability in patients who underwent surgery for chromaffin tumors. METHODS: Forty patients (median age 55 [36.50-64.50]) undergone surgery for PHEO/abdominal PGL from January 2011 to December 2016 at the AOU Careggi (Florence, Italy) were retrospectively evaluated. Systolic, diastolic, and mean blood pressure were considered at baseline and during surgery. Patients with blood pressure steadily < 140/90 mmHg before surgery were considered "adequately prepared". A preoperative therapy with doxazosin, a selective alpha-1 blocker, was started in all patients for at least 14 days prior to the surgery. The presence of hemodynamic instability was reported. RESULTS: Comparing males and females, a significant difference in doxazosin daily dose (p = 0.018), systolic blood pressure (p = 0.048), and in the proportion of adequately prepared patients (p = 0.031) emerged. A positive correlation between preoperative daily dose of doxazosin, tumor size (B = 0.60, p < 0.001), and urinary normetanephrine levels (B = 0.64, p < 0.001) was also observed. Hemodynamic instability occurred in 30.0% of patients. The absence of adequate preparation (p = 0.012) before surgery, urinary normetanephrine levels (NMNur p = 0.039), and surgery time (minutes) (p = 0.021) resulted as risk factors of hemodynamic instability in our series. The use of intraoperative drugs was higher in patients with hemodynamic instability (p < 0.001). A pre-surgical SBP level of > 133 mmHg (OR = 6 CI95% 1.37-26.20, p = 0.017) and an intraoperative SBP and MBP levels of > 127 mmHg (OR = 28.80 CI95% 2.23-371.0, p = 0.010) and > 90 mmHg (OR = 18.90 CI95% 1.82-196.0, p = 0.014), respectively, were identified as effective thresholds to recognize patients at higher risk of HI. CONCLUSIONS: A preoperative therapy with alpha-blockers is useful, but not sufficient to avoid surgical risks. Patients with higher pre-surgical levels of NMNur, pre-surgical SBP > 133 mmHg, and/or intraoperative SBP > 127 mmHg and MBP > 90 mmHg, should be carefully monitored. A multidisciplinary approach is indispensable to optimize the management of PHEOs/abdominal PGLs in order to reduce surgical complications.

An adrenal cortical adenoma with neuroendocrine-type granules mimicking pheochromocytoma.

Clinical and biochemical presentation of adrenal tumors may rarely conflict with their histologic features. In the present report, we describe a rare case of adrenal neoplasm clinically and biochemically labeled as pheochromocytoma which at histologic examination resulted adrenal cortical tumor. The neoplasm was examined with the electron microscope which revealed the presence of electron-dense neuroendocrine-type granules next to intracytoplasmic lipid droplets. The patient underwent laparoscopic left adrenalectomy which leads to normalization of 24 h urinary metanephrine and normetanephrine. This exceptional entity should be taken into consideration when the clinical and laboratory features conflict with the histological examination. The pathologist can clarify the mixed nature of the tumor by means of the identification of neuroendocrine granules at the electron microscope examination.

Reliability of Biomarkers of Physiological Stress at Rest and Post-exertional Heat Stress.

The purpose of this study was to assess the reliability of blood biomarkers that can signify exercise-induced heat stress in hot conditions. Fourteen males completed two heat stress tests separated by 5-7 days. Venous blood was drawn pre- and post- heat stress for the concentration of normetanephrine, metanephrine, serum osmolality, copeptin, kidney-injury molecule 1, and neutrophil gelatinase-associated lipocalin. No biomarker, except copeptin, displayed systematic trial order bias (p≥0.05). Normetanephrine, copeptin and neutrophil gelatinase-associated lipocalin presented acceptable reliability (CV range: 0.9-14.3%), while greater variability was present in metanephrine, osmolality and kidney-injury molecule 1 (CV range: 28.6-43.2%). Normetanephrine exhibited the largest increase (p<0.001) in response to heat stress (trial 1=1048±461 pmol. L-1; trial 2=1067±408 pmol. L-1), whilst kidney-injury molecule 1 presented trivial changes (trial 1=-4±20 ng. L-1; trial 2=2 ± 16 ng. L-1, p>0.05). Normetanephrine, copeptin, and neutrophil gelatinase-associated lipocalin demonstrated good reliability and sensitivity to an acute bout of heat stress. These biomarkers may be suitable for application in laboratory and field research to understand the efficacy of interventions that can attenuate the risk of thermal injury whilst exercising in the heat.

Clonidine suppression test for a reliable diagnosis of pheochromocytoma: When to use.

OBJECTIVE: In clinical practice, false-positive results in biochemical testing for suspected pheochromocytoma/paraganglioma (PPGL) are not infrequent and may lead to unnecessary examinations. We aimed to evaluate the role of the clonidine suppression test (CST) in the era of analyses of plasma-free metanephrines for the diagnosis or exclusion of PPGL in patients with adrenal tumours and/or arterial hypertension. DESIGN AND METHODS: This single-centre, prospective trial investigated the use of CST in 60 patients with suspected PPGL associated with out-patient elevations of plasma normetanephrine (NMN) and/or metanephrine (MN), in most cases accompanied with hypertension or an adrenal mass. Measurements of plasma catecholamines and free metanephrines were performed by liquid chromatography with electrochemical detection and tandem mass spectrometry, respectively. RESULTS: Forty-six patients entered final analysis (n = 20 with PPGL and n = 26 with a nonfunctional adrenal mass and/or hypertension). CST reliably excluded false-positive baseline NMN results with a specificity of 100%. The sensitivity of CST improved from 85% to 94% when tumours with isolated MN increase (n = 3) were not considered. In patients with elevated baseline NMN (n = 24), CST correctly identified all patients without PPGL. Patients with falsely elevated baseline NMN results (n = 7, 26.9%) exhibited increases of baseline NMN up to 1.7-fold above the upper reference limit. CONCLUSION: CST qualifies as a useful diagnostic tool for differential diagnosis of borderline elevated plasma-free NMN in patients with suspected PPGL. In this context, CST helps to correctly identify all false-positive NMN screening results.

Application of Metanephrine and Normetanephrine in Evaluating the Selectivity of Adrenal Vein Sampling.

The aim of the study was to investigate the usefulness of metanephrine (MN) and normetanephrine (NMN) in bilateral simultaneous adrenal vein sampling (AVS) with and without ACTH stimulation. The study was conducted in a single referral center. Prospective recruited patients with PA were treated with AVS. The effects of cortisol, MN and NMN on selectivity catheterization were assessed and determined by lateralization. We enrolled 54 patients with PA who were treated with simultaneous bilateral AVS with ACTH. The Selectivity Index (SI) calculated by MN was higher than that calculated by other indicators (p<0.001), the catheterization success rate of MN at baseline was the same as that of cortisol after ACTH stimulation, and in lateralization diagnosis, MN was not inferior to cortisol. In conclusion, among the studied indicators, MN is the best index for determining the catheterization selectivity in AVS, especially in the absence of ACTH stimulation.

An automated magnetic bead extraction method for measuring plasma metanephrines and 3-methoxytyramine using liquid chromatography tandem mass spectrometry.

Liquid chromatography tandem mass spectrometry (LC-MS/MS) is used routinely in clinical diagnostics; however, automating the sample pretreatment is challenging. We established and evaluated an automated method based on the magnetic bead extraction principle (MBE) to measure normetanephrine (NMN), metanephrine (MN), and 3-methoxytyramine (3-MT). The target analytes were extracted, purified, and concentrated using different solvents and chemical bond-modified magnetic beads transferred via a magnetic bar. The linearity, recovery, matrix effect, and precision of MBE were evaluated thoroughly, and compared with traditional solid-phase extraction (SPE) using 131 plasma samples. The chromatography peaks of metanephrines and 3-MT, extracted via MBE, are symmetrical, without interfering peaks. The linearity was excellent with correlation coefficient (r) > 0.99. The MBE exhibited good reproducibility with within-run coefficient variations (CVs) of 1.96-2.00%, 4.06-5.75%, and 3.89-4.90% for MN, NMN, and 3-MT, respectively. The total CVs for MN, NMN, and 3-MT were 1.96-2.80%, 5.12-5.75%, and 5.44-6.27%, respectively. The relative recoveries for MN, NMN, and 3-MT varied between 93.5 and 107.4%, whereas their biases were all within 10%. The results for MN, NMN, and 3-MT extracted via MBE compared with SPE exhibited excellent correlation, with r > 0.99; the mean bias% for MN, NMN, and 3-MT were small (-2.9%, -3.2%, and -3.2%, respectively). In conclusion, the automated MBE method for measuring plasma metanephrines and 3-MT can be applied in future routine clinical diagnostics, and the MBE principle may indicate a new era for LC-MS/MS in clinical application.

The effect of acid use as a preservative on the results of biochemical tests measured in 24-h urine.

Twenty-four-hour urine measurements play a crucial role in the diagnosis, follow-up and treatment of various diseases. There are different approaches to the collection of urine in patients who need to collect multiple urine samples at a time, especially in hospitals with heavy workloads. In this study, we compared the sodium, potassium, chloride, amylase, calcium, creatinine, phosphorus, microalbumin, protein, magnesium, urea, uric acid, adrenaline, noradrenaline, dopamine, metanephrine, normetanephrine, vanillylmandelic acid, 5-hydroxyindoleacetic acid and homovanillic acid results of 24-h urine samples analyzed immediately without acid addition, which we accepted as the reference and baseline measurement, with the results of the samples analyzed after waiting for 24 h without acid addition, analyzed immediately with acid addition and analyzed after waiting for 24 h with acid addition. Chloride, microalbumin, amylase and protein tests, which are recommended to be measured in the sample without preservatives, are affected by acid addition. Adrenaline, noradrenaline and dopamine, which are the tests recommended to be measured in acid-added urine are degraded in the samples without acid, and the levels of metanephrine and normetanephrine were not significantly degraded in the absence of preservatives.

Bromocriptine-QR Therapy Reduces Sympathetic Tone and Ameliorates a Pro-Oxidative/Pro-Inflammatory Phenotype in Peripheral Blood Mononuclear Cells and Plasma of Type 2 Diabetes Subjects.

Bromocriptine-QR is a sympatholytic dopamine D2 agonist for the treatment of type 2 diabetes that has demonstrated rapid (within 1 year) substantial reductions in adverse cardiovascular events in this population by as yet incompletely delineated mechanisms. However, a chronic state of elevated sympathetic nervous system activity and central hypodopaminergic function has been demonstrated to potentiate an immune system pro-oxidative/pro-inflammatory condition and this immune phenotype is known to contribute significantly to the advancement of cardiovascular disease (CVD). Therefore, the possibility exists that bromocriptine-QR therapy may reduce adverse cardiovascular events in type 2 diabetes subjects via attenuation of this underlying chronic pro-oxidative/pro-inflammatory state. The present study was undertaken to assess the impact of bromocriptine-QR on a wide range of immune pro-oxidative/pro-inflammatory biochemical pathways and genes known to be operative in the genesis and progression of CVD. Inflammatory peripheral blood mononuclear cell biology is both a significant contributor to cardiovascular disease and also a marker of the body's systemic pro-inflammatory status. Therefore, this study investigated the effects of 4-month circadian-timed (within 2 h of waking in the morning) bromocriptine-QR therapy (3.2 mg/day) in type 2 diabetes subjects whose glycemia was not optimally controlled on the glucagon-like peptide 1 receptor agonist on (i) gene expression status (via qPCR) of a wide array of mononuclear cell pro-oxidative/pro-inflammatory genes known to participate in the genesis and progression of CVD (OXR1, NRF2, NQO1, SOD1, SOD2, CAT, GSR, GPX1, GPX4, GCH1, HMOX1, BiP, EIF2α, ATF4, PERK, XBP1, ATF6, CHOP, GSK3ß, NFkB, TXNIP, PIN1, BECN1, TLR2, TLR4, TLR10, MAPK8, NLRP3, CCR2, GCR, L-selectin, VCAM1, ICAM1) and (ii) humoral measures of sympathetic tone (norepinephrine and normetanephrine), whole-body oxidative stress (nitrotyrosine, TBARS), and pro-inflammatory factors (IL-1ß, IL-6, IL-18, MCP-1, prolactin, C-reactive protein [CRP]). Relative to pre-treatment status, 4 months of bromocriptine-QR therapy resulted in significant reductions of mRNA levels in PBMC endoplasmic reticulum stress-unfolded protein response effectors [GRP78/BiP (34%), EIF2α (32%), ATF4 (29%), XBP1 (25%), PIN1 (14%), BECN1 (23%)], oxidative stress response proteins [OXR1 (31%), NRF2 (32%), NQO1 (39%), SOD1 (52%), CAT (26%), GPX1 (33%), GPX4 (31%), GCH1 (30%), HMOX1 (40%)], mRNA levels of TLR pro-inflammatory pathway proteins [TLR2 (46%), TLR4 (20%), GSK3ß (19%), NFkB (33%), TXNIP (18%), NLRP3 (32%), CCR2 (24%), GCR (28%)], mRNA levels of pro-inflammatory cellular receptor proteins CCR2 and GCR by 24% and 28%, and adhesion molecule proteins L-selectin (35%) and VCAM1 (24%). Relative to baseline, bromocriptine-QR therapy also significantly reduced plasma levels of norepinephrine and normetanephrine by 33% and 22%, respectively, plasma pro-oxidative markers nitrotyrosine and TBARS by 13% and 10%, respectively, and pro-inflammatory factors IL-18, MCP1, IL-1ß, prolactin, and CRP by 21%,13%, 12%, 42%, and 45%, respectively. These findings suggest a unique role for circadian-timed bromocriptine-QR sympatholytic dopamine agonist therapy in reducing systemic low-grade sterile inflammation to thereby reduce cardiovascular disease risk.

Dual-Template Magnetic Molecularly Imprinted Polymer for Simultaneous Determination of Spot Urine Metanephrines and 3-Methoxytyramine for the Diagnosis of Pheochromocytomas and Paragangliomas.

A novel dual-template magnetic molecularly imprinted polymer (MMIP) was synthesized to extract normetanephrine (NMN), metanephrine (MN) and 3-methoxytyramine (3-MT) from spot urine samples. As the adsorbent of dispersive solid-phase extraction (d-SPE), the MMIP was prepared using dopamine and MN as dual templates, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the crosslinking reagent and magnetic nanoparticles as the magnetic core. NMN, MN, 3-MT and creatinine (Cr) in spot urine samples were selectively enriched by d-SPE and detected by HPLC-fluorescence detection/ultraviolet detection. The peak area (A) ratios of NMN, MN and 3-MT to Cr were used for the diagnosis of pheochromocytomas and paragangliomas (PPGLs). The results showed that the adsorption efficiencies of MMIP for target analytes were all higher than 89.0%, and the coefficient variation precisions of intra-assay and inter-assay for the analytes were within 4.9% and 6.3%, respectively. The recoveries of the analytes were from 93.2% to 112.8%. The MMIP was still functional within 14 days and could be reused at least seven times. The d-SPE and recommended solid-phase extraction (SPE) were both used to pretreat spot urine samples from 18 PPGLs patients and 22 healthy controls. The correlation coefficients of ANMN/ACr and AMN/ACr between d-SPE and SPE were both higher than 0.95. In addition, the areas under the receiver operator curves for spot urine ANMN/ACr, AMN/ACr and plasma free NMN and MN were 0.975, 0.773 and 0.990, 0.821, respectively, indicating the two methods had the similar performances. The d-SPE method took only 20 min, which was effective in clinical application.

Harmonization of LC-MS/MS Measurements of Plasma Free Normetanephrine, Metanephrine, and 3-Methoxytyramine.

BACKGROUND: Plasma-free normetanephrine and metanephrine (metanephrines) are the recommended biomarkers for testing of pheochromocytoma and paraganglioma (PPGL). This study evaluated the status of harmonization of liquid chromatography-tandem mass spectrometry-based measurements of plasma metanephrines and methoxytyramine and clinical interpretation of test results. METHODS: 125 plasma samples from patients tested for PPGLs were analyzed in 12 laboratories. Analytical performance was also assessed from results of a proficiency-testing program. Agreement of test results from different laboratories was assessed by Passing-Bablok regression and Bland-Altman analysis. Agreement in clinical test interpretation based on laboratory specific reference intervals was also examined. RESULTS: Comparisons of analytical test results by regression analysis revealed strong correlations for normetanephrine and metanephrine (R ≥ 0.95) with mean slopes of 1.013 (range 0.975-1.078), and 1.019 (range 0.963-1.081), and intercepts of -0.584 (-53.736 to 54.790) and -3.194 (-17.152 to 5.933), respectively. The mean bias between methods was 1.2% (-11.6% to 16.0%) for metanephrine and 0.1% (-18.0% to 9.5%) for normetanephrine. Measurements of 3-methoxytyramine revealed suboptimal agreement between laboratories with biases ranging from -32.2% to 64.0%. Interrater agreement in test interpretation was >94% for metanephrine and >84% for normetanephrine; improvements in interrater agreement were observed with use of harmonized reference intervals, including age-specific cut-offs for normetanephrine. CONCLUSIONS: Analytical methods for metanephrines are well harmonized between laboratories. However, the 16% disagreement in test interpretation for normetanephrine suggests use of suboptimal method-dependent reference intervals for clinical decision-making for this metabolite. Improved analytical methods and reference interval harmonization are particularly required for 3-methoxytyramine.

Diagnostic Accuracy of Salivary Metanephrines in Pheochromocytomas and Paragangliomas.

BACKGROUND: Measurements of plasma free metanephrines are recommended for diagnosing pheochromocytomas and paragangliomas (PPGL). Metanephrines can be detected in saliva with LC-MS/MS with sufficient analytical sensitivity and precision. Because collecting saliva is noninvasive and less cumbersome than plasma or urine sampling, we assessed the diagnostic accuracy of salivary metanephrines in diagnosing PPGL. METHODS: This 2-center study included 118 healthy participants (44 men; mean age: 33 years (range: 19--74 years)), 44 patients with PPGL, and 54 patients suspected of PPGL. Metanephrines were quantified in plasma and saliva using LC-MS/MS. Diagnostic accuracy; correlation between plasma and salivary metanephrines; and potential factors influencing salivary metanephrines, including age, sex, and posture during sampling, were assessed. RESULTS: Salivary metanephrines were significantly higher in patients with PPGL compared with healthy participants (metanephrine (MN): 0.19 vs 0.09 nmol/L, P < 0.001; normetanephrine (NMN): 2.90 vs 0.49 nmol/L, P < 0.001). The diagnostic sensitivity and specificity of salivary metanephrines were 89% and 87%, respectively. Diagnostic accuracy of salivary metanephrines was 88%, with an area under the ROC curve of 0.880. We found a significant correlation between plasma and salivary metanephrines (Pearson correlation coefficient: MN, 0.86, P < 0.001; NMN, 0.83, P < 0.001). Salivary NMN concentrations were higher when collected in a seated position compared with supine (P < 0.001) and increased with age (P < 0.001). CONCLUSIONS: Salivary metanephrines are a promising tool in the biochemical diagnosis of PPGL. Salivary metanephrines correlate with plasma free metanephrines and are increased in patients with PPGL. At this time, however, salivary metanephrines cannot replace measurement of plasma free metanephrines.

Solitary vaginal paraganglioma with mature sacrococcygeal teratoma: a rare case report.

BACKGROUND: Vaginal paraganglioma are rare, atypical, solitary tumors which originate from the female genital tract. Sacrococcygeal teratoma are also rare neoplasms which derive from one (or more) primordial germ cell layers. Here we report a unique case of vaginal paraganglioma with sacrococcygeal teratoma. CASE PRESENTATION: A 44-year-old female experienced paroxysmal hypertension, palpitations and dizziness for almost six years. Enhanced CT and MRI highlighted two abnormal soft tissue lesions located in the left vaginal wall and coccyx anteriorly, and Iodine-131 metaiodobenzylguanidine (131I-MIBG) demonstrated abnormal radioactive uptake in perineum area. Endocrine tests showed elevated plasma normetanephrine (NMN) and 24 h urine norepinephrine. There was a well-circumscribed soft tissue lesion of approximately 3.5 cm in the left lateral vaginal wall which could be palpated during bimanual examination, together with a 1.5 cm tumor in the posterior wall of the rectum. We completely resected the two lesions in stages with the support of a senior gynecologist and general surgeons. Postoperative histopathological examinations suggested the vaginal paraganglioma and mature sacrococcygeal teratoma. Targeted sanger sequencing for the 36 mostly common paraganglioma-related genes, with a depth of 1000x, revealed no mutations. Post-operatively, plasma NMN and 24 h urine norepinephrine returned to the normal range and her symptoms completely disappeared. CONCLUSIONS: We reported an extremely rare case and the successful treatment of functional vaginal paraganglioma coexisting with adult sacrococcygeal teratoma.

Plasma or serum, which is the better choice for the measurement of metanephrines?

Measurement of metanephrines (MNs: metanephrine [MN] and normetanephrine [NMN]) is recommended for the initial biochemical diagnosis of pheochromocytoma and paraganglioma. Despite some drawbacks, plasma is commonly used for sampling. Here, we determined the feasibility of using serum, as an alternative to plasma, by comparing MNs in plasma and serum and evaluating the stability of MNs in serum. MNs obtained from serum, EDTA plasma, and heparin plasma were measured using LC-MS/MS immediately or after storage at 4 °C for 24 h, 72 h, and 7 days, and at -80 °C for 7 days, after sample collection. The differences between sample stability at given time points were compared using one-way ANOVA and Students' paired t-test, and the mean percent deviation was compared with total change limit (TCL). No significant difference was observed in MN and NMN between serum and EDTA plasma, and the mean percent deviation of the results obtained from serum compared to that from EDTA plasma was within the TCL. However, the difference of MN between EDTA plasma and heparin plasma exceeded the TCL. Both MNs in EDTA plasma and heparin plasma showed a significant decreasing trend at 4 °C with time (p < .01), while those in serum were relatively stable, with the mean percent deviation not exceeding the TCL at any time point or temperature. In conclusion, MNs measurement did not significantly differ between EDTA plasma and serum when measured immediately after collection, and MNs in serum were more stable than that in plasma.

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.

Predictors of Hypotension after Adrenalectomy for Pheochromocytoma.

The management of blood pressure is a significant concern for surgeons and anesthesiologists performing adrenalectomy for pheochromocytoma. We evaluated clinical factors in pheochromocytoma patients to identify the predictors of postoperative hypotension. The medical records of patients who underwent adrenalectomy for pheochromocytoma between 2001 and 2017 were retrospectively reviewed and clinical and biochemical data were evaluated. Of 29 patients, 13 patients needed catecholamine support in the perisurgical period while 16 patients did not. There were significant differences in median age, tumor size, and blood pressure drop (maxmin) between the 2 groups (68 vs 53 years old, p=0.045; 50 vs 32 mm diameter, p=0.022; 110 vs 71 mmHg, p=0.015 respectively). In univariate logistic analysis, age > 65.5 years, tumor size > 34.5 mm, urine metanephrine > 0.205 mg/day and urine normetanephrine > 0.665 mg/day were significant predictors of prolonged hypotension requiring postoperative catecholamine support. Tumor size and urine metanephrine and urine normetanephrine levels were correlated with postoperative hypotension. These predictors may help in the safe perioperative management of pheochromocytoma patients treated with adrenalectomy.

Assessment of Epinephrine and Norepinephrine in Gastric Carcinoma.

The aim of our study was to assess the sympathetic nervous system's involvement in the evolution of gastric carcinoma in patients by analyzing the mediators of this system (epinephrine and norepinephrine), as well as by analyzing the histological expression of the norepinephrine transporter (NET). We conducted an observational study including 91 patients diagnosed with gastric carcinoma and an additional 200 patients without cancer between November 2017 and October 2018. We set the primary endpoint as mortality from any cause in the first two years after enrolment in the study. The patients were monitored by a 24-h Holter electrocardiogram (ECG) to assess sympathetic or parasympathetic predominance. Blood was also collected from the patients to measure plasma free metanephrine (Meta) and normetanephrine (N-Meta), and tumor histological samples were collected for the analysis of NET expression. All of this was performed prior to the application of any antineoplastic therapy. Each patient was monitored for two years. We found higher heart rates in patients with gastric carcinoma than those without cancer. Regarding Meta and N-Meta, elevated levels were recorded in the patients with gastric carcinoma, correlating with the degree of tumor differentiation and other negative prognostic factors such as tumor invasion, lymph node metastasis, and distant metastases. Elevated Meta and N-Meta was also associated with a poor survival rate. All these data suggest that the predominance of the sympathetic nervous system's activity predicts increased gastric carcinoma severity.

Neurochemical Effects of 4-(2Chloro-4-Fluorobenzyl)-3-(2-Thienyl)-1,2,4-Oxadiazol-5(4H)-One in the Pentylenetetrazole (PTZ)-Induced Epileptic Seizure Zebrafish Model.

Epilepsy is one of the most common neurological disorders, and it is characterized by spontaneous seizures. In a previous study, we identified 4-(2-chloro-4-fluorobenzyl)-3-(2-thienyl)-1,2,4-oxadiazol-5(4H)-one (GM-90432) as a novel anti-epileptic agent in chemically- or genetically-induced epileptic zebrafish and mouse models. In this study, we investigated the anti-epileptic effects of GM-90432 through neurochemical profiling-based approach to understand the neuroprotective mechanism in a pentylenetetrazole (PTZ)-induced epileptic seizure zebrafish model. GM-90432 effectively improved PTZ-induced epileptic behaviors via upregulation of 5-hydroxytryptamine, 17-ß-estradiol, dihydrotestosterone, progesterone, 5α -dihydroprogesterone, and allopregnanolone levels, and downregulation of normetanephrine, gamma-aminobutyric acid, and cortisol levels in brain tissue. GM-90432 also had a protective effect against PTZ-induced oxidative stress and zebrafish death, suggesting that it exhibits biphasic neuroprotective effects via scavenging of reactive oxygen species and anti-epileptic activities in a zebrafish model. In conclusion, our results suggest that neurochemical profiling study could be used to better understand of anti-epileptic mechanism of GM-90432, potentially leading to new drug discovery and development of anti-seizure agents.