International consensus statement on the diagnosis and management of phaeochromocytoma and paraganglioma in children and adolescents.

Phaeochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumours that arise not only in adulthood but also in childhood and adolescence. Up to 70-80% of childhood PPGL are hereditary, accounting for a higher incidence of metastatic and/or multifocal PPGL in paediatric patients than in adult patients. Key differences in the tumour biology and management, together with rare disease incidence and therapeutic challenges in paediatric compared with adult patients, mandate close expert cross-disciplinary teamwork. Teams should ideally include adult and paediatric endocrinologists, oncologists, cardiologists, surgeons, geneticists, pathologists, radiologists, clinical psychologists and nuclear medicine physicians. Provision of an international Consensus Statement should improve care and outcomes for children and adolescents with these tumours.

Steroidomics-Based Screening for Primary Aldosteronism: Impact of antihypertensive Drugs.

BACKGROUND: Diagnosis of primary aldosteronism (PA) is complicated by the need to withdraw antihypertensive medications that interfere with test results, particularly renin. This study examined whether machine learning-based steroid-probability scores offer a renin measurement-independent approach for testing less prone to interference than the aldosterone-to-renin ratio (ARR). METHODS: This prospective multicenter cohort study involved the use of plasma steroidomics and the ARR in 839 patients tested for PA, including 190 with and 578 without PA (71 indeterminate). Receiver operating characteristic curves for steroid-probability scores and the ARR were examined with and without interfering medications. Impacts of individual medications on plasma aldosterone, 18-oxocortisol, 18-hydroxycortisol, steroid-probability scores, renin, and ARRs were examined by multivariable and paired analyses in patients with and without PA. RESULTS: Receiver operating characteristic curves indicated a significant impact of interfering antihypertensive medications on the diagnostic performance of the ARR and minimal impact on steroid-probability scores. Mineralocorticoid receptor antagonists increased plasma aldosterone, 18-oxocortisol, and 18-hydroxycortisol in patients without PA and resulted in false-positive test results for steroid-probability scores and false-negative results for the ARR. Diuretics increased aldosterone, 18-oxocortisol, and steroid-probability scores in patients without PA, whereas angiotensin-converting enzyme inhibitors decreased aldosterone, steroid-probability scores, and ARRs. Beta-adrenoceptor blockers, dihydropyridine calcium channel blockers, and angiotensin receptor blockers had negligible impact on mineralocorticoids and steroid-probability scores. CONCLUSIONS: Among antihypertensive drugs that impact plasma aldosterone, 18-oxocortisol, and 18-hydroxycortisol, mineralocorticoid receptor antagonists stood out as a cause of false-positive results for derived steroid-probability scores. Other antihypertensives have minimal or no impact, an advantage for use of steroid-probability scores over the ARR when those medications cannot be withdrawn. REGISTRATION: URL: https://drks.de/; Unique identifier: DRKS00017084.

Diagnosis and management of urinary bladder paragangliomas: A Sino-American-European retrospective observational study.

OBJECTIVE: Paragangliomas of the urinary bladder (UBPGLs) are rare neuroendocrine tumours and pose a diagnostic and surgical challenge. It remains unclear what factors contribute to a timely presurgical diagnosis. The purpose of this study is to identify factors contributing to missing the diagnosis of UBPGLs before surgery. DESIGN, PATIENTS AND MEASUREMENTS: A total of 73 patients from 11 centres in China, and 51 patients from 6 centres in Europe and 1 center in the United States were included. Clinical, surgical and genetic data were collected and compared in patients diagnosed before versus after surgery. Logistic regression analysis was used to identify clinical factors associated with initiation of presurgical biochemical testing. RESULTS: Among all patients, only 47.6% were diagnosed before surgery. These patients were younger (34.0 vs. 54.0 years, p < .001), had larger tumours (2.9 vs. 1.8 cm, p < .001), and more had a SDHB pathogenic variant (54.7% vs. 11.9%, p < .001) than those diagnosed after surgery. Patients with presurgical diagnosis presented with more micturition spells (39.7% vs. 15.9%, p = .003), hypertension (50.0% vs. 31.7%, p = .041) and catecholamine-related symptoms (37.9% vs. 17.5%, p = .012). Multivariable logistic analysis revealed that presence of younger age (<35 years, odds ratio [OR] = 6.47, p = .013), micturition spells (OR = 6.79, p = .007), hypertension (OR = 3.98, p = .011), and sweating (OR = 41.72, p = .013) increased the probability of initiating presurgical biochemical testing. CONCLUSIONS: Most patients with UBPGL are diagnosed after surgery. Young age, hypertension, micturition spells and sweating are clues in assisting to initiate early biochemical testing and thus may establish a timely presurgical diagnosis.

Patient-reported burden associated with pheochromocytoma/paraganglioma diagnosis.

Pheochromocytoma and paragangliomas (PPGLs) originate from the chromaffin cells of the adrenal medulla or neural crest progenitors outside the adrenal gland, respectively. The estimated annual incidence of PPGL is between 2.0 and 8.0/million adults. Minimal data exist on the impact of PPGL from the patient's perspective. Therefore, a survey was adapted from a previously published study on gastroenteropancreatic neuroendocrine tumors to explore the voice of patients with PPGL and learn ways to improve clinical care while understanding the current gaps to direct future research. A self-reported online survey was available to patients with PPGL and those with genetic predisposition even without PPGL from June to July 2022. Survey questions captured sociodemographic and clinical characteristics, the diagnostic workup, treatment and monitoring, quality and access to care, and financial impact. Here, we report the most relevant findings on patient experience of disease burden following diagnosis. A total of 270 people responded, the majority of whom were from the USA (79%), Caucasian (88%), and female (81%). The results of this survey highlight the burden of disease on a patient's daily life, resulting in moderate to severe financial distress, increased travel time to specialized facilities resulting in loss of work and wages, and significant delays in care. Respondents reported being unheard and unacknowledged. With a median time to diagnosis just over 2 years, the physical, mental, and emotional toll are substantial. Increasing access to PPGL specialists and centers could lead to faster diagnoses and better management, which may reduce the burden on both patients and healthcare centers.

Screening for Primary Aldosteronism by Mass Spectrometry Versus Immunoassay Measurements of Aldosterone: A Prospective Within-Patient Study.

BACKGROUND: Measurements of aldosterone by mass spectrometry are more accurate and less prone to interferences than immunoassay measurements, and may produce a more accurate aldosterone:renin ratio (ARR) when screening for primary aldosteronism (PA). METHODS: Differences in diagnostic performance of the ARR using mass spectrometry vs immunoassay measurements of aldosterone were examined in 710 patients screened for PA. PA was confirmed in 153 patients and excluded in 451 others. Disease classifications were not achieved in 106 patients. Areas under receiver-operating characteristic curves (AUROC) and other measures were used to compare diagnostic performance. RESULTS: Mass spectrometry-based measurements yielded lower plasma aldosterone concentrations than immunoassay measurements. For the ARR based on immunoassay measurements of aldosterone, AUROCs were slightly lower (P = 0.018) than those using mass spectrometry measurements (0.895 vs 0.906). The cutoff for the ARR to reach a sensitivity of 95% was 30 and 21.5 pmol/mU by respective immunoassay and mass spectrometry-based measurements, which corresponded to specificities of 57% for both. With data restricted to patients with unilateral PA, diagnostic sensitivities of 94% with specificities >81% could be achieved at cutoffs of 68 and 52 pmol/mU for respective immunoassay and mass spectrometry measurements. CONCLUSIONS: Mass spectrometry-based measurements of aldosterone for the ARR provide no clear diagnostic advantage over immunoassay-based measurements. Both approaches offer limited diagnostic accuracy for the ARR as a screening test. One solution is to employ the higher cutoffs to triage patients likely to have unilateral PA for further tests and possible adrenalectomy, while using the lower cutoffs to identify others for targeted medical therapy.German Clinical Trials Register ID: DRKS00017084.

Imaging of Pheochromocytomas and Paragangliomas.

Pheochromocytomas/paragangliomas are unique in their highly variable molecular landscape driven by genetic alterations, either germline or somatic. These mutations translate into different clusters with distinct tumor locations, biochemical/metabolomic features, tumor cell characteristics (eg, receptors, transporters), and disease course. Such tumor heterogeneity calls for different imaging strategies in order to provide proper diagnosis and follow-up. This also warrants selection of the most appropriate and locally available imaging modalities tailored to an individual patient based on consideration of many relevant factors including age, (anticipated) tumor location(s), size, and multifocality, underlying genotype, biochemical phenotype, chance of metastases, as well as the patient's personal preference and treatment goals. Anatomical imaging using computed tomography and magnetic resonance imaging and functional imaging using positron emission tomography and single photon emission computed tomography are currently a cornerstone in the evaluation of patients with pheochromocytomas/paragangliomas. In modern nuclear medicine practice, a multitude of radionuclides with relevance to diagnostic work-up and treatment planning (theranostics) is available, including radiolabeled metaiodobenzylguanidine, fluorodeoxyglucose, fluorodihydroxyphenylalanine, and somatostatin analogues. This review amalgamates up-to-date imaging guidelines, expert opinions, and recent discoveries. Based on the rich toolbox for anatomical and functional imaging that is currently available, we aim to define a customized approach in patients with (suspected) pheochromocytomas/paragangliomas from a practical clinical perspective. We provide imaging algorithms for different starting points for initial diagnostic work-up and course of the disease, including adrenal incidentaloma, established biochemical diagnosis, postsurgical follow-up, tumor screening in pathogenic variant carriers, staging and restaging of metastatic disease, theranostics, and response monitoring.

Plasma Metanephrines Yield Fewer False-Positive Results Than Urine Metanephrines in Patients With Obstructive Sleep Apnea.

CONTEXT: Obstructive sleep apnea (OSA) is associated with increased nocturnal sympathetic activity. In OSA patients, elevations in metanephrines may lead to false-positive tests when evaluating for pheochromocytoma or paraganglioma (PPGL). OBJECTIVE: To evaluate whether morning plasma metanephrines would lead to fewer false-positive results than 24-hour urinary metanephrines in OSA patients. METHODS: Patients undergoing polysomnography for suspected OSA were recruited. Plasma free and 24-hour urinary metanephrines were measured by HPLC-MS/MS. Patients with elevated levels had repeat measurements, abdominal imaging, and follow-up to diagnose or exclude a PPGL. RESULTS: Seventy-six patients completed polysomnography and biochemical testing; 68 (89.5%) patients had OSA, of whom 19 (27.9%) had elevated plasma and/or urinary metanephrines. On follow-up, one patient had a bladder paraganglioma, while PPGL was excluded in the remaining patients. OSA patients had more false-positive urinary metanephrines (17 of 67, 25.4%) than plasma metanephrines (2 of 67, 3.0%), P < .01, and this was more common in severe OSA (13 of 34, 38.2%), compared to moderate/mild OSA (4 of 33, 12.1%), P < .01. Both plasma and urinary metanephrines decreased after treatment with continuous positive airway pressure. On multivariable analysis, severe OSA, obesity, and family history of hypertension were positive predictors for false-positive urinary metanephrines in patients with suspected OSA. CONCLUSION: In OSA patients, plasma metanephrines are less likely to yield false-positive results for the diagnosis of PPGL than 24-hour urinary metanephrines. In patients with suspected OSA, obesity, or a family history of hypertension, plasma metanephrines may be the preferred first-line test to avoid unnecessary anxiety or follow-up.

Management of phaeochromocytoma and paraganglioma in patients with germline SDHB pathogenic variants: an international expert Consensus statement.

Adult and paediatric patients with pathogenic variants in the gene encoding succinate dehydrogenase (SDH) subunit B (SDHB) often have locally aggressive, recurrent or metastatic phaeochromocytomas and paragangliomas (PPGLs). Furthermore, SDHB PPGLs have the highest rates of disease-specific morbidity and mortality compared with other hereditary PPGLs. PPGLs with SDHB pathogenic variants are often less differentiated and do not produce substantial amounts of catecholamines (in some patients, they produce only dopamine) compared with other hereditary subtypes, which enables these tumours to grow subclinically for a long time. In addition, SDHB pathogenic variants support tumour growth through high levels of the oncometabolite succinate and other mechanisms related to cancer initiation and progression. As a result, pseudohypoxia and upregulation of genes related to the hypoxia signalling pathway occur, promoting the growth, migration, invasiveness and metastasis of cancer cells. These factors, along with a high rate of metastasis, support early surgical intervention and total resection of PPGLs, regardless of the tumour size. The treatment of metastases is challenging and relies on either local or systemic therapies, or sometimes both. This Consensus statement should help guide clinicians in the diagnosis and management of patients with SDHB PPGLs.

Catecholamine-induced hypertensive crises: current insights and management.

Phaeochromocytomas and paragangliomas (PPGLs) release catecholamines leading to catecholamine-induced hypertensive (CIH) crises, with blood pressure greater than or equal to 180/120 mm Hg. CIH crises can be complicated by tachyarrhythmias, hypotension, or life-threatening target organ damage while treatment remains undefined, often requiring co-management between endocrinologists and cardiologists. Furthermore, biochemical diagnosis of a PPGL as a cause of a CIH crisis can be difficult to identify or confounded by comorbid conditions, potentially resulting in misdiagnosis. Here, we combine relevant evidence, 60 years of collective clinical experience, insights derived from assessing over 2600 patients with PPGL, and supplementary outcomes from 100 patients (treated at the National Institutes of Health) with a CIH crisis to inform diagnosis and treatment of CIH crises. Recognising that disparities exist between availability, cost, and familiarity of various agents, flexible approaches are delineated allowing for customisation, given institutional availability and provider preference. A CIH crisis and its complications are readily treatable with available drugs, with effective intervention defining an avenue for mitigating consequent morbidity and mortality in patients with PPGL.

Prediction of metastatic pheochromocytoma and paraganglioma: a machine learning modelling study using data from a cross-sectional cohort.

BACKGROUND: Pheochromocytomas and paragangliomas have up to a 20% rate of metastatic disease that cannot be reliably predicted. This study prospectively assessed whether the dopamine metabolite, methoxytyramine, might predict metastatic disease, whether predictions might be improved using machine learning models that incorporate other features, and how machine learning-based predictions compare with predictions made by specialists in the field. METHODS: In this machine learning modelling study, we used cross-sectional cohort data from the PMT trial, based in Germany, Poland, and the Netherlands, to prospectively examine the utility of methoxytyramine to predict metastatic disease in 267 patients with pheochromocytoma or paraganglioma and positive biochemical test results at initial screening. Another retrospective dataset of 493 patients with these tumors enrolled under clinical protocols at National Institutes of Health (00-CH-0093) and the Netherlands (PRESCRIPT trial) was used to train and validate machine learning models according to selections of additional features. The best performing machine learning models were then externally validated using data for all patients in the PMT trial. For comparison, 12 specialists provided predictions of metastatic disease using data from the training and external validation datasets. FINDINGS: Prospective predictions indicated that plasma methoxytyramine could identify metastatic disease at sensitivities of 52% and specificities of 85%. The best performing machine learning model was based on an ensemble tree classifier algorithm that used nine features: plasma methoxytyramine, metanephrine, normetanephrine, age, sex, previous history of pheochromocytoma or paraganglioma, location and size of primary tumours, and presence of multifocal disease. This model had an area under the receiver operating characteristic curve of 0·942 (95% CI 0·894-0·969) that was larger (p<0·0001) than that of the best performing specialist before (0·815, 0·778-0·853) and after (0·812, 0·781-0·854) provision of SDHB variant data. Sensitivity for prediction of metastatic disease in the external validation cohort reached 83% at a specificity of 92%. INTERPRETATION: Although methoxytyramine has some utility for prediction of metastatic pheochromocytomas and paragangliomas, sensitivity is limited. Predictive value is considerably enhanced with machine learning models that incorporate our nine recommended features. Our final model provides a preoperative approach to predict metastases in patients with pheochromocytomas and paragangliomas, and thereby guide individualised patient management and follow-up. FUNDING: Deutsche Forschungsgemeinschaft.

Clinical consensus guideline on the management of phaeochromocytoma and paraganglioma in patients harbouring germline SDHD pathogenic variants.

Patients with germline SDHD pathogenic variants (encoding succinate dehydrogenase subunit D; ie, paraganglioma 1 syndrome) are predominantly affected by head and neck paragangliomas, which, in almost 20% of patients, might coexist with paragangliomas arising from other locations (eg, adrenal medulla, para-aortic, cardiac or thoracic, and pelvic). Given the higher risk of tumour multifocality and bilaterality for phaeochromocytomas and paragangliomas (PPGLs) because of SDHD pathogenic variants than for their sporadic and other genotypic counterparts, the management of patients with SDHD PPGLs is clinically complex in terms of imaging, treatment, and management options. Furthermore, locally aggressive disease can be discovered at a young age or late in the disease course, which presents challenges in balancing surgical intervention with various medical and radiotherapeutic approaches. The axiom-first, do no harm-should always be considered and an initial period of observation (ie, watchful waiting) is often appropriate to characterise tumour behaviour in patients with these pathogenic variants. These patients should be referred to specialised high-volume medical centres. This consensus guideline aims to help physicians with the clinical decision-making process when caring for patients with SDHD PPGLs.

Biochemical Assessment of Pheochromocytoma and Paraganglioma.

Pheochromocytoma and paraganglioma (PPGL) require prompt consideration and efficient diagnosis and treatment to minimize associated morbidity and mortality. Once considered, appropriate biochemical testing is key to diagnosis. Advances in understanding catecholamine metabolism have clarified why measurements of the O-methylated catecholamine metabolites rather than the catecholamines themselves are important for effective diagnosis. These metabolites, normetanephrine and metanephrine, produced respectively from norepinephrine and epinephrine, can be measured in plasma or urine, with choice according to available methods or presentation of patients. For patients with signs and symptoms of catecholamine excess, either test will invariably establish the diagnosis, whereas the plasma test provides higher sensitivity than urinary metanephrines for patients screened due to an incidentaloma or genetic predisposition, particularly for small tumors or in patients with an asymptomatic presentation. Additional measurements of plasma methoxytyramine can be important for some tumors, such as paragangliomas, and for surveillance of patients at risk of metastatic disease. Avoidance of false-positive test results is best achieved by plasma measurements with appropriate reference intervals and preanalytical precautions, including sampling blood in the fully supine position. Follow-up of positive results, including optimization of preanalytics for repeat tests or whether to proceed directly to anatomic imaging or confirmatory clonidine tests, depends on the test results, which can also suggest likely size, adrenal vs extra-adrenal location, underlying biology, or even metastatic involvement of a suspected tumor. Modern biochemical testing now makes diagnosis of PPGL relatively simple. Integration of artificial intelligence into the process should make it possible to fine-tune these advances.

Recurrent Disease in Patients With Sporadic Pheochromocytoma and Paraganglioma.

CONTEXT: Long-term follow-up has been recommended for patients with pheochromocytoma or paraganglioma (PPGL) due to potential for recurrent disease. However, the need to follow patients with sporadic PPGL has recently become controversial. OBJECTIVE: To investigate the prevalence of recurrence among patients with sporadic compared with hereditary PPGL and to identify predictors of recurrence for sporadic disease. METHODS: This multicenter study included retrospective data from 1127 patients with PPGL. In addition to sex and age at primary tumor diagnosis, clinical information included location, size, and catecholamine phenotype of primary tumors, genetic test results, and subsequent development of recurrent and/or metastatic disease. Patients with sporadic PPGL were defined as those with negative genetic test results. RESULTS: Prevalence of recurrence among patients with sporadic PPGL (14.7%) was lower (P < 0.001) than for patients with pathogenic variants that activate pseudohypoxia pathways (47.5%), but similar to those with variants that activate kinase pathways (14.9%). Among patients with sporadic recurrent PPGL, 29.1% and 17.7% were respectively diagnosed at least 10 and 15 years after first diagnosis. Multivariable regression analysis showed that a noradrenergic/dopaminergic phenotype (HR 2.73; 95% CI, 1.553-4.802; P < 0.001), larger size (HR 1.82; 95% CI, 1.113-2.962; P = 0.017) and extra-adrenal location (HR 1.79; 95% CI, 1.002-3.187; P = 0.049) of primary tumors were independent predictors of recurrence in sporadic PPGL. CONCLUSION: Patients with sporadic PPGL require long-term follow-up, as supported by the 14.7% prevalence of recurrent disease, including recurrences at more than 10 years after first diagnosis. The nature of follow-up could be individualized according to tumor size, location, and biochemical phenotype.

Silent pheochromocytoma and paraganglioma: Systematic review and proposed definitions for standardized terminology.

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors with heterogeneous clinical presentations and potential lethal outcomes. The diagnosis is based on clinical suspicion, biochemical testing, imaging and histopathological confirmation. Increasingly widespread use of imaging studies and surveillance of patients at risk of PPGL due to a hereditary background or a previous tumor is leading to the diagnosis of these tumors at an early stage. This has resulted in an increasing use of the term "silent" PPGL. This term and other variants are now commonly found in the literature without any clear or unified definition. Among the various terms, "clinically silent" is often used to describe the lack of signs and symptoms associated with catecholamine excess. Confusion arises when these and other terms are used to define the tumors according to their ability to synthesize and/or release catecholamines in relation to biochemical test results. In such cases the term "silent" and other variants are often inappropriately and misleadingly used. In the present analysis we provide an overview of the literature and propose standardized terminology in an attempt at harmonization to facilitate scientific communication.

Cardiac Phenotypes in Secondary Hypertension: JACC State-of-the-Art Review.

Several forms of secondary hypertension carry a high risk of cardiac morbidity and mortality. Evaluation of cardiac phenotypes in secondary hypertension provides a unique opportunity to study underlying hormonal and biochemical mechanisms affecting the heart. We review the characteristics of cardiac dysfunction in different forms of secondary hypertension and clarify the mechanisms behind the higher prevalence of heart damage in these patients than in those with primary hypertension. Attention to the specific clinical/biochemical phenotypes of these conditions may assist clinicians to screen for and confirm secondary forms of hypertension. Thereby, early signs of heart damage can be recognized and monitored, allowing individualized treatment to delay or prevent evolution toward more advanced disease.

Integration of artificial intelligence and plasma steroidomics with laboratory information management systems: application to primary aldosteronism.

OBJECTIVES: Mass spectrometry-based steroidomics combined with machine learning (ML) provides a potentially powerful approach in endocrine diagnostics, but is hampered by limitations in the conveyance of results and interpretations to clinicians. We address this shortcoming by integration of the two technologies with a laboratory information management systems (LIMS) model. METHODS: The approach involves integration of ML algorithm-derived models with commercially available mathematical programming software and a web-based LIMS prototype. To illustrate clinical utility, the process was applied to plasma steroidomics data from 22 patients tested for primary aldosteronism (PA). RESULTS: Once mass spectrometry data are uploaded into the system, automated processes enable generation of interpretations of steroid profiles from ML models. Generated reports include plasma concentrations of steroids in relation to age- and sex-specific reference intervals along with results of ML models and narrative interpretations that cover probabilities of PA. If PA is predicted, reports include probabilities of unilateral disease and mutations of KCNJ5 known to be associated with successful outcomes of adrenalectomy. Preliminary results, with no overlap in probabilities of disease among four patients with and 18 without PA and correct classification of all four patients with unilateral PA including three of four with KCNJ5 mutations, illustrate potential utility of the approach to guide diagnosis and subtyping of patients with PA. CONCLUSIONS: The outlined process for integrating plasma steroidomics data and ML with LIMS may facilitate improved diagnostic-decision-making when based on higher-dimensional data otherwise difficult to interpret. The approach is relevant to other diagnostic applications involving ML.

Determinants of disease-specific survival in patients with and without metastatic pheochromocytoma and paraganglioma.

BACKGROUND: Pheochromocytomas and paragangliomas (PPGLs) have a heterogeneous prognosis, the basis of which remains unclear. We, therefore, assessed disease-specific survival (DSS) and potential predictors of progressive disease in patients with PPGLs and head/neck paragangliomas (HNPGLs) according to the presence or absence of metastases. METHODS: This retrospective study included 582 patients with PPGLs and 57 with HNPGLs. DSS was assessed according to age, location and size of tumours, recurrent/metastatic disease, genetics, plasma metanephrines and methoxytyramine. RESULTS: Among all patients with PPGLs, multivariable analysis indicated that apart from older age (HR = 5.4, CI = 2.93-10.29, P < 0.0001) and presence of metastases (HR = 4.8, CI = 2.41-9.94, P < 0.0001), shorter DSS was also associated with extra-adrenal tumour location (HR = 2.6, CI = 1.32-5.23, P = 0.0007) and higher plasma methoxytyramine (HR = 1.8, CI = 1.11-2.85, P = 0.0170) and normetanephrine (HR = 1.8, CI = 1.12-2.91, P = 0.0160). Among patients with HNPGLs, those with metastases presented with longer DSS compared to patients with metastatic PPGLs (33.4 versus 20.2 years, P < 0.0001) and only plasma methoxytyramine (HR = 13, CI = 1.35-148, P = 0.0380) was an independent predictor of DSS. For patients with metastatic PPGLs, multivariable analysis revealed that apart from older age (HR = 6.2, CI = 3.20-12.20, P < 0.0001), shorter DSS was associated with the presence of synchronous metastases (HR = 4.9, CI = 2.78-8.80, P < 0.0001), higher plasma methoxytyramine (HR = 2.4, CI = 1.44-4.14, P = 0.0010) and extensive metastatic burden (HR = 2.1, CI = 1.07-3.79, P = 0.0290). CONCLUSIONS: DSS among patients with PPGLs/HNPGLs relates to several presentations of the disease that may provide prognostic markers. In particular, the independent associations of higher methoxytyramine with shorter DSS in patients with HNPGLs and metastatic PPGLs suggest the utility of this biomarker to guide individualized management and follow-up strategies in affected patients.

The Saline Infusion Test for Primary Aldosteronism: Implications of Immunoassay Inaccuracy.

CONTEXT: Diagnosis of primary aldosteronism (PA) for many patients depends on positive results for the saline infusion test (SIT). Plasma aldosterone is often measured by immunoassays, which can return inaccurate results. OBJECTIVE: This study aimed to establish whether differences in aldosterone measurements by immunoassay versus mass spectrometry (MS) might impact confirmatory testing for PA. METHODS: This study, involving 240 patients tested using the SIT at 5 tertiary care centers, assessed discordance between immunoassay and MS-based measurements of plasma aldosterone. RESULTS: Plasma aldosterone measured by Liaison and iSYS immunoassays were respectively 86% and 58% higher than determined by MS. With an immunoassay-based SIT cutoff for aldosterone of 170 pmol/L, 78 and 162 patients had, respectivel, negative and positive results. All former patients had MS-based measurements of aldosterone < 117 pmol/L, below MS-based cutoffs of 162 pmol/L. Among the 162 patients with pathogenic SIT results, MS returned nonpathologic results in 62, including 32 under 117 pmol/L. Repeat measurements by an independent MS method confirmed nonpathogenic results in 53 patients with discordant results. Patients with discordant results showed a higher (P < 0.0001) prevalence of nonlateralized than lateralized adrenal aldosterone production than patients with concordant results (83% vs 28%). Among patients with nonlateralized aldosterone production, 66% had discordant results. Discordance was more prevalent for the Liaison than iSYS immunoassay (32% vs 16%; P = 0.0065) and was eliminated by plasma purification to remove interferents. CONCLUSION: These findings raise concerns about the validity of immunoassay-based diagnosis of PA in over 60% of patients with presumed bilateral disease. We provide a simple solution to minimize immunoassay inaccuracy-associated misdiagnosis of PA.

Differences in clinical presentation and management between pre- and postsurgical diagnoses of urinary bladder paraganglioma: is there clinical relevance? A systematic review.

PURPOSE: Paraganglioma of the urinary bladder (UBPGL) is a rare neuroendocrine tumor diagnosed in many patients only after surgery. We, therefore, assessed clinical clues relevant to presurgical diagnosis and clinical consequences in patients with a missed presurgical diagnosis of UBPGL. MATERIALS AND METHODS: Case reports describing a UBPGL (published from 1-1-2001 and 31-12-2020) were identified in Pubmed. Two authors independently performed data extraction and assessed data quality according to the PRISMA guideline. Patients were divided into two groups: UBPGL diagnosis before and after surgery. RESULTS: We included 177 articles reporting 194 cases. In 90 (46.4%) patients, the UBPGL was diagnosed before and in 104 (53.6%) after surgery. In presurgically diagnosed UBPGL, hypertension and catecholamine-associated symptoms were 2- to 3-fold (p < 0.001) more frequent than in postsurgically diagnosed patients whereas hematuria was twofold (p = 0.003) more prevalent in those with postsurgical diagnosis. Hypertension was an independent factor for presurgical biochemical testing (OR 4.45, 95% CI 1.66-11.94) while hematuria (OR 0.23, 95% CI 0.09-0.60) was an independent factor for not performing presurgical biochemical testing. Most patients diagnosed after surgery were not pretreated with alpha-adrenoceptor blockade (95.2%), underwent more frequently transurethral resection instead of cystectomy (70.2% vs. 23.1%) and had more frequent peroperative complications and residual tumor mass. CONCLUSIONS: In nearly half of all patients with a UBPGL, the diagnosis was not established before surgery. Hypertension and hematuria contributed independently to a presurgical diagnosis. Postsurgical diagnosis, which was associated with suboptimal presurgical and surgical management, resulted in more peroperative complications and incomplete tumor resections.