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result(s) for
"Almeida, Madson Q"
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Perioperative Management of Pheochromocytomas and Sympathetic Paragangliomas
by
Fagundes, Gustavo F C
,
Almeida, Madson Q
in
Care and treatment
,
Dehydrogenases
,
Fludrocortisone
2022
Abstract
Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors arising from chromaffin cells of the adrenal medulla or extra-adrenal paraganglia, respectively. PPGLs have the highest degree of heritability among endocrine tumors. Currently, ~40% of individuals with PPGLs have a genetic germline and there are at least 12 different genetic syndromes related to these tumors. Metastatic PPGLs are defined by the presence of distant metastases at sites where chromaffin cells are physiologically absent. Approximately 10% of pheochromocytomas and ~40% of sympathetic paragangliomas are linked to metastases, explaining why complete surgical resection is the first-choice treatment for all PPGL patients. The surgical approach is a high-risk procedure requiring perioperative management by a specialized multidisciplinary team in centers with broad expertise. In this review, we summarize and discuss the most relevant aspects of perioperative management in patients with pheochromocytomas and sympathetic paragangliomas.
Journal Article
Clinical Impact of Pathological Features Including the Ki-67 Labeling Index on Diagnosis and Prognosis of Adult and Pediatric Adrenocortical Tumors
by
Fragoso Maria Candida Barisson V
,
Zerbini Maria Claudia N
,
Wakamatsu Alda
in
Adrenocorticotropic hormone
,
Adults
,
Carcinoma
2021
Adrenocortical tumors (ACT) in the adult and pediatric population are generally considered distinct entities due to differences in molecular events related to tumorigenesis, clinical presentation, and outcome. Furthermore, pathological criteria used for diagnosis and prognostication of ACT in adults are usually inadequate for predicting the biological behavior of ACT in children. Here, we analyzed 146 adult and 44 pediatric (< 15y/o) ACT with long-term clinical follow-up and furthered current evidence on the clinical and pathological differences between pediatric and adult tumors. Predilection for female over male gender was observed in both cohorts, but more so in adults (84% vs. 61%, p = 0.003). Cushing syndrome was more frequent in adults (p < 0.001), whereas virilization, either isolated (p < 0.001) or combined to Cushing (p = 0.047), was more common in children. The Ki67 labelling index (LI) of pediatric adenomas and carcinomas was much higher than their corresponding tumors in adults (p < 0.001). Despite these differences, pathological analyses including the evaluation of Ki67 greatly improved patient prognostication in both age cohorts. Indeed, increased Weiss scores and Ki67 indexes correlated with poor overall- and disease-free survival in adult patients with carcinoma. Among the proliferative indexes tested, Ki67 LI ≥ 10% showed the highest hazard ratio (HR) for recurrence and the Ki67 LI ≥ 3% showed the highest HR for survival. In pediatric tumors, the Wieneke score (p < 0.001) and the Ki67 LI (p < 0.001) showed high accuracy for predicting biological behavior, and increased scores/indexes correlated with worse overall and disease-free survival. In this age cohort, Ki67 LI < 10% was able to rule out malignant behavior, whereas Ki67 LI ≥ 15% may be used to predict the patients with higher risks of recurrence and/or poor outcome.
Journal Article
Sterol O-Acyl Transferase 1 as a Prognostic Marker of Adrenocortical Carcinoma
by
Brondani, Vania Balderrama
,
Chambo, José Luiz
,
Zerbini, Maria Claudia Nogueira
in
Biomarkers
,
Cancer
,
Cell viability
2020
Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with an unfavorable prognosis. Despite the poor prognosis in the majority of patients, no improvements in treatment strategies have been achieved. Therefore, the discovery of new prognostic biomarkers is of enormous interest. Sterol-O-acyl transferase 1 (SOAT1) is involved in cholesterol esterification and lipid droplet formation. Recently, it was demonstrated that SOAT1 inhibition leads to impaired steroidogenesis and cell viability in ACC. To date, no studies have addressed the impact of SOAT1 expression on ACC prognosis and clinical outcomes. We evaluated SOAT1 expression by quantitative real-time polymerase chain reaction and immunohistochemistry in a tissue microarray of 112 ACCs (Weiss score ≥ 3) from adults treated in a single tertiary center in Brazil. Two independent pathologists evaluated the immunohistochemistry results through a semiquantitative approach (0–4). We aimed to evaluate the correlation between SOAT1 expression and clinical, biochemical and anatomopathological parameters, recurrence-free survival (RFS), progression-free survival (PFS), and overall survival (OS). SOAT1 protein expression was heterogeneous in this cohort, 37.5% of the ACCs demonstrated a strong SOAT1 protein expression (score > 2), while 62.5% demonstrated a weak or absent protein expression (score ≤ 2). Strong SOAT1 protein expression correlated with features of high aggressiveness in ACC, such as excessive tumor cortisol secretion (p = 0.01), an advanced disease stage [European Network for the Study of Adrenal Tumors (ENSAT) staging system 3 and 4 (p = 0.011)] and a high Ki67 index (p = 0.002). In multivariate analysis, strong SOAT1 protein expression was an independent predictor of a reduced OS (hazard ratio (HR) 2.15, confidence interval (CI) 95% 1.26–3.66; p = 0.005) in all patients (n = 112), and a reduced RFS (HR 2.1, CI 95% 1.09–4.06; p = 0.027) in patients with localized disease at diagnosis (n = 83). Our findings demonstrated that SOAT1 protein expression has prognostic value in ACC and reinforced the importance of investigating SOAT1 as a possible therapeutic target for patients with ACC.
Journal Article
Cutoff Values of Aldosterone and the Aldosterone–Renin Ratio for Predicting Primary Aldosteronism in Patients with Resistant Hypertension: A Real-Life Study
by
Bortolotto, Luiz Aparecido
,
Drager, Luciano F.
,
Macedo, Thiago
in
Aldosterone
,
aldosterone–renin ratio
,
Antihypertensive drugs
2024
Primary aldosteronism (PA) is commonly associated with resistant hypertension. Biochemical tests can be clinically useful in the screening and diagnosis of primary aldosteronism. This study aimed to identify the cutoff values of aldosterone levels (A) and the aldosterone–renin ratio (ARR) for an accurate prediction of PA in patients with apparent resistant hypertension in a real-life scenario. This database-based study included a historical cohort of male and female patients with apparent resistant hypertension, aged 18 years or older and surveyed for PA in a specialized center from 2008 to 2018. Aldosterone and plasma renin activity (PRA) or the plasma renin concentration (PRC) were measured in the treated hypertensive patients. The patients with positive screening results were subsequently referred to the endocrinology department for confirmatory tests. The patients with confirmed PA were included in the case group, and the others remained as controls. Receiver-operating characteristic (ROC) curves were used to identify the cutoff points for aldosterone and the ARR, thereby analyzing their sensitivity and specificity for confirmed PA. Among the 3464 patients (59 ± 13 years old, 41% male) who had apparent resistance hypertension screened, PA was confirmed in 276 individuals (8%). A ≥ 16.95 ng/dL (95% CI: 0.908–0.933) had an odds ratio of 6.24 for PA, while A/PRA ≥ 29.88 (95% CI: 0.942–0.984) or an A/PRC ≥ 2.44 (95% CI: 0.978–0.990) had an odds ratio of 216.17 for PA diagnoses. Our findings suggest that a positive PA screening with aldosterone ≥ 17 ng/dL associated with A/PRA ≥ 29.88 or an A/PRC ratio of ≥2.44 should be sufficient to confirm the diagnosis of PA without confirmatory testing.
Journal Article
Alternate protein kinase A activity identifies a unique population of stromal cells in adult bone
by
Mertz, Edward L
,
Leikin, Sergey
,
Starost, Matthew F
in
adults
,
Aging - pathology
,
animal models
2010
A population of stromal cells that retains osteogenic capacity in adult bone (adult bone stromal cells or aBSCs) exists and is under intense investigation. Mice heterozygous for a null allele of prkar1a (Prkar1a⁺/⁻), the primary receptor for cyclic adenosine monophosphate (cAMP) and regulator of protein kinase A (PKA) activity, developed bone lesions that were derived from cAMP-responsive osteogenic cells and resembled fibrous dysplasia (FD). Prkar1a⁺/⁻ mice were crossed with mice that were heterozygous for catalytic subunit Cα (Prkaca⁺/⁻), the main PKA activity-mediating molecule, to generate a mouse model with double heterozygosity for prkar1a and prkaca (Prkar1a⁺/⁻Prkaca⁺/⁻). Unexpectedly, Prkar1a⁺/⁻Prkaca⁺/⁻ mice developed a greater number of osseous lesions starting at 3 months of age that varied from the rare chondromas in the long bones and the ubiquitous osteochondrodysplasia of vertebral bodies to the occasional sarcoma in older animals. Cells from these lesions originated from an area proximal to the growth plate, expressed osteogenic cell markers, and showed higher PKA activity that was mostly type II (PKA-II) mediated by an alternate pattern of catalytic subunit expression. Gene expression profiling confirmed a preosteoblastic nature for these cells but also showed a signature that was indicative of mesenchymal-to-epithelial transition and increased Wnt signaling. These studies show that a specific subpopulation of aBSCs can be stimulated in adult bone by alternate PKA and catalytic subunit activity; abnormal proliferation of these cells leads to skeletal lesions that have similarities to human FD and bone tumors.
Journal Article
What Is the Most Common Cause of Secondary Hypertension?: An Interdisciplinary Discussion
by
Drager, Luciano F
,
Almeida, Madson Q
,
Silva, Giovanio V
in
Endocrine disorders
,
Gastrointestinal surgery
,
Hypertension
2020
Purpose of ReviewTraditional statements in medical textbooks pointed that 90 to 95% of cases of hypertension is essential or primary. However, secondary hypertension seems to be common in those patients with resistant forms of hypertension. Appropriate investigation and treatment may have prognostic impact but frequently hypertension remission did not occur raising concerns about the real meaning of secondary hypertension. Here, we provided an interdisciplinary and critical discussion comprising an endocrinologist, a nephrologist, and a cardiologist with expertise in resistant hypertension. We reviewed the literature approaching each one of the recognizable cause of hypertension.Recent FindingsRecent studies pointed that the most common causes of secondary hypertension are those who overall responses to their treatments do not promote hypertension remission including obstructive sleep apnea (OSA), chronic kidney disease, renovascular hypertension and primary aldosteronism. The authors raised concerns regarding the lack of inclusion of obesity by several societies as a formal cause of hypertension considering not only the biologic plausibility but also the huge impact of weight loss therapies such as bariatric surgery on hypertension remission. In contrast, there is no discussion that a very rare condition—namely pheochromocytoma—is the most “typical” cause of hypertension by promoting hypertension remission in the majority of patients after surgical procedure.SummaryHypertension is a complex condition with multiple environmental and genetics interactions. In clinical practice, it is challenging to prove causality in hypertension. Common conditions largely acceptable as causes of hypertension (OSA, chronic kidney disease, renovascular hypertension, and primary aldosteronism) frequently occur in a setting of an established hypertension background and therefore do not promote hypertension remission in a significant proportion of patients. If obesity becomes largely accepted by several societies as a secondary form of hypertension, this pandemic condition will be certainly the most common cause of hypertension.
Journal Article
Pitfalls in the Diagnostic Evaluation of Pheochromocytomas
2024
Abstract
Pheochromocytomas and paragangliomas (PPGLs), rare neuroendocrine tumors arising from chromaffin cells, present a significant diagnostic challenge due to their clinical rarity and polymorphic symptomatology. The clinical cases demonstrate the importance of an integrated approach that combines clinical assessment, biochemical testing, and imaging to distinguish PPGLs from mimicking conditions, such as obstructive sleep apnea and interfering medication effects, which can lead to false-positive biochemical results. Although a rare condition, false-negative metanephrine levels can occur in pheochromocytomas, but imaging findings can give some clues and increase suspicion for a pheochromocytoma diagnosis. This expert endocrine consult underscores the critical role of evaluating preanalytical conditions and pretest probability in the biochemical diagnosis of PPGLs. Moreover, a careful differentiation of PPGLs from similar conditions and careful selection and interpretation of diagnostic tests, with focus on understanding and reducing false positives to enhance diagnostic accuracy and patient outcomes, is crucial.
Journal Article
Intra-individual Variability of Serum Aldosterone and Implications for Primary Aldosteronism Screening
by
Mendonca, Berenice B
,
Silveira, João V
,
Zerbini, Maria Claudia N
in
Aldosterone
,
Antihypertensive drugs
,
Antihypertensives
2023
Abstract
Context
Primary aldosteronism (PA) screening relies on an elevated aldosterone to renin ratio with a minimum aldosterone level, which varies from 10 to 15 ng/dL (277-415.5 pmol/L) using immunoassay.
Objective
To evaluate intra-individual coefficient of variation (CV) of aldosterone and aldosterone to direct renin concentration ratio (A/DRC) and its impact on PA screening.
Methods
A total of 671 aldosterone and DRC measurements were performed by the same chemiluminescence assays in a large cohort of 216 patients with confirmed PA and at least 2 screenings.
Results
The median intra-individual CV of aldosterone and A/DRC was 26.8% and 26.7%. Almost 40% of the patients had at least one aldosterone level <15 ng/dL, 19.9% had at least 2 aldosterone levels <15 ng/dL, and 16.2% had mean aldosterone levels <15 ng/dL. A lower cutoff of 10 ng/dL was associated with false negative rates for PA screening of 14.3% for a single aldosterone measurement, 4.6% for 2 aldosterone measurements, and only 2.3% for mean aldosterone levels. Considering the minimum aldosterone, true positive rate of aldosterone thresholds was 85.7% for 10 ng/dL and 61.6% for 15 ng/dL. An A/DRC >2 ng/dL/µIU/mL had a true positive rate for PA diagnosis of 94.4% and 98.4% when based on 1 or 2 assessments, respectively. CV of aldosterone and A/DRC were not affected by sex, use of interfering antihypertensive medications, PA lateralization, hypokalemia, age, and number of hormone measurements.
Conclusion
Aldosterone concentrations had a high CV in PA patients, which results in an elevated rate of false negatives in a single screening for PA. Therefore, PA screening should be based on at least 2 screenings with concomitant aldosterone and renin measurements.
Journal Article