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28 result(s) for "Wildemberg, Luiz Eduardo"
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ODP354 Telomeres Length and Wnt/beta-catenin Pathway in Adamantinomatous Craniopharyngiomas
Objectives To evaluate how telomeres length behaves in adamantinomtous craniopharyngioma (aCP) and if it contributes to the pathogenesis of aCPs with and without CTNNB1 mutations. Design: Retrospective cross-sectional study enrolling 42 aCPpatients from two tertiary institutions. Methods Clinicopathological features were retrieved from patient's charts. Fresh frozen tumors were used for RNA and DNA analyses. Telomere length was evaluated by qPCR (T/S ratio). Somatic mutations in TERT promoter (TERTp) and CTNNB1 were detected by Sanger and/or whole-exome sequencing. We performed RNA-Seq to identify differentially expressed genes in aCPs presenting with shorter or longer telomere lengths. Results Mutations in CTNNB1 were detected in 29 (69%) tumors. There was higher frequency of CTNNB1mutations in aCPs from patients diagnosed under the age of 15 years (85% vs 15%; p=0. 04) and a trend to recurrent disease (76% vs 24%; p=0.1). No mutation was detected in the TERTp region. The telomeres were shorter in CTNNB1-mutated aCPs (0.441, IQR: 0.297-0.597 vs 0.607, IQR: 0.445-0.778; p=0. 04) but it was neither associated with clinicopathological features nor with recurrence. RNAseq identified a total of 387 differentially expressed genes, generating two clusters, being one enriched for short telomere and CTNNB1-mutated aCPs. Conclusions CTNNB1 mutations are more frequent in children and adolescents and appear to associate with progressive disease. CTNNB1-mutated aCPs have shorter telomeres. This is the first evidence for a relationship between the Wnt/beta-catenin pathway and telomere biology in the pathogenesis of aCPs. Presentation: No date and time listed
Low Aryl Hydrocarbon Receptor-Interacting Protein Expression Is a Better Marker of Invasiveness in Somatotropinomas than Ki-67 and p53
Background: Some pituitary adenomas exhibit fast growth and invade surrounding structures. To date, there is no robust marker to predict invasiveness. Aim: To evaluate Ki-67, p53 and aryl hydrocarbon receptor-interacting protein (AIP) expression and compare these between invasive and noninvasive somatotropinomas and nonfunctioning pituitary adenomas (NFPAs). Methods: Protein expression was determined by immunohistochemistry. Tumors were classified according to percentage of immunolabeled nuclei for Ki-67 and p53. AIP immunopositivity was graded according to a score encompassing pattern and intensity. Invasiveness was defined according to radiological and surgical criteria. Results: Thirty-eight sporadic somatotropinomas were studied. Median Ki-67 labeling index in invasive and noninvasive tumors was 1.6 (range 0–20.6) and 0.26 (0–2.2), respectively (p = 0.01). With a 2.3% cut-off point obtained by ROC curve analysis, invasive adenomas were distinguished with 100% specificity, 39% sensitivity, and 63% accuracy. Low AIP expression was also correlated with tumor invasiveness (p = 0.001), with sensitivity, specificity and accuracy of 78, 80, and 79%, respectively. Expression of p53 was not different among tumors. Twenty-nine NFPAs were studied, with no significant difference between Ki-67, p53 and AIP expression in invasive and noninvasive tumors. High AIP expression was more frequent in NFPAs, with Ki-67 >3% (p = 0.051), especially when only gonadotrope cell adenomas (n = 25) were considered (p = 0.012). Conclusions: These data suggest, for the first time, that AIP is a better marker of invasiveness in somatotropinomas than Ki-67 and p53. In addition, low AIP expression is observed in invasive somatotropinomas, in contrast with high AIP expression in NFPAs (mainly gonadotrope cell tumors) with high proliferative indices.
miR-383-5p, miR-181a-5p, and miR-181b-5p as Predictors of Response to First-Generation Somatostatin Receptor Ligands in Acromegaly
Acromegaly is a chronic systemic disease caused in the vast majority of cases by growth hormone (GH)-secreting adenoma, with surgery being the first-line treatment. When a cure is not attained with surgery, first-generation somatostatin receptor ligands (fg-SRLs) are the most common medication prescribed. Predictors of response to fg-SRLs have been studied; however, they cannot fully predict the response to fg-SRL. MicroRNAs are small RNAs, the main role of which is messenger RNA (mRNA) post-transcriptional regulation. This study aimed to identify the microRNAs involved in resistance to treatment with fg-SRLs in acromegaly. Ten patients with acromegaly undergoing treatment with fg-SRLs were selected to undergo miRNA sequencing: five controlled and five uncontrolled with treatment. Bioinformatic analysis was performed to detect differentially expressed miRNAs. Then, the same 10 samples were used for validation by qPCR and an additional 22 samples were analyzed, totaling 32 samples. e We found 59 differentially expressed miRNAs in the first analysis. miR-181a-5p and miR-181b-5p were downregulated, and miR-383-5p was upregulated in the uncontrolled group. Receiver operating characteristic (ROC) curve analysis of miR-383-5p showed an NPV of 84.3% and a PPV of 84.5%. In summary, miR-181a-5p, miR-181b-5p, and miR-383-5p are biomarkers of response to fg-SRLs, and they can be used individually or included in prediction models as tools to guide clinical decisions.
Sellar and suprasellar mixed germ cell tumor mimicking a pituitary adenoma
Germ cell tumors (GCT) are a heterogeneous group of lesions whose origin is not well established. Several cases of primary intrasellar germinomas have been reported, however non-germinomatous GCT have rarely been described. We report the case of a young adult male patient with a mixed GCT that presented with a sellar tumor with suprasellar extension. The patient seeked medical attention because of seizures and magnetic resonance imaging evidenced a tumor of the sellar region. Hyperprolactinemia was also present and dopamine agonist therapy was started. As there was a rapid tumor growth and the patient had concomitant central diabetes insipidus and elevated testosterone levels, a GCT was suspected and confirmed by elevated serum concentration of β-human chorionic gonadotrophin. Patient underwent surgical resection of the tumor and histopathological examination confirmed the diagnosis of a mixed GCT. Chemotherapy was initiated, followed by conventional radiotherapy. In conclusion, although pituitary adenomas respond for the vast majority of sellar tumors, concomitant symptoms such as central diabetes insipidus and rapid tumor growth should raise the suspicion of a diverse diagnosis. The present report intend not only to show a rare case of sellar and suprasellar mixed GCT but also to remind clinicians that if laboratory findings do not fit into patient’s diagnosis (such as high testosterone levels in our patient), then the diagnosis should be reviewed.
ZAC1 and SSTR2 Are Downregulated in Non-Functioning Pituitary Adenomas but Not in somatotropinomas
There are few data regarding ZAC1 expression in clinically non-functioning pituitary adenomas (NFPA). Because somatotropinomas and NFPA behave differently with respect to tumor shrinkage during somatostatin analogs (SA) therapy, we sought to compare the ZAC1 and somatostatin receptor (sstr) types 1, 2, 3 and 5 mRNA expression in these two pituitary adenoma subtypes and in normal human pituitaries. ZAC1 and SSTR mRNA expression levels were evaluated using real-time RT-PCR (TaqMan) in 20 NFPA and compared with the expression levels in 23 somatotropinomas and five normal pituitaries. The NFPA invasiveness was evaluated using magnetic resonance imaging with Hardy's modified criteria. Ki-67 and p53 were evaluated using immunohistochemistry. A total of 20 patients with NFPA [6 males, median age 56 years (range: 30-78)], 23 with acromegaly [12 males, median age 43 years (range: 24-57)] and five normal pituitaries [4 males, median age 48 years (range: 36-54)] were included. Four of the patients (20%) had Hardy's grade 2 tumors; all of the others had Hardy's grade 3 tumors. The Ki-67 median expression was 2.35 (range: 0.2-9.23), and only four of the tumors (20%) were positive for p53. The ZAC1 mRNA expression was significantly lower in NFPA than in somatotropinomas and in normal pituitaries (p<0.001 for both), as well as the SSTR2 (p=0.001 and 0.01, respectively). The SSTR3 expression was higher in the NFPA than in the somatotropinomas and in the normal pituitaries (p=0.03 and 0.02, respectively). No correlation was found between the ZAC1 mRNA expression and the tumor invasiveness, Ki-67 and p53. ZAC1 and SSTR2 are underexpressed and SSTR3 is overexpressed in NFPA compared to those in somatotropinomas and in normal pituitaries, which might explain the lack of tumor shrinkage that is observed in response to commercially available SA therapy in patients with NFPA.
Utility of ¹⁸F fluoro-2-deoxy-d-glucose positron emission tomography in the localization of ectopic ACTH-secreting tumors
Ectopically ACTH producing tumors may be difficult to localize by conventional radiology and functional imaging may be helpful. Case 1: 31-year-old man was diagnosed with ectopic ACTH-dependent Cushing's syndrome (ECS). Thorax CT revealed a 1.3 cm nodular opacity in upper left lobe, suggestive of residual lesion. [¹⁸F] fluoro-2-deoxy-d-glucose ([¹⁸F] FDG) positron emission tomography ([¹⁸F] FDG PET) scan revealed mild glycolytic metabolic activity. Pathological examination confirmed an ACTH-positive carcinoid tumor. Case 2: 53-year-old woman presented with very rapid onset ECS. Pituitary MRI was normal. Thorax CT revealed no tumoral lesion. Abdominal and pelvic MRI showed images suggestive of hepatic and iliac, femoral and lumbar secondary implants. [¹⁸F] FDG PET scan revealed intense uptake in uterus, especially cervix, suggesting this to be the primary tumor site. These cases illustrate the role of [¹⁸F] FDG PET in the investigation of an ECS where conventional imaging studies were not elucidative in the search for a responsible tumor.
Skeletal Muscle Evaluation in Patients With Acromegaly
Abstract Context Patients with acromegaly are characterized by chronic exposure to high growth hormone (GH) and insulin-like growth factor-1 levels, known for their anabolic effect on skeletal muscle. Therefore, an increased skeletal muscle mass could be hypothesized in these individuals. Herein, we have performed a systematic revision of published evidence regarding skeletal muscle mass, quality, and performance in patients with acromegaly. Evidence Acquisition A systematic review of the literature in the PubMed database up to September 1, 2023, was conducted with the following query: acromegaly AND (“muscle mass” OR “skeletal muscle”). We excluded studies that did not compare different disease states or used nonradiological methods for the skeletal muscle analyses, except for bioelectrical impedance analysis. Evidence Synthesis Fifteen studies met the inclusion criteria. A total of 360 patients were evaluated for skeletal muscle mass, 122 for muscle fatty atrophy, and 192 for muscle performance. No clear evidence of increased skeletal muscle mass in patients with active disease compared to control or healthy individuals emerged. As for skeletal muscle quality, we observed a trend toward higher fatty infiltration among patients with acromegaly compared to healthy participants. Likewise, patients with active disease showed consistently worse physical performance compared to control or healthy individuals. Conclusion Skeletal muscle in acromegaly has lower quality and performance compared to that of healthy individuals. The small number of published studies and multiple confounding factors (eg, use of different radiological techniques) contributed to mixed results, especially regarding skeletal muscle mass. Well-designed prospective studies are needed to investigate skeletal muscle mass in patients with acromegaly.
Cushing's syndrome
Endogenous Cushing's syndrome results from excess glucocorticoid secretion, which leads to a myriad of clinical manifestations, comorbidities, and increased mortality despite treatment. Molecular mechanisms and genetic alterations associated with different causes of Cushing's syndrome have been described in the last decade. Imaging modalities and biochemical testing have evolved; however, both the diagnosis and management of Cushing's syndrome remain challenging. Surgery is the preferred treatment for all causes, but medical therapy has markedly advanced, with new drug options becoming available. Nevertheless, several comorbidities remain even after patient remission, which can affect quality of life. Accurate and timely diagnosis and treatment are essential for mitigating chronic complications of excess glucocorticoids and improving patient quality of life. In this Seminar, we aim to update several important aspects of diagnosis, complications, and treatment of endogenous Cushing's syndrome of all causes.
Alternative Approach to BIPSS in the Differential Diagnosis of ACTH-Dependent Cushing Syndrome
Key Words: Cushing syndrome, Cushing disease, bilateral inferior petrosal sinus sampling, CRH, high dose dexamethasone suppression test, desmopressin
The Role of Temozolomide in the Treatment of a Patient With a Pure Silent Pituitary Somatotroph Carcinoma
To describe a case of a pure silent somatotroph pituitary carcinoma. We describe a 54-year-old female with a clinically nonfunctioning pituitary macroadenoma diagnosed 15 years earlier. The patient underwent transsphenoidal surgery and no visible tumor remnant was observed for 6 years. A magnetic resonance imaging (MRI) detected the recurrence of a 1.2 × 1.5 cm macroadenoma. The patient was submitted to conventional radiotherapy (4500 cGy), and the tumor volume remained stable for 7 years. Then, an MRI revealed a slight increase in tumor size, and 2 years later, a subsequent MRI detected a very large, invasive pituitary mass. The patient was resubmitted to transsphenoidal surgery, and the histopathological examination showed diffuse positivity for growth hormone (GH). The nadir GH level during an oral glucose tolerance test was 0.06 ng/mL, and the pre- and postoperative insulin like growth factor type I (IGF-I) levels were within the normal range. Abdominal, chest, brain, and spine MRI showed multiple small and hypervascular liver and bone lesions suggestive of metastases. Liver biopsy confirmed metastasis of GH-producing pituitary carcinoma. The patient has been treated with temozolomide and zoledronic acid for 7 months and with octreotide long-acting release (LAR) for 4 months. The primary tumor and metastases are stable. Despite being an extremely rare event, pituitary carcinoma may develop several years after the successful treatment of even a silent GH-producing pituitary adenoma, which suggests that close long-term follow-up is necessary.