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354 result(s) for "Thyroid Nodule - genetics"
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Molecular Profiling of 50 734 Bethesda III-VI Thyroid Nodules by ThyroSeq v3: Implications for Personalized Management
Abstract Context Comprehensive genomic analysis of thyroid nodules for multiple classes of molecular alterations detected in a large series of fine needle aspiration (FNA) samples has not been reported. Objective To determine the prevalence of clinically relevant molecular alterations in Bethesda categories III-VI (BCIII-VI) thyroid nodules. Methods This retrospective analysis of FNA samples, tested by ThyroSeq v3 using Genomic Classifier and Cancer Risk Classifier at UPMC Molecular and Genomic Pathology laboratory, analyzed the prevalence of diagnostic, prognostic, and targetable genetic alterations in a total of 50 734 BCIII-VI nodules from 48 225 patients. Results Among 50 734 informative FNA samples, 65.3% were test-negative, 33.9% positive, 0.2% positive for medullary carcinoma, and 0.6% positive for parathyroid. The benign call rate in BCIII-IV nodules was 68%. Among test-positive samples, 73.3% had mutations, 11.3% gene fusions, and 10.8% isolated copy number alterations. Comparing BCIII-IV nodules with BCV-VI nodules revealed a shift from predominantly RAS-like alterations to BRAF V600E-like alterations and fusions involving receptor tyrosine kinases (RTK). Using ThyroSeq Cancer Risk Classifier, a high-risk profile, which typically included TERT or TP53 mutations, was found in 6% of samples, more frequently BCV-VI. RNA-Seq confirmed ThyroSeq detection of novel RTK fusions in 98.9% of cases. Conclusion In this series, 68% of BCIII-IV nodules were classified as negative by ThyroSeq, potentially preventing diagnostic surgery in this subset of patients. Specific genetic alterations were detected in most BCV-VI nodules, with a higher prevalence of BRAF and TERT mutations and targetable gene fusions compared to BCIII-IV nodules, offering prognostic and therapeutic information for patient management.
Preoperative Diagnosis of Benign Thyroid Nodules with Indeterminate Cytology
A significant fraction of fine-needle aspirates obtained from thyroid nodules are read as indeterminate. A new molecular test accurately predicts whether a cytologically indeterminate nodule is benign 93% of the time, permitting a conservative approach to management. Thyroid nodules are common and are usually benign. 1 However, 5 to 15% prove to be malignant; accordingly, identification of a nodule 1 cm or larger in diameter often prompts a diagnostic evaluation. 2 , 3 The cornerstone of thyroid-nodule evaluation is fine-needle aspiration, 4 which enables the assessment of cellular morphologic features that could not be identified by means of clinical assessment or imaging. Preoperative, ultrasonographically guided fine-needle aspiration has been shown to accurately classify 62 to 85% of thyroid nodules as benign, thereby avoiding diagnostic surgery. 5 However, 15 to 30% of aspirations yield indeterminate cytologic findings, 4 which include three subtypes: “atypia (or . . .
Real-World Performance of the Afirma Genomic Sequencing Classifier (GSC)—A Meta-analysis
Abstract Context The Afirma® GSC aids in risk stratifying indeterminate thyroid nodule cytology (ITN). The 2018 GSC validation study (VS) reported a sensitivity (SN) of 91%, specificity (SP) of 68%, positive predictive value (PPV) of 47%, and negative predictive value (NPV) of 96%. Since then, 13 independent real-world (RW) postvalidation studies have been published. Objective This study's objective is to compare the RW GSC performance to the VS metrics. Methods Rules and assumptions applying to this analysis include: (1) At least 1 patient with molecular benign results must have surgery for that study to be included in SN, SP, and NPV analyses. (2) Molecular benign results without surgical histology are considered true negatives (TN) (as are molecular benign results with benign surgical histology). (3) Unoperated patients with suspicious results are either excluded from analysis (observed PPV [oPPV] and observed SP [oSP]) or assumed histology negatives (false positives; conservative PPV [cPPV] and conservative SP [cSP]) 4. Noninvasive follicular thyroid neoplasm with papillary-like nuclear features is considered malignant. Results In RW studies, the GSC demonstrates a SN, oSP, oPPV, and NPV of 97%, 88%, 65%, 99% respectively, and conservative RW performance showed cSP of 80% and cPPV of 49%, all significantly higher than the VS except for SN and cPPV. There was also a higher benign call rate (BCR) of 67% in RW studies compared to 54% in the VS (P < 0.05). Conclusion RW data for the Afirma GSC demonstrates significantly better oSP and oPPV performance than the VS, indicating an increased yield of cancers for resected GSC suspicious nodules. The higher BCR likely increases the overall rate of clinical observation in lieu of surgery.
Afirma Genomic Sequencing Classifier and Xpression Atlas Molecular Findings in Consecutive Bethesda III-VI Thyroid Nodules
Abstract Context Broad genomic analyses among thyroid histologies have been described from relatively small cohorts. Objective Investigate the molecular findings across a large, real-world cohort of thyroid fine-needle aspiration (FNA) samples. Design Retrospective analysis of RNA sequencing data files. Setting Clinical Laboratory Improvement Amendments laboratory performing Afirma Genomic Sequencing Classifier (GSC) and Xpression Atlas (XA) testing. Participants A total of 50 644 consecutive Bethesda III-VI nodules. Intervention None. Main Outcome Measures Molecular test results. Results Of 48 952 Bethesda III/IV FNAs studied, 66% were benign by Afirma GSC. The prevalence of BRAF V600E was 2% among all Bethesda III/IV FNAs and 76% among Bethesda VI FNAs. Fusions involving NTRK, RET, BRAF, and ALK were most prevalent in Bethesda V (10%), and 130 different gene partners were identified. Among small consecutive Bethesda III/IV sample cohorts with one of these fusions and available surgical pathology excision data, the positive predictive value of an NTRK or RET fusion for carcinoma or noninvasive follicular thyroid neoplasm with papillary-like nuclear features was >95%, whereas for BRAF and ALK fusions it was 81% and 67%, respectively. At least 1 genomic alteration was identified by the expanded Afirma XA panel in 70% of medullary thyroid carcinoma classifier–positive FNAs, 44% of Bethesda III or IV Afirma GSC suspicious FNAs, 64% of Bethesda V FNAs, and 87% of Bethesda VI FNAs. Conclusions This large study demonstrates that almost one-half of Bethesda III/IV Afirma GSC suspicious and most Bethesda V/VI nodules had at least 1 genomic variant or fusion identified, which may optimize personalized treatment decisions.
Outcomes of Cytologically Indeterminate Thyroid Nodules Managed With Genomic Sequencing Classifier
Abstract Context Molecular testing can refine the risk of malignancy in thyroid nodules with indeterminate cytology to decrease unnecessary diagnostic surgery. Objective This study was performed to evaluate the outcomes of cytologically indeterminate thyroid nodules managed with Afirma genomic sequencing classifier (GSC) testing. Methods Adult patients who underwent a biopsy at 3 major academic centers between July 2017 and June 2021 with Bethesda III or IV cytology were included. All patients had surgery or minimum follow-up of 1 year ultrasound surveillance. The primary outcomes were the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of GSC in Bethesda III and IV nodules. Results The median nodule size of the 834 indeterminate nodules was 2.1 cm and the median follow-up was 23 months. GSC sensitivity, specificity, PPV, and NPV across all institutions were 95%, 81%, 50%, and 99% for Bethesda III nodules and 94%, 82%, 65%, and 98% for Bethesda IV nodules, respectively. The overall false-negative rate was 2%. The NPV of GSC in thyroid nodules with oncocytic predominance was 100% in Bethesda III nodules and 98% in Bethesda IV nodules. However, the PPV of oncocytic nodules was low (17% in Bethesda III nodules and 45% in Bethesda IV nodules). Only 22% of thyroid nodules with benign GSC results grew during surveillance. Conclusion GSC is a key tool for managing patients with indeterminate cytology, including the higher-risk Bethesda IV category. GSC-benign thyroid nodules can be observed similarly to thyroid nodules with benign cytology.
MeIS: DNA Methylation-Based Immune Response Signatures for Thyroid Nodule Diagnostics
Abstract Context Accurately distinguishing between benign thyroid nodules (BTNs) and papillary thyroid cancers (PTCs) with current conventional methods poses a significant challenge. Objective We identify DNA methylation markers of immune response–related genes for distinguishing BTNs and PTCs. Methods In this study, we analyzed a public reduced representative bisulfite sequencing dataset and revealed distinct methylation patterns associated with immune signals in PTCs and BTNs. Based on these findings, we developed a diagnostic classifier named the Methylation-based Immune Response Signature (MeIS), which was composed of 15 DNA methylation markers associated with immune response–related genes. We validated MeIS's performance in 2 independent cohorts: Z.S.'s retrospective cohort (50 PTC and 18 BTN surgery-leftover samples) and Z.S.'s preoperative cohort (31 PTC and 30 BTN fine-needle aspiration samples). Results The MeIS classifier demonstrated significant clinical promise, achieving areas under the curve of 0.96, 0.98, 0.89, and 0.90 in the training set, validation set, Z.S.'s retrospective cohort, and Z.S.'s preoperative cohort, respectively. For the cytologically indeterminate thyroid nodules, in Z.S.'s retrospective cohort, MeIS exhibited a sensitivity of 91% and a specificity of 82%; in Z.S.'s preoperative cohort, MeIS achieved a sensitivity of 84% and a specificity of 74%. Additionally, combining MeIS and BRAF V600E detection improved the detecting performance of cytologically indeterminate thyroid nodules, yielding sensitivities of 98% and 87%, and specificities of 82% and 74% in Z.S.'s retrospective cohort and Z.S.'s preoperative cohort, respectively. Conclusion The 15 markers we identified can be employed to improve the diagnostic of cytologically indeterminate thyroid nodules.
Thyroid Nodules: Advances in Evaluation and Management
Thyroid nodules can be detected by ultrasonography in up to 68% of the general population. They are typically benign and are often discovered incidentally. The primary goal of thyroid nodule evaluation is to determine whether it is malignant. After thyroid ultrasonography has been performed, the next step is measurement of serum thyroid-stimulating hormone. If levels are low, a radionuclide thyroid uptake scan is indicated. Hyperfunctioning nodules are rarely malignant and do not require tissue sampling. Nonfunctioning nodules and nodules in a patient with a normal or high thyroid-stimulating hormone level may require fine-needle aspiration based on ultrasound characteristics and size. Nodules with suspicious features and solid hypoechoic nodules 1 cm or larger require aspiration. The Bethesda System (categories 1 through 6) is used to classify samples. Molecular testing can be used to guide treatment when aspiration yields an indeterminate result. Molecular testing detects mutations associated with thyroid cancer and can help inform decisions about surgical excision vs. continued ultrasound monitoring. Treatment of pregnant women with nonfunctioning thyroid nodules and of children with thyroid nodules is similar to that for nonpregnant adults, with the exception of molecular testing, which has not been validated in these populations.
Role of Molecular Markers in Thyroid Nodule Management: Then and Now
To describe the evolution and clinical utility of molecular testing for thyroid nodules and cancer achieved over the last 2 decades. Scientific reports on thyroid cancer genetics and molecular diagnostics in thyroid nodules. Over the last 2 decades, our understanding of the genetic mechanisms of thyroid cancer has dramatically expanded, such that most thyroid cancers now have known gene driver events. This knowledge provides the basis for establishing and further improving molecular tests for thyroid nodules and cancer and for the introduction of new entities such as noninvasive follicular thyroid neoplasm with papillary-like nuclear features. The progress with molecular tests for thyroid nodules started in the 1990s from demonstrating feasibility of detecting various molecular alterations in fine-needle aspiration (FNA) material collected from thyroid nodules. It was followed by the introduction of the first single-gene mutational markers, such as BRAF, and a small mutational panel into clinical practice in the mid 2000s. Currently, several more advanced molecular tests are available for clinical use. They are based on multiple molecular markers and have increasing impact on the clinical management of patients with thyroid nodules. The evolution of molecular tests for thyroid nodules followed the discovery of various diagnostic and prognostic molecular markers of thyroid cancer that can be applied to thyroid FNA samples to inform more individualized management of these patients. FNA = fine-needle aspiration miRNA = micro RNA NGS = next-generation sequencing NIFTP = noninvasive follicular thyroid neoplasm with papillary-like nuclear features NPV = negative predictive value PPV = positive predictive value PTC = papillary thyroid carcinoma RAI = radioactive iodine.
DICER1 Mutations Are Frequent in Adolescent-Onset Papillary Thyroid Carcinoma
Abstract Context Papillary thyroid carcinoma (PTC) is a common malignancy in adolescence and is molecularly and clinically distinct from adult PTC. Mutations in the DICER1 gene are associated with thyroid abnormalities, including multinodular goiter and differentiated thyroid carcinoma. Objective In this study, we sought to characterize the prevalence of DICER1 variants in pediatric PTC, specifically in tumors without conventional PTC oncogenic alterations. Patients Patients (N = 40) who underwent partial or total thyroidectomy and who were <18 years of age at the time of surgery were selected. Design The 40 consecutive thyroidectomy specimens (30 malignant, 10 benign) underwent genotyping for 17 PTC-associated variants, as well as full sequencing of the exons and exon-intron boundaries of DICER1. Results Conventional alterations were found in 12 of 30 (40%) PTCs (five BRAFV600E, three RET/PTC1, four RET/PTC3). Pathogenic DICER1 variants were identified in 3 of 30 (10%) PTCs and in 2 of 10 (20%) benign nodules, all of which lacked conventional alterations and did not recur during follow-up. DICER1 alterations thus constituted 3 of 18 (16.7%) PTCs without conventional alterations. The three DICER1-mutated carcinomas each had two somatic DICER1 alterations, whereas two follicular-nodular lesions arose in those with germline DICER1 mutations and harbored characteristic second somatic RNase IIIb “hotspot” mutations. Conclusions DICER1 is a driver of pediatric thyroid nodules, and DICER1-mutated PTC may represent a distinct class of low-risk malignancies. Given the prevalence of variants in children, we advocate for inclusion of DICER1 sequencing and gene dosage determination in molecular analysis of pediatric thyroid specimens. In this study, the authors establish DICER1 as a common driver in ATA low-risk pediatric PTC. Of the tumors lacking conventional oncogenic alterations, 16.7% carried pathogenic DICER1 variants.
Prevalence and diagnostic reliability of BRAF, RAS mutations, and RET/PTC rearrangements in a Latin American public health service population with thyroid nodular disease
Despite their high prevalence and generally benign nature in most cases, the investigation of thyroid nodules still presents potential diagnostic pitfalls, especially in cases with indeterminate cytology results. The performance of molecular markers of thyroid cancer may vary across centers and populations. This study aimed to verify the prevalence of mutations in the BRAF, and RAS genes, and RET/PTC rearrangements in patients undergoing fine-needle aspiration biopsy (FNAB) for thyroid nodule evaluation in a real-world public health service population. Point mutations and rearrangements were detected by Sanger DNA sequencing. A total of 231 thyroid nodules in 220 patients were evaluated, being 86.8% females and a mean age of 55.6 ± 13.9 years. For molecular analysis, high-quality DNA and RNA were obtained from 200 samples. Mutations or rearrangements in target genes were identified in 14% of the 200 samples evaluated. The frequency of the BRAF -like mutations was 5.5%, detected in 9 out of 17 malignant nodules (52.9%) and one in a benign nodule (0.7%). Fourteen RAS- like mutations were identified in benign nodules (57.1% HRAS , 21.5% NRAS and 21.5% KRAS ) and only one was present in a malignant nodule (5.9%). Considering only nodules with indeterminate cytology (Bethesda III and IV, n = 53), 9 mutations were detected, 6 in benign histology (all RAS -like), 1 in malignant histology ( BRAF- like), and 2 still unoperated, therefore without a histopathological diagnosis. This research concludes that the presence of the BRAF V600E mutation could be useful in supporting the diagnosis of thyroid cancer, due to its high positive predictive value, since 89% of nodules with BRAF V600E mutation were malignant. Additionally, clinical criteria should be established to determine which nodules with RAS -like mutations require closer follow-up, particularly those with indeterminate cytology.