TERT Immunohistochemistry Expression as a Surrogate of TERT Promoter Mutations in Infiltrating Gliomas

2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S142-S142
Author(s):  
A M Moosvi ◽  
A Dono ◽  
A Bellman ◽  
L Ballester ◽  
P Goli ◽  
...  

Abstract Introduction/Objective Genomic alterations are critical for the diagnosis of infiltrating gliomas. Mutations in the telomerase reverse transcriptase promoter (TERTp) are sufficient for a diagnosis of glioblastoma in some cases, independent of histologic features. Although DNA sequencing is the preferred method for evaluating TERTp mutations, there are limitations with regards to turn-around-time, accessibility, and cost. In this study, we evaluated the efficacy of using TERT immunohistochemistry (IHC) as a surrogate marker for the identification of TERTp mutations in infiltrating gliomas. Methods/Case Report The study cohort consisted of 31 infiltrating gliomas diagnosed following the 2016 WHO classification of CNS tumors by a board-certified neuropathologist. Each case was evaluated by immunohistochemistry (anti-TERT monoclonal antibody) and with a targeted next-generation sequencing (NGS) panel. A systemic literature search was conducted to examine reports of TERT antibody as a surrogate marker of TERTp mutations. TERTp mutation detected by sequencing was considered the gold standard. Results (if a Case Study enter NA) TERT immunohistochemistry demonstrated a sensitivity of 61.1% and specificity of 69.2%. Cases were divided into IDH-WT and IDH-mutant infiltrating gliomas. Among the IDH-WT group, 84% contained the TERTp mutation with a sensitivity of 62.5% and specificity of 33.3% for the TERTp IHC. IDH-mutant gliomas showed a 16.2% TERTp mutation rate, and immunohistochemistry had a sensitivity of 50% and 80% specificity. The probability of TERT immunohistochemistry in diagnosing TERTp mutations exhibited a poor likelihood ratio for both the positive and negative test. Literature review included 5 studies with an overall sensitivity and specificity remaining consistently low (<80%), with 2 of these studies evaluating CNS related tumors giving rise to similar diagnostic performance. Conclusion TERT IHC has suboptimal sensitivity and specificity for identifying TERTp mutations in IDH-WT and IDH- mutant infiltrating gliomas.

Dermato ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 18-25
Author(s):  
Philipp Jansen ◽  
Georg Christian Lodde ◽  
Anne Zaremba ◽  
Carl Maximilian Thielmann ◽  
Johanna Matull ◽  
...  

Mutations in the promoter of the telomerase reverse transcriptase (TERT) gene have been described as the most common hot-spot mutations in different solid tumors. High frequencies of TERT promoter mutations have been reported to occur in tumors arising in tissues with low rates of self-renewal. For cutaneous vascular tumors, the prevalence of TERT promoter mutations has not yet been investigated in larger mixed cohorts. With targeted next-generation sequencing (NGS), we screened for different known recurrent TERT promoter mutations in various cutaneous vascular proliferations. In our cohort of 104 representative cutaneous vascular proliferations, we identified 7 TERT promoter mutations. We could show that 4 of 64 (6.3%) hemangiomas and vascular malformations harbored TERT promoter mutations (1 Chr.5:1295228 C > T mutations, 1 Chr.5:1295228_9 CC > TT mutation, and 2 Chr.5:1295250 C > T mutations), 1 of 19 (5.3%) angiosarcomas harbored a Chr.5:1295250 C > T TERT promoter mutation, and 2 of 21 (9.5%) Kaposi’s sarcomas harbored TERT promoter mutations (2 Chr.5:1295250 C > T mutations). To our knowledge, this is the first general description of the distribution of TERT promoter mutations in a mixed cohort of cutaneous vascular tumors, revealing that TERT promoter mutations seem to occur with low prevalence in both benign and malignant cutaneous vascular proliferations.


2017 ◽  
Vol 2 ◽  
pp. 35 ◽  
Author(s):  
Shazia Mahamdallie ◽  
Elise Ruark ◽  
Shawn Yost ◽  
Emma Ramsay ◽  
Imran Uddin ◽  
...  

Detection of deletions and duplications of whole exons (exon CNVs) is a key requirement of genetic testing. Accurate detection of this variant type has proved very challenging in targeted next-generation sequencing (NGS) data, particularly if only a single exon is involved. Many different NGS exon CNV calling methods have been developed over the last five years. Such methods are usually evaluated using simulated and/or in-house data due to a lack of publicly-available datasets with orthogonally generated results. This hinders tool comparisons, transparency and reproducibility. To provide a community resource for assessment of exon CNV calling methods in targeted NGS data, we here present the ICR96 exon CNV validation series. The dataset includes high-quality sequencing data from a targeted NGS assay (the TruSight Cancer Panel) together with Multiplex Ligation-dependent Probe Amplification (MLPA) results for 96 independent samples. 66 samples contain at least one validated exon CNV and 30 samples have validated negative results for exon CNVs in 26 genes. The dataset includes 46 exon CNVs in BRCA1, BRCA2, TP53, MLH1, MSH2, MSH6, PMS2, EPCAM or PTEN, giving excellent representation of the cancer predisposition genes most frequently tested in clinical practice. Moreover, the validated exon CNVs include 25 single exon CNVs, the most difficult type of exon CNV to detect. The FASTQ files for the ICR96 exon CNV validation series can be accessed through the European-Genome phenome Archive (EGA) under the accession number EGAS00001002428.


Author(s):  
Rishab Bharadwaj ◽  
Thulasi Raman ◽  
Ravikumar Thangadorai ◽  
Deenadayalan Munirathnam

Hereditary hemolytic anemias present a unique diagnostic challenge due to their wide phenotypic and genotypic spectrum. Accurate diagnosis is essential to ensure appropriate treatment. We report two cases, which presented as hemolytic anemias, but initial workup was inconclusive and they were finally diagnosed with the help of Next Generation Sequencing (Dehydrated Hereditary Stomatocytosis and Kӧln Hemoglobinopathy). The introduction of gene sequencing to aid diagnosis of these disorders is a revolutionary step forward and should be incorporated earlier in the workup of such patients.


mSphere ◽  
2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Madolyn L. MacDonald ◽  
Shawn W. Polson ◽  
Kelvin H. Lee

ABSTRACT Adventitious agent detection during the production of vaccines and biotechnology-based medicines is of critical importance to ensure the final product is free from any possible viral contamination. Increasing the speed and accuracy of viral detection is beneficial as a means to accelerate development timelines and to ensure patient safety. Here, several rapid viral metagenomics approaches were tested on simulated next-generation sequencing (NGS) data sets and existing data sets from virus spike-in studies done in CHO-K1 and HeLa cell lines. It was observed that these rapid methods had comparable sensitivity to full-read alignment methods used for NGS viral detection for these data sets, but their specificity could be improved. A method that first filters host reads using KrakenUniq and then selects the virus classification tool based on the number of remaining reads is suggested as the preferred approach among those tested to detect nonlatent and nonendogenous viruses. Such an approach shows reasonable sensitivity and specificity for the data sets examined and requires less time and memory as full-read alignment methods. IMPORTANCE Next-generation sequencing (NGS) has been proposed as a complementary method to detect adventitious viruses in the production of biotherapeutics and vaccines to current in vivo and in vitro methods. Before NGS can be established in industry as a main viral detection technology, further investigation into the various aspects of bioinformatics analyses required to identify and classify viral NGS reads is needed. In this study, the ability of rapid metagenomics tools to detect viruses in biopharmaceutical relevant samples is tested and compared to recommend an efficient approach. The results showed that KrakenUniq can quickly and accurately filter host sequences and classify viral reads and had comparable sensitivity and specificity to slower full read alignment approaches, such as BLASTn, for the data sets examined.


2021 ◽  
Author(s):  
Shuna Luo ◽  
Zanzan Wang ◽  
Xiaofei Xu ◽  
Lan Zhang ◽  
Shengjie Wang ◽  
...  

Abstract Background: Myeloproliferative neoplasms (MPNs) include three classical subtypes: polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Since prefibrotic primary myelofibrosis (pre-PMF) was recognized as a separate entity in the 2016 revised classification of MPN, it has been a subject of debate among experts due to its indefinite diagnosis. However, pre-PMF usually has a distinct outcome compared with either ET or overt PMF. In this study, we examined the clinical, haematologic, genetic, and prognostic differences among pre-PMF, ET, and overt PMF.Methods: We retrospectively reviewed the clinical parameters, haematologic information, and genetic mutations of patients who were diagnosed with pre-PMF, ET, and overt PMF according to the WHO 2016 criteria using next-generation sequencing (NGS).Results: Pre-PMF patients exhibited higher leukocyte counts, higher LDH values, a higher frequency of splenomegaly, and a higher incidence of hypertension than ET patients. On the other hand, pre-PMF patients had higher platelet counts and haemoglobin levels than overt PMF patients. Molecular analysis revealed that the frequency of EP300 mutations was significantly increased in pre-PMF patients compared with ET and overt PMF patients. In terms of outcome, male sex, along with symptoms including MPN-10, anaemia, thrombocytopenia, and KMT2A and CUX1 mutations, indicated a poor prognosis for PMF patients.Conclusion: The results of this study indicated that comprehensive evaluation of BM features, clinical phenotypes, haematologic parameters, and molecular profiles is needed for the accurate diagnosis and treatment of ET, pre-PMF, and overt PMF patients.


2021 ◽  
pp. 109352662110433
Author(s):  
Mikako Warren ◽  
Nishant Tiwari ◽  
Sabrina Sy ◽  
Gordana Raca ◽  
Ryan J Schmidt ◽  
...  

Background The hallmark of lipoblastoma is a PLAG1 fusion. PLAG1 protein overexpression has been reported in sporadic PLAG1-rearranged lipoblastomas. Methods We evaluated the utility of PLAG1 immunohistochemical staining (IHC) in 34 pediatric lipomatous tumors, correlating the results with histology and conventional cytogenetics, FISH and/or next generation sequencing (NGS) results. Results The study included 24 lipoblastomas, divided into 2 groups designated as “Lipoblastoma 1” with both lipoblastoma histology and PLAG1 rearrangement (n = 16) and “Lipoblastoma 2” with lipoblastoma histology but without PLAG1 cytogenetic rearrangement (n = 8), and 10 lipomas with neither lipoblastoma histology nor a PLAG1 rearrangement. Using the presence of a fusion as the “gold standard” for diagnosing lipoblastoma (Lipoblastoma 1), the sensitivity of PLAG1 IHC was 94%. Using histologic features alone (Lipoblastoma 1 + 2), the sensitivity was 96%. Specificity, as defined by the ability to distinguish lipoma from lipoblastoma, was 100%, as there were no false positives in the lipoma group. Conclusions Cytogenetics/molecular testing is expensive and may not be ideal for detecting PLAG1 fusions because PLAG1 fusions are often cytogenetically cryptic and NGS panels may not include all partner genes. PLAG1 IHC is an inexpensive surrogate marker of PLAG1 fusions and may be useful in distinguishing lipoblastomas from lipomas.


2020 ◽  
Vol 21 (4) ◽  
pp. 1290
Author(s):  
Jennifer S. Winn ◽  
Zachary Hasse ◽  
Michael Slifker ◽  
Jianming Pei ◽  
Sebastian M. Arisi-Fernandez ◽  
...  

We studied genomic alterations in 19 inflammatory breast cancer (IBC) patients with advanced disease using samples of tissue and paired blood serum or plasma (cell-free DNA, cfDNA) by targeted next generation sequencing (NGS). At diagnosis, the disease was triple negative (TN) in eleven patients (57.8%), ER+ Her2- IBC in six patients (31.6%), ER+ Her2+ IBC in one patient (5.3%), and ER- Her2+ IBC in one other patient (5.3%). Pathogenic or likely pathogenic variants were frequently detected in TP53 (47.3%), PMS2 (26.3%), MRE11 (26.3%), RB1 (10.5%), BRCA1 (10.5%), PTEN (10.5%) and AR (10.5%); other affected genes included PMS1, KMT2C, BRCA2, PALB2, MUTYH, MEN1, MSH2, CHEK2, NCOR1, PIK3CA, ESR1 and MAP2K4. In 15 of the 19 patients in which tissue and paired blood were collected at the same time point, 80% of the variants detected in tissue were also detected in the paired cfDNA. Higher concordance between tissue and cfDNA was found for variants with higher allele fraction in tissue (AFtissue ≥ 5%). Furthermore, 86% of the variants detected in cfDNA were also detected in paired tissue. Our study suggests that the genetic profile measured in blood cfDNA is complementary to that of tumor tissue in IBC patients.


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