Testing for somatic mutations in JAK2, MPL, and CALR genes is a crucial element in the diagnosis of myeloproliferative neoplasms (MPNs). This may have inadvertently led to increased requests for testing to rule out MPN, including clinical situations with low pretest probability. This article examines JAK2, MPL, and CALR testing by next-generation sequencing (NGS) with the goal of formulating practical guidelines to make test use more efficient and effective. NGS results from 1482 patients tested between 2015 and March 2022 were retrieved, along with corresponding bone marrow biopsies and complete blood cell count results performed within 90 days before NGS, and 245 cases (16.5%) were positive for pathogenic variants in JAK2, MPL, or CALR genes. The findings showed an increase in the proportion of positive cases with patient age, and a statistically significant difference in red blood cell counts and platelet counts among patients with positive versus negative results. Using these factors, simple algorithms were constructed to predict positive results with a maximum sensitivity of 91%, while potentially eliminating 28% of negative test results. However, these models still failed to identify approximately 9% of patients with MPNs. Among these missed patients, many had either primary myelofibrosis or myelodysplastic syndrome/MPN. Considering a simple triage model to help guide MPN testing could represent a more cost-effective approach, particularly if missed patients could be further reduced.

Increased adoption of personalized medicine has brought comprehensive genomic profiling (CGP) to the forefront. However, differences in assay, bioinformatics, and reporting systems and lack of understanding of their complex interplay are a challenge for implementation and achieving uniformity in CGP testing. Two commercially available, tissue-based, in-house CGP assays were compared, in combination with a tertiary analysis solution in a research use only (RUO) context: the AVENIO Tumor Tissue CGP RUO Kit paired with navify Mutation Profiler (RUO) software and the TruSight Oncology 500 RUO assay paired with PierianDx Clinical Genomics Workspace software. Agreements and differences between the assays were assessed for short variants, copy number alterations, rearrangements, tumor mutational burden, and microsatellite instability, including variant categorization and clinical trial-matching (CTM) recommendations. Results showed good overall agreement for short variant, known gene fusion, and microsatellite instability detection. Important differences were obtained in tumor mutational burden scoring, copy number alteration detection, and CTM. Differences in variant and biomarker detection could be explained by bioinformatic approaches to variant calling, filtering, tiering, and normalization; differences in CTM, by underlying reported variants and conceptual differences in system parameters. Thus, distinctions between different approaches may lead to inconsistent results. Complexities in calling, filtering, and interpreting variants illustrate key considerations for implementation of any high-quality CGP in the laboratory and bringing uniformity to genomic insight results.

A noninvasive test for earlier detection of pancreatic cancer in individuals at higher risk is currently unavailable. To fill this void, we devised PancSure, a laboratory developed test in compliance with clinical regulations. PancSure is based on the protein biomarkers LYVE1 and REG1B, measured in urine by enzyme-linked immunosorbent assay, and commonly utilized serum/plasma CA19.9, with an updated version of the PancRISK algorithm for data interpretation. The test was validated in a cohort of 565 patients: 117 (21%) asymptomatic patients without any known pancreatic condition or malignancies, 242 (43%) symptomatic patients with benign pancreatic diseases and 206 (36%) confirmed cancers; 161 (77.5%) stages I-II and 45 (22.5%) stages III-IV. PancSure passed all specifications during analytical validation and distinguishes early-stage resectable cancer from asymptomatic individuals with AUC of 0.93 (0.89-0.97, 95% CI) and 85-90% sensitivity (SN) and 78-87% specificity (SP); from symptomatic patients with AUC of 0.86 (0.81-0.91, 95% CI) and 83-85% SN and 72-83% SP; and from all non-cancer patients (pooled controls) with AUC of 0.89 (0.84-0.93, 95% CI) and 83-85% SN and 78-87% SP. PancSure is a noninvasive clinical-grade test with a 48-hour turnover, ready for implementation without any costly instrumentation, thus providing a viable solution for the earlier detection of pancreatic cancer in at risk groups for improved patient care.

An amplicon-based targeted next-generation sequencing (NGS) assay for the detection of gene fusions in sarcomas was developed, validated, and implemented. This assay can detect fusions in targeted regions of 138 genes and BCOR internal tandem duplications. This study reviews our experience with testing on the first 652 patients analyzed. Gene fusions were detected in 238 (36.5%) of 652 cases, including 83 distinct fusions in the 238 fusion-positive cases, 10 of which had not been previously described. Among the 238 fusion-positive cases, the results assisted in establishing a diagnosis for 137 (58%) cases, confirmed a suspected diagnosis in 66 (28%) cases, changed a suspected diagnosis in 25 (10%) cases, and were novel fusions with unknown clinical significance in 10 (4%) cases. Twenty-six cases had gene fusions (ALK, ROS1, NTRK1, NTRK3, and COL1A1::PDGFB) for which there are targetable therapies. BCOR internal tandem duplications were identified in 6 (1.2%) of 485 patients. Among the 138 genes in the panel, 66 were involved in one or more fusions, and 72 were not involved in any fusions. There was little overlap between the genes involved as 5'-partners (31 different genes) and 3'-partners (37 different genes). This study shows the clinical utility of a next-generation sequencing gene fusion detection assay for the diagnosis and treatment of sarcomas.

α-1 Antitrypsin (AAT) is an acute-phase reactant with immunomodulatory properties that mainly inhibits neutrophil elastase. Low serum levels cause AAT deficiency (AATD), an underdiagnosed condition that predisposes to pulmonary and hepatic diseases. The SERPINA1 gene, which encodes AAT, contains >500 variants. PI∗Z and PI∗S alleles are the most diagnosed causes of AATD, but the role of the SERPINA1 haplotypes in AAT function remains unknown. SERPINA1 gene was PCR amplified from 94 patients with asthma, using primers with tails for indexing. Sequencing libraries were loaded into a MinION-Mk1C, and MinKNOW was used for basecalling and demultiplexing. Nanofilt and Minimap2 were used for filtering and mapping/alignment. Variant calling/phasing were performed with PEPPER-Margin-DeepVariant. SERPINA1 gene was 100% covered for all samples, with a minimum sequencing depth of 500×. A total of 75 single-nucleotide variants (SNVs) and 4 insertions/deletions were detected, with 45 and 2 of them highly polymorphic (minor allele frequency >0.1), respectively. Nine of the SNVs showed differences in allele frequencies when compared with the overall Spanish population. More than 90% of heterozygous SNVs were phased, yielding 91 and 58 different haplotypes for each SERPINA1 amplified region. Haplotype-based linkage disequilibrium analysis suggests that a recombination hotspot could generate variation in the SERPINA1 gene. The proposed workflow enables haplotype-aware genotyping of the SERPINA1 gene by nanopore sequencing, which will allow the development of novel AATD diagnostic strategies.

Circulating tumor DNA (ctDNA) quantification surpasses cancer antigen 15 to 3 for metastatic breast cancer surveillance. Clinical translation, however, is limited because of uncertainties about the optimal method and clinically valid ctDNA decision thresholds. Plasma-SeqSensei Breast Cancer IVD kit (PSS) is a novel assay for ctDNA molecular counting, detecting ≥0.06% variant allele fractions in AKT1, ERBB2, ESR1, KRAS, PIK3CA, and TP53. PSS was validated against droplet digital PCR (ddPCR) in 201 samples from 16 subjects with PIK3CA/TP53-mutated cancers, longitudinally sampled for a median of 93 (range, 18 to 113) weeks, three to five weekly. PSS and ddPCR ctDNA levels correlate significantly (Spearman ρ, 0.923; 95% CI, 0.898-0.941) across 0% to 43% variant allele frequency (VAF) range. PSS predicts 12-week progression with high clinical accuracy (area under the curve, 0.848; 95% CI, 0.790-0.894). PSS validates a previously developed ddPCR classifier: <10 copies/mL (0.25% VAF); excludes >100 copies/mL (2.5% VAF); and confirms progression, with negative predictive value (95% CI) of 83% (76%-88%) and positive predictive value (95% CI) of 91% (81%-96%) (weighted κ, 0.856; 95% CI, 0.797-0.915). PSS thus confirms robust clinical thresholds (10 to 100 copies/mL, 0.25% to 2.5% VAF) for metastatic breast cancer surveillance, using absolute molecular counting.

Medical exome sequencing pipelines consist of various preprocessing steps to prioritize credible causal variants before a pathologist or variant curation scientist manually interprets potential findings that are then reported to patients. The variant allele frequency (VAF), reported as the fraction of sequencing reads supporting a variant call, can be used to screen for technical artifacts, yet a specific filtering threshold has yet to be established. A total of 13,122 manually curated variants, sequenced from 289 patients using the Agilent SureSelect Focused Exome enrichment kit at the University of Kentucky Clinical Genomics laboratory from October 2019 to May 2023, were evaluated. Totals of 278 single-nucleotide polymorphisms (SNPs) and 3340 SNPs as technical artifacts are clinically reported. All reported variants had a VAF between 0.33 and 0.63, and 82% (2725/3340) of sequencing artifacts had a VAF of <0.33. It is proposed that removing SNPs in which the VAF is less than approximately 0.30 reduces manual curation time by approximately 20% while capturing all medically relevant variants in medical exome sequencing data sets.

Next-generation sequencing (NGS) has applications in research, epidemiology, oncology, and infectious disease diagnostics. Wide variability exists in NGS wet laboratory techniques and dry laboratory analytical considerations. Thus, many questions remain unanswered when NGS methods are implemented in laboratories for infectious disease testing. Although this review is not intended to answer all questions, the most pressing questions from a public health and clinical hospital-based laboratory perspective will be addressed. The authors of this review are laboratory professionals who perform and interpret severe acute respiratory syndrome coronavirus 2 NGS results. Considerations for pre-analytical, analytical, and postanalytical NGS will be explored. This review highlights challenges for molecular laboratory professionals considering adopting or expanding NGS methods.

Early detection of pancreatic cancer has been shown to improve patient survival rates. However, effective early detection tools to detect pancreatic cancer do not currently exist. The Avantect Pancreatic Cancer Test, leveraging the 5-hydroxymethylation [5-hydroxymethylcytosine (5hmC)] signatures in cell-free DNA, was developed and analytically validated to address this unmet need. We report a comprehensive analytical validation study encompassing precision, sample stability, limit of detection, interfering substance studies, and a comparison with an alternative method. The assay performance on an independent case-control patient cohort was previously reported with a sensitivity for early-stage (stage I/II) pancreatic cancer of 68.3% (95% CI, 51.9%-81.9%) and an overall specificity of 96.9% (95% CI, 96.1%-97.7%). Precision studies showed a cancer classification of 100% concordance in biological replicates. The sample stability studies revealed stable assay performance for up to 7 days after blood collection. The limit of detection studies revealed equal results between early- and late-stage cancer samples, emphasizing strong early-stage performance characteristics. Comparisons of concordance of the Avantect assay with the enzymatic methyl sequencing (EM-Seq) method, which measures both methylation (5-methylcytosine) and 5hmC, were >95% for all samples tested. The Avantect Pancreatic Cancer Test showed strong analytical validation in multiple validation studies required for laboratory-developed test accreditation. The comparison of 5hmC versus EM-Seq further validated the 5hmC approach as a robust and reproducible assay.

Clonal hematopoiesis (CH) and clonal cytopenia of undetermined significance (CCUS) are recently recognized diagnostic entities that serve as an independent risk factors for cardiovascular disease and myeloid malignancy. CH is an incidental finding, and evaluation of the incidence of CH/CCUS-associated mutations in solid tumor next-generation sequencing samples was undertaken to better understand the prevalence of mutations in this population. A retrospective review of clinical sequencing data for solid tumor malignancies diagnosed between February 2022 and April 2023 on next-generation sequencing data was performed. Cases were reviewed for variants in genes associated with CH/CCUS. Variant allele frequencies and other factors of the sequencing data were assessed for determining risk of CH/CCUS. A total of 2479 cases were evaluated during the study period. Of these, 29 cases demonstrated potential CH/CCUS-associated mutations, with a total of 33 variants identified. These were identified in a variety of tumor types, with gliomas being the most common. Significant cardiac histories were found in over half of cases identified, and few cases had abnormal blood counts. Detailed criteria for flagging variants as suspicious for CH and recommendations for these criteria as future guidelines for reporting are described. These variants are incidental findings that require more extensive follow-up or change in therapy management using a single institutional cohort.

Stratification of cancer into biologically and molecularly similar subgroups is a cornerstone of precision medicine. The Lund Taxonomy classification system for urothelial carcinoma aims to be applicable across the whole disease spectrum including both non-muscle-invasive and invasive bladder cancer. A successful classification system is one that can be robustly and reproducibly applied to new samples. However, transcriptomic methods used for subtype classification are affected by analytic platform, data preprocessing, cohort composition, and tumor purity. Furthermore, only limited data have been published evaluating the transferability of existing classification algorithms to external data sets. In this study, a single sample classifier was developed based on in-house microarray and RNA-sequencing data, intended to be broadly applicable across studies and platforms. The new classification algorithm was applied to 10 published external bladder cancer cohorts (n = 2560 cases) to evaluate its ability to capture characteristic subtype-associated gene expression signatures and complementary data such as mutations, clinical outcomes, treatment response, or histologic subtypes. The effect of sample purity on the classification results was evaluated by generating low-purity versions of samples in silico. The classifier was robustly applicable across different gene expression profiling platforms and preprocessing methods and was less sensitive to variations in sample purity.

Timely diagnosis of vertical Trypanosoma cruzi infections involves microscopy-based detection of circulating parasites from peripheral blood, which lacks sensitivity and is operator dependent. Consequently, most children born to T. cruzi-infected mothers are required to undergo serological testing after 9 months, which risks loss to follow-up. Alternatively, the loop-mediated isothermal amplification (LAMP) test for T. cruzi DNA offers high analytical and clinical performance and is easy to use in low-complexity laboratories. Recently, we optimized this technique using an ultrarapid DNA extraction method combined with the LAMP in dried blood spots (DBSs) on FTA cards. The procedure has been implemented in 10 public maternities across Paraguay, Bolivia, and Argentina, involving the training of 14 technicians. Operators' performance was evaluated using a standardized DBS testing panel for harmonization, including negative controls and DBS samples artificially contaminated with T. cruzi at 50 and 20 cells/mL. There was strong agreement (ĸ = 0.924) for controls and 50 cells/mL samples, and good agreement (ĸ = 0.718) across all testing panels, even at the detection limit of the test. A prospective study collected 306 DBSs from 222 newborns at birth and/or 2 months, detecting T. cruzi microscopically in four cases. LAMP identified eight positive cases and perfectly aligned with real-time PCR (ĸ = 1), demonstrating higher sensitivity than microscopic observation for early detection of infection in infants.

The low incidence of ovarian cancer (OC) dictates that any screening strategy needs to be both highly sensitive and highly specific. This study explored the utility of detecting multiple colocalized proteins or glycosylation epitopes on single tumor-associated extracellular vesicles from blood. The novel Mercy Halo Ovarian Cancer Test (OC Test) uses immunoaffinity capture of tumor-associated extracellular vesicles, followed by proximity-ligation real-time quantitative PCR to detect combinations of up to three biomarkers to maximize specificity and measures multiple combinations to maximize sensitivity. A high-grade serous carcinoma (HGSC) case-control training set of EDTA plasma samples from 397 women was used to lock down the test design, the data interpretation algorithm, and the cutoff between cancer and noncancer. Performance was verified and compared with cancer antigen 125 in an independent blinded case-control set of serum samples from 390 women (132 controls, 66 HGSC, 83 non-HGSC OC, and 109 benign). In the verification study, the OC Test showed a specificity of 97.0% (128/132; 95% CI, 92.4%-99.6%), a HGSC sensitivity of 97.0% (64/66; 95% CI, 87.8%-99.2%), and an area under the curve of 0.97 (95% CI, 0.93-0.99) and detected 73.5% (61/83; 95% CI, 62.7%-82.6%) of the non-HGSC OC cases. This test exhibited fewer false positives in subjects with benign ovarian tumors, nonovarian cancers, and inflammatory conditions when compared with cancer antigen 125. The combined sensitivity and specificity of this new test suggests it may have potential in OC screening.

Detection of cancer early, when it is most treatable, remains a significant challenge because of the lack of diagnostic methods sufficiently sensitive to detect nascent tumors. Early-stage tumors are small relative to their tissue of origin, heterogeneous, and infrequently manifest in clinical symptoms. Detection of their presence is made more difficult by a lack of abundant tumor-specific indicators (ie, protein biomarkers, circulating tumor DNA) that would enable detection using a noninvasive diagnostic assay. To overcome these obstacles, we have developed a liquid biopsy assay that interrogates circulating extracellular vesicles (EVs) to detect tumor-specific biomarkers colocalized on the surface of individual EVs. We demonstrate the technical feasibility of this approach in human cancer cell line-derived EVs, where we show strong correlations between assay signal and cell line gene/protein expression for the ovarian cancer-associated biomarkers bone marrow stromal antigen-2, folate receptor-α, and mucin-1. Furthermore, we demonstrate that detecting distinct colocalized biomarkers on the surface of EVs significantly improves discrimination performance relative to single biomarker measurements. Using this approach, we observe promising discrimination of high-grade serous ovarian cancer versus benign ovarian masses and healthy women in a proof-of-concept clinical study.

Structural variants (SVs) caused by chromosomal rearrangements in common fragile sites or long interspersed nuclear element (LINE) retrotranspositions are highly prevalent in colorectal cancer. However, methodology for the targeted detection of these SVs is lacking. This article reports the use of formalin-fixed paraffin-embedded targeted-locus capture (FFPE-TLC) sequencing as a novel technology for the targeted detection of tumor-specific SVs. Analysis of 29 FFPE colorectal tumor samples and 8 matched normal samples revealed tumor-specific SVs in 24 patients (83%), with a median of 2 SVs per patient (range, 1 to 21). A total of 104 SVs were found in the common fragile site-associated genes MACROD2, PRKN, FHIT, and WWOX in 18 patients (62%), and 39 SVs caused by three LINE transposable elements were found in 15 patients (52%). Tumor specificity of SVs was independently verified by Droplet Digital PCR of tumor tissue DNA, and their applicability as plasma circulating tumor DNA biomarkers was demonstrated. It was concluded that FFPE-TLC sequencing enables the detection of tumor-specific SVs caused by chromosomal rearrangements and LINE retrotranspositions in FFPE tissue. Therefore, FFPE-TLC sequencing facilitates the investigation of the biological and clinical effects of SVs using FFPE material from (retrospective) cohorts of cancer patients and has potential clinical applicability in the detection of SV biomarkers in the routine molecular diagnostics setting.

Mutation analysis provides confirmation of a clinical and radiological diagnosis of thanatophoric dysplasia types I and II (TD I and II). We developed a single multiplexed PCR and a single-nucleotide extension (SNE) assay to identify 14 common mutations causing 99% of TD I and TD II, including the challenging three adjacent mutations in the stop codon of exon 18 of the FGFR3 gene. The assay design also provides a solution for resolving SNE PCR product sizing using performance optimized polymer-7. The assay was validated using 37 previously characterized, de-identified patient samples representing the nine wild-types and 10 of 14 mutant genotypes. Four artificial templates were synthesized to mimic four TD I mutations not represented in the available patient samples. Fragment size and fluorophore channel for each SNE product from 10 samples and the four artificial templates were used to define bins and panels for analysis with GeneMarker version 3.0 and GeneMapper version 6.0 software. Allele calls (bin placement within the panels) were verified using the remaining 27 previously characterized samples. This TD I and II PCR and SNE assay is a robust multiplexed assay, streamlined, to identify 14 mutations in one single reaction. This assay has a shorter turnaround time in comparison to traditional Sanger or next-generation sequencing.