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Mutations in the epidermal growth factor receptor (EGFR) are the most common targetable alterations in lung adenocarcinoma. To facilitate rapid testing, the Idylla EGFR assay was incorporated as a screening method before next-generation sequencing (NGS). Validation and experience using an in-house developed analysis pipeline, enhanced with a manual review algorithm is described. Results are compared with corresponding NGS results. In all, 1249 samples were studied. Validation demonstrated 98.57% (69/70) concordance with the reference methods. The limit of detection varied from 2% to 5% variant allele frequency for total EGFR quantitation cycle between 20 and 23. Of the 1179 clinical cases, 23.41% were EGFR-positive by Idylla. Concurrent NGS was successfully performed on 94.9% (799/842) requests. Concordance of Idylla with NGS was 98.62% (788/799) and 98.50% (787/799) using our in-house and Idylla analysis pipelines, respectively. Discordances involved missed mutations by both assays associated with low tumor/low input. Incorporating a manual review algorithm to supplement automated calls improved accuracy from 98.62% to 99.37% and sensitivity from 94.68% to 97.58%. Overall reporting time, from receipt of material to official clinical report, ranged from 1 to 3 days. Therefore, Idylla EGFR testing enables rapid and sensitive screening without compromising subsequent comprehensive NGS, when required. Automated calling, enhanced with a manual review algorithm, reduces false-negative calls associated with low tumor/low input samples.

TERTgene promoter mutations are known in multiple cancer types. Other TERTalterations remain poorly characterized. Sequencing data from 30,773 tumors analyzed by a hybridization capture next-generation sequencing assay (Memorial Sloan Kettering Cancer Center Integrated Mutation Profiling of Actionable Cancer Targets) were analyzed for the presence of TERTalterations. Promoter rearrangements (500 bases upstream of the transcriptional start site), hypermethylation (n= 57), and gene expression (n= 155) were evaluated for a subset of cases. Mutually exclusive and recurrent promoter mutations were identified at three hot spots upstream of the transcriptional start site in 11.3% of cases (−124: 74%; −146: 24%; and −138: <2%). Mutually exclusive amplification events were identified in another 2.3% of cases, whereas mutually exclusive rearrangements proximal to the TERTgene were seen in 24 cases. The highest incidence of TERTpromoter mutations was seen in cutaneous melanoma (82%), whereas amplification events significantly outnumbered promoter mutations in well-differentiated/dedifferentiated liposarcoma (14.1% versus 2.4%) and adrenocortical carcinoma (13.6% versus 4.5%). Gene expression analysis suggests that the highest levels of gene expression are seen in cases with amplifications and rearrangements. Hypermethylation events upstream of the TERTcoding sequence were not mutually exclusive with known pathogenic alterations. Studies aimed at defining the prevalence and prognostic impact of TERTalterations should incorporate other pathogenic TERTalterations as these may impact telomerase function.

Although in-vivo engraftment, expansion, and persistence of CAR T cells are pivotal components of treatment efficacy, quantitative monitoring has not been implemented in routine clinical practice. We describe the development and analytical validation of a digital-PCR (dPCR) assay for ultra-sensitive detection of CAR constructs post-treatment, circumventing known technical limitations of low partitioning platforms.