TEST:

Idylla™ MSI Test

Our prelimary data suggest that sAS discloses an immunosuppressive environment; therefore, compared to pAS, sAS might be a better candidate to immunotherapy.

MSIsensor scores as low as 3.5% may represent true MMRd in EC tested by NGS. Further testing for MMRd is advised for MSIsensor scores between 3% and 30%, particularly if there is low tumor content or associated high TMB. In this setting, MMR IHC may have superior sensitivity for detection of MMRd compared to DNA-based assays.

This new NGS-based MSI detection method outperforms previously published methods (i.e. Idylla, OncoMate MSI Dx, and Foundation One® CDx). Although highly efficient, Octaplex CaBio-MSID requires validation in a larger independent series of different tumor types.

"Biocartis...announces that it will host a free corporate workshop at the Annual Meeting of the ‘Association for Molecular Pathology’ (AMP), a leading molecular diagnostics conference, taking place between 14-18 November 2023 in Salt Lake City, Utah (US)."

The Idylla MSI Test is a clinically valid method for dMMR screening in CRC patients, and results of this testing can be used to guide further evaluation of individuals for Lynch syndrome. All percentage agreement point estimates used to determine the success of the study exceeded the 90% benchmark established a priori.

The TrueMark assay can detect the MSI status for tumor-only specimens with comparable performance to other PCR-based methods. The expanded number of monoallelic biomarkers leads to an increased number of MSI-L results, particularly in endometrial cancers; however, diagnostic specificity and accuracy were improved by implementing an MSI/MMR co-testing and Idylla confirmation testing strategy.

FGFR3 mutations were also more common in low stage tumors. This study expands on the clinicopathological spectrum of NUC and LNUC of the upper urinary tract and is the first to comprehensively analyze the molecular profile of these tumors, highlighting pathogenic genetic alterations of potential therapeutic and prognostic value.

Increasingly, MSI testing is a component of pan-solid tumor NGS panels allowing simultaneous determination of complex molecular signatures (e.g., MSI, tumor mutation burden) and detection of somatic variants. Despite the inherent challenges with MSI detection across different tumor types, methods for NGS-based MSI testing are reliable provided labs carefully establish and validate interpretation criteria.

In SS, these features included the presence of mucinous and/or solid components (P=0.034 and <0.001) and the presence of neutrophil-rich stroma, distant from tumor ulceration/perforation (P<0.001). In EB, both solid areas and extracellular mucin lakes were also discriminating features for the identification of MSI-high cases (P=0.002 and 0.045).

The Idylla MSI Test was successfully technically validated as an adequate tool for the evaluation of the MSI status in CRC.

IHC for MMR proteins represents an optimal screening tool for MSI status in GC. If resources are limited, isolated MLH1 evaluation may constitute a valuable option for preliminary screening. Idylla may help detect rare MSS cases with MMR-loss and define MSI status in indeterminate cases.

In this nationwide prospective study, MMR deficiency was rare in primary, surgically treated prostate cancer. This low prevalence contrasts with hospital-based studies of MMR deficiency and MSI that may have represented tumors with certain clinical features. The low prevalence and the need for an internal positive control for reliable scoring calls into question to what extent immunohistochemistry-based screening for MMR deficiency on limited tissue specimens, such as prostate biopsies, is routinely feasible.

Overall, we identified four discrepant cases of which three had tumor cell content less than 20%, explaining the discordant result. Our study shows that the Idylla MSI test offers a competent tool for MSI screening in CRC biopsy specimens.

"Biocartis Group NV...announces the U.S. Food and Drug Administration (FDA) 510(k) clearance for its fully automated Idylla™ MSI Test. This 510(k) clearance reinforces Biocartis’ commitment to enable clinical molecular diagnostics in the U.S. Now, labs of all sizes can benefit from Idylla™’s high sensitivity, unmatched ease-of-use, and rapid turnaround times."

NUC involving the UUT appears to be more aggressive than LNUC. The most frequent pathogenic mutation in both subtypes involve MT-CYB , which has not been previously reported. PIK3CA is significantly mutated in LNUC while FGFR3 mutations are more common in LNUC and is significantly associated with low stage tumors.

Corporate Presentation

"Biocartis Group NV...announces the publication of nine performance study abstracts of its fully automated molecular diagnostics Idylla™ platform and assays at the annual meeting of the ‘Association for Molecular Pathology’ (AMP), a leading molecular diagnostics conference, taking place between 1-5 November in Phoenix, Arizona (US). The studies were performed by a variety of US laboratories and research institutes."

The findings highlight challenges in MSI detection in endometrial cancer using PCR-based methods. The imperfect correlation between IHC for MMR and molecular MSI testing has been acknowledged. The automated rapid Idylla MSI assay yields negative results in more than 60% of dMMR endometrial cancer cases when manufacturer's instructions are followed.

High concordance rate was found when comparing EBs and SSs for MMR-status by IHC, suggesting that we can rely on the immunohistochemical evaluation of EBs when assessing GC cases before surgery/neoadjuvant chemotherapy. The few discord-ant cases (n=5) may be explained by insufficient tumour sampling to account for GC heterogeneity (4/5 had ≤2 EBs), and/or neo-adjuvant chemotherapy (used in 3/5 patients). Although IdyllaTM reliably evaluated MSI-status in SSs, as compared to gold-standard, it doesn't seem to accurately identify MSI-status in EBs.

Idylla™ MSI assayshows higher sensitivity than Pro-mega™ MSI analysis, in detecting MSI-H in MMRd EC. Promega™ misses isolated losses of MMR proteins. Probably, the selection criteria for MSI-H in Promega™ (more than one gene mutated) is the reason of the low agreement.

"Otherwise, HRM approaches and microcapillary electrophoresis platform failed to detect MSI-ECs showing minimal microsatellite shifts. In conclusion, whereas in colorectal site several technologies are eligible for MSI test, in ECs MSI test should be based on fluorescent capillary electrophoresis as it identifies a higher proportion of cases that could be misdiagnosed with other strategies."

Our findings support that the Idylla MSI assay provides a rapid, reliable, and ease-to-use solution to MSI detection in Chinese CRC patients with high sensitivity and specificity. The inconsistent cases between IHC and PCR-based approaches need a further analysis.

Corporate presentation

Several methodologies are frequently adopted in routine practice to successfully perform MMR/MSI status analysis. The most relevant issues related to MMR/MSI status analysis in MAs concern with low percentage of neoplastic cell and abundant mucine that may affect the molecular analysis. Thus, it might be useful to acquire both primary and metastatic sample to evaluate the MMR/MSI status by integrating IHC evaluation and molecular methodologies to successfully perform molecular profiling for MA patients.

"The Idylla™ MSI assay is a rapid and highly concordant test for MSI in EC. Modification of the Idylla™ scoring system could increase the sensitivity and specificity of the MSI assay for EC analysis."

"Our small sample size may be a limitation of the study. In our cohort, RAS-mutated tumours were associated with worse DFS and OS in early-stage CRC, whereas the remaining molecular variables had no prognostic influence."

Manual checking of microsatellite analyses results and confrontation between the results of Idylla and immunohistochemical analyses have permitted detection and correction of the discrepancies. The implementation of an in-house Idylla MSI testing for non-CRC tumors, necessarily combined with immunohistochemistry searching for MSI tumors, appeared not only valuable in terms of performances, but also in terms of cost-effectiveness without increasing the analyses-related costs but decreasing dramatically their turnaround times to one single working day.

In this article, we review the data about the fast and fully automated real-time PCR platform Idylla™ (Biocartis, Mechelen, Belgium) permitting the mutational analyses of BRAF, KRAS, NRAS, EGFR and microsatellite instability notably in melanoma, non-small-cell lung cancer and colorectal cancer samples. Future applications as well as the implementation of Idylla™ in the workflow of pathology and/or molecular biology laboratories are also discussed.

Correlation between IHC and molecular findings is heterogeneous, and determination between retained or lost expression of MMR proteins by IHC when HEP ooccurs, however feasible, does not represent the actual molecular alterations. Thus, molecular analysis should be performed every case to adequately determine the intrinsic features of each tumor. Due to the rarity of this finding, this is financially viable and has the potential to change clinical practice in a subset of patients.

The aim of our study was to investigate the use of TPs on the Idylla system to reduce TATs, such that results would be available with routine surgical pathology reports. Our approach of collecting TP samples directly from tissue and testing them via the Idylla system significantly reduced potential TATs. Samples processed with rapid intent often provided results the same day as or before the pathology report release.

The performance characteristics of Idylla are equivalent to Promega in determining MSI status of solid tumor specimens. Based on the results of this study, the Idylla platform was implemented in our laboratory and has significantly reduced the average turn-around time from 6 days to 3 days. In addition, fewer cases have been rejected due to not meeting the minimum sample requirements such as minimum tumor volume and availability of normal tissue.

The applicability of using an integrated approach to detection of somatic tumor variants and MSI status has great clinical utility for a variety of tumor types. In addition, paired normal tissue is not required for NGS using an expanded panel of mononucleotide markers.

Our data indicate a low incidence rate of MSI tumours in patients with UTUC. Furthermore, our findings highlight that Idylla MSI Assay can be applied as an alternative method of MSI analysis for UTUC.

The novel Idylla™ MSI Test showed high concordance in determining MSI status in non-CRC, with a good concordance in all the various tissue tested. The findings in our study support the use of this Test as an alternative method to detect MSI in non-colorectal cancers.

Discordant cases were analyzed using the Titano MSI kit. Overall, our data pinpointed a central role for molecular techniques in the diagnostic evaluation of dMMR/MSI-H status not only in CRC patients but also in other types of solid tumors.

Our results suggest that IHC is an efficient method to determine MMR status in ECs. However, the Idylla MSI assay is a rapid and reliable tool to define MSI status, and it could represent a valuable alternative to conventional MSI-PCR methods.

Idylla is more performant than PCR, for the detection of MSI in MTS-associated tumours and is a reliable additional technique to help detecting MTS in these tumours.

PCR, Idylla and NGS show similar diagnostic performance for dMMR detection in colorectal and endometrial cancers. Molecular MSI analysis has lower sensitivity for dMMR detection in endometrial cancer indicating that combined use of both IHC and molecular methods is recommended.Clinical Trial Number/IRB: B1172020000040, Ethical Committee, AZ Delta General Hospital.

Our study demonstrate the feasibility, but also the cost-effectiveness, of a multistep but rapid diagnostic strategy based on non-sequencing methods to identify rare and targetable kinase fusions in patients with advanced CRCs as well as the high prevalence of these kinase fusions in MLH1 MSI-High wild-type CRCs. Nevertheless, confirmatory RNA-sequencing analyses are necessary in case of low FISH positive nuclei percentage to rule out FISH false-positive results.

Conversely, the Idylla™ platform showed a significant variation in concordance rate with the IHC approach by considering a neoplastic cell percentage >50% (p-value = 0.002), and the TapeStation 4200 system showed a significant variation in concordance rate with the IHC approach by considering a DNA integrity number (DIN) ≥4 as cut-off (p-value = 0.009). Our data pinpoint a central role of the pre-analytical phase in the diagnostic outcome of MSI testing in CRC.

We also re-analyzed EC samples with variable tumor cellularity to determine the limit of detection of the Idylla test and found that a 30% or higher tumor cellularity is required. We conclude that Idylla MSI test offers a sensitive and specific method for CRC diagnostics but is less sensitive in EC samples especially in the case of MSH6 deficiency.

The present case reports for the first time, at the best of our knowledge, the coexistence of IPMN lesions and pancreatic medullary carcinoma, both having the same molecular alterations. It also describes the second case of pancreatic medullary carcinoma with microsatellite instability MSH2 and MSH6 silenced, the first having been described by Banville et al in 2006.