Evaluation of the Idylla system for rapid detection of POLE mutations in colorectal and endometrial cancers

Abstract

Pathogenic exonuclease domain mutations in POLE define a hypermutated subtype of colorectal and endometrial cancers, with prognostic and therapeutic implications, particularly for immunotherapy. Detection currently relies on next-generation sequencing, which is sensitive but costly and time-consuming. The Idylla™ POLE-POLD1 Mutation Assay (Biocartis) is a fully automated real-time PCR for rapid detection of hotspot mutations, but its performance has not been fully evaluated.We retrospectively analyzed a cohort of 40 patients to evaluate the performance of the Idylla™ assay. All tumors underwent targeted NGS of POLE exons 9-14. DNA from formalin-fixed paraffin-embedded tissue was analyzed with the Idylla™ assay and results were compared with NGS. The assay's limit of detection was also determined.The Idylla™ assay detected POLE hotspot variants with 96% sensitivity and 100% specificity. Limit of detection experiments indicated reliable detection only in samples with DNA concentration > 5 ng/µL and tumor cell content > 20%.The Idylla™ POLE-POLD1 Mutation Assay enables rapid, robust detection of POLE hotspot variants in colorectal and endometrial cancers, with high concordance to NGS. Integrating Idylla as a front-line screening tool could accelerate molecular classification, though NGS remains necessary for samples with low tumor content or low DNA input.

The authors' abstract, as published at the source. Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin, 2026 · DOI ↗