Optimization of EGFR mutation detection by the fully-automated qPCR-based Idylla system on tumor tissue from patients with non-small cell lung cancer

Treatment with EGFR inhibitors is limited to patients with advanced/metastatic non-small cell lung cancer who have known EGFR mutations. Currently, patient care has to respond to several imperatives to make these inhibitors broadly available to all patients; fast and accurate detection of EGFR mutations by a sensitive and specific standardized cost-effective method, easy-to-implement in settings with limited expertise in molecular diagnostics. We evaluated the Idylla™ EGFR Mutation Assay (Biocartis) for the detection of EGFR mutations in archived formalin-fixed paraffin-embedded (FFPE) tumor samples from a series of 55 patients with lung adenocarcinoma and compared these results with those obtained by a pyrosequencing ISO-15189 accredited laboratory method. The comparison was made on both whole surgical tumor sections and on three artificially constructed small biopsies (∼1 mm) from the same FFPE blocks. Cost-effectiveness and turnaround time comparison between the two methods was performed. On both whole tissue sections and on biopsy cores, the Idylla™ and pyrosequencing had an agreement of 95% (52/55). The Idylla™ EGFR Assay produced results faster and more cost-effective than pyrosequencing. The Idylla™ system showed a good sensitivity and was cost-saving in our setting. Because of the easy workflow, the Idylla™ system has the potential to expand EGFR testing to more pathology laboratories in a reliable and fast manner.