查看文章

Due to the approval of immune checkpoint inhibitor therapy for microsatellite instability-high or mismatch repair-deficient advanced solid tumors, testing of both biomarkers has gained interest in recent years. Available testing systems were established in the context of Lynch Syndrome for colorectal cancer, thus differences between microsatellite profiles across cancer types may lead to false data interpretation using validated tests for another tumor entity. The present study deals with challenges during microsatellite instability testing in endometrial cancer (EC) and provides a comprehensive comparative study of four different PCR-based approaches which could help to improve microsatellite instability (MSI) testing in future screenings. A validation strategy has been developed for the Idylla system, which can guide the method transfer to other tumor entities, and a screening procedure for EC has been proposed. By direct comparison, this study was able to highlight advantages and limitations of each system in an extensive manner.

Microsatellite instability (MSI), a common alteration in endometrial cancers (EC) is known as a biomarker for immune checkpoint therapy response alongside screening for Lynch Syndrome (LS). However, former studies described challenging MSI profiles in EC hindering analysis by using MSI testing methods intensively validated for colorectal cancer (CRC) only. In order to reduce false negatives, this study examined four different PCR-based approaches for MSI testing using 25 EC samples already tested for mismatch repair deficiency (dMMR). In a follow up …