CeGaT GmbH is a provider of genetic diagnostics and NGS services for research and pharma customers. One big part of our diagnostic offerings is tumor diagnostics. In recent years, analyses starting from formalin-fixed or fresh frozen tumor tissue samples were complemented by analyses starting from cell-free DNA extracted from patient blood plasma obtained in "liquid biopsies".

These samples have several benefits for non-invasive monitoring. But they pose significant technical challenges as the amount of material is typically low and the percentage of tumor DNA in the total cell-free DNA fraction very low (<10%). Special wet-lab protocols and bioinformatics algorithms are required to provide sensitivity at these low amounts and allele frequencies. End-to-end validation of these processes is essential to ascertain performance characteristics such as specificity and sensitivity. However, such validations require well-defined control samples.

This talk will cover the difficulties labs face when trying to establish such standards on their
own, we will share our experience with a publicly available standard, present validation results and discuss some caveats.