The homogeneous mutation status of a 22 gene panel justifies the use of serial sections of colorectal cancer tissue for external quality assessment

摘要: Testing for treatment related biomarkers in clinical care, like Ras mutation status colorectal cancer (CRC), has increased drastically over recent years. Reliable testing of these markers is pivotal optimal patients. Participation external quality assessment (EQA) programs an important element management and often obligatory to comply with regulations or accreditation. Formalin-fixed paraffin-embedded (FFPE) specimens would ideally form the basis assessments, as they represent most common starting material molecular testing. However, heterogeneity a lesion FFPE tissue block could potentially affect test results participating laboratories, which might compromise reliability results. To assess actual impact this potential problem, we determined 22 genes commonly mutated colon four levels covering 360 μm 30 blocks, by Next Generation Sequencing. In each block, genotype was identical at all levels, only little variation load. This result shows that selected CRC homogeneous within segment tumor. These data justify use serial sections, defined analysis.