[mRNA quantification. The next challenge in routine diagnostics]

The application of predictive biomarkers results in an increase in the response rates and overall survival of cancer patients. This had been shown impressively for the detection of mutations in the proto-oncogenes KRAS and EGFR for the application of anti-EGFR targeted therapies in metastatic colorectal carcinomas and non-small-cell lung cancer, respectively. This mutation detection is of a qualitative nature. In addition, predictive biomarkers are known for the use of the commonly administered chemotherapeutics 5-fluorouracil, platinum-containing complexes, and Irinotecan, which are normally identical to the targets of the therapeutic compounds. The determination of these predictive biomarkers also results in an increase in response rates and overall survival. However, this detection is done via the quantitative determination of mRNA expression levels, implying greater efforts in detection, knowledge of cut-off levels, and higher requirements for nationwide establishment.