[Validation study of KRAS mutation in colorectal cancer].

There is no doubt that molecular targeted therapy has increasing importance in clinical oncology. Markers related to the molecular targets can help in the prediction of the antitumoral effect as well as in the positive or negative selection of patients. Such a marker is KRAS, since its mutation inhibits the effectiveness of anti-EGFR monoclonal antibodies in the treatment of advanced and/or metastatic colorectal cancer. To identify KRAS mutations different methods and techniques are available. A voluntarily performed study served to control the validity of our methods. As a result the 7 partcipating laboratories approached but not fulfilled (except one) the criteria set by EPS. A joint discussion helped to call the attention to some technical and financial problems. The key conditions to recognize mutational status of KRAS or other similar markers are the accredited laboratory for molecular diagnostics and the validated method. The improvement of the quality of such techniques is supported by the fact that more and more drugs can be used only after the obligatory measurement of relevant molecular target(s).