The present study describes an optimized method for isolating peripheral blood circulating tumor cells (CTCs) and performing KRAS mutation analysis. The approach combines isolation of peripheral blood mononuclear cells and immunomagnetic labeling with CD45 and CD326 human microbeads with KRAS analysis performed with a Therascreen KRAS kit by quantitative PCR. KRAS mutations were detected in the CTCs of patients with metastatic colorectal cancer (mCRC). CTCs may represent an alternative to invasive procedures and their analysis may be representative of the current disease status of the patient. This proposed analysis may be performed in a daily clinical practice.
Keywords: KRAS gene; circulating tumor cells; inmunomagnetic labeling; metastatic colorectal cancer; peripheral blood.