What can molecular pathology offer for optimal decision making?

In recent years, colorectal cancer (CRC), once a uniform disease with well-understood carcinogenesis, has been divided into at least five different subgroups with distinct precursor lesions, pathways of carcinogenesis, morphological, and molecular characteristics. Moreover, new therapeutic concepts with 'targeted' substances have added to the complexity of the management of CRC patients. The clinical value of biomarkers in advanced CRC is indisputable ever since activating mutations of the KRAS oncogene have been shown to predict resistance to anti-epidermal growth factor receptor antibodies. Prognostic biomarkers predicting patient outcomes and predictive biomarkers forecasting response to a certain therapy may help us to improve therapeutic agent selection and patient management with the ultimate goal of maximizing the benefit of treatment and minimizing toxicity. Biomarkers with known implications in advanced CRC will be discussed in this paper.