Personalized Care in Colorectal Cancer

Colorectal cancer (CRC) is one of the most common cancers worldwide. Today, various techniques are available to detect CRC in its early stages or as precursor lesions, thereby preventing aggressive treatment. Approaching 60% of patients diagnosed with CRC will not die from the disease within the following five years. The range of drugs available to treat metastatic CRC is rapidly expanding and, in this area of cancer as in others, major advances are being made in our ability to assign specific treatments to subgroups of patients who are most likely to benefit.It has been needed to differentiate the individual characteristics of each tumor based on its biology as well as on the specific clinical situation. To understand the evolution of the disease, obtaining specimens of tumor tissue is crucial. This helps in optimizing the care of individual patients. It also enables us to develop more successful treatments in general by allowing the design of new clinical trials based on the molecular features of CRC.Typically, receptor-blocking drugs are large molecules based on our immune system and called monoclonal antibodies. The anti-EGFR monoclonal antibodies cetuximab and panitumumab are the two most important examples. The advantage of using drugs that target VEGF is that the need for blood vessels is common to all colorectal tumors.Even when a relevant molecular abnormality is identified, the subgroup of tumors which are positive on this test needs to be further dissected to establish which cancers among them are sensitive and which resistant to targeted drugs. And to truly personalize therapy for metastatic CRC, we may have to look not for the presence or absence of one, two or even three markers.The recent advances in molecular biology and the genetic classification of CRC are essential to individualize these therapies and will be basic for improving the treatment in the next years.