Prognostic and predictive response factors in colorectal cancer patients: between hope and reality.

Colorectal cancer (CRC) represents one of the most commonly diagnosed cancers worldwide. It is the second leading cause of cancer death in Western Countries. In the last decade the survival of patients with metastatic CRC has improved dramatically. Due to the advent of new drugs (irinotecan and oxaliplatin) and target therapies (i.e., bevacizumab, cetuximab and panitumab), the median overall survival has risen from about 12 mo in the mid nineties to 30 mo recently. Many questions needing of right collocations and more clearness still exist regarding the prognostic factors and the predictive factors of response to therapy. Despite advances in dosing and scheduling of chemotherapy in both adjuvant and advanced settings, and a greater emphasis on early detection, the outlook still remains poor for most patients. Molecular analyses have shown that the natural history of all CRCs is not the same. Individual patients with same stage tumours may have different long term prognosis and response to therapy. In addition, some prognostic variables are likely to be more important than others. Here we review the role of prognostic factors and predictive factors according to the recently published English literature.