Observational Study to Evaluate the Use of Targeted Therapies in Metastatic Colorectal Cancer

The purpose of this study is to evaluate, in terms of overall survival, the benefit of monoclonal antibodies in the start time of the diagnosis of advanced disease or administer a deferred basis after progression to treatment with chemotherapy alone. Initially expected target population was 1950 patients (pts), in 2015 protocol was ammended to 1028 patients, because the size was sufficient to evaluate the superiority of the use of monoclonal antibodies the start time of the diagnosis against deferred use, with HR of 0.8, power of 90% and an alpha of 0.05. Finally in July 2018, recruitment was completed with a total of 1104 patients enrolled.