The complete pathological response after primary chemotherapy could represent an important prognostic factor in patients affected by colorectal liver metastases. In recent studies, increasing complete pathological response seems to be correlated with longer overall survival periods and it is recognized as an important prognostic factor in patients treated with pre-operative chemotherapy. The correlation of radiological information on residual neoplastic disease after neoadjuvant treatment, obtained with CT and PET, has to be evaluated; in fact the complete disappearance of liver metastasis on radiological imaging does not always mean a complete disappearance of tumor tissue on histological examination; when it is documented with surgical procedures and confirmed by pathologist's examination, we can consider the complete pathological response. In recent years the addition of monoclonal antibodies to conventional chemotherapy may further increase the proportion of patients referred for surgery; bevacizumab before surgery has been shown to be feasible and safe, although concerns still exist regarding possible post-surgical and wound healing complications or bleeding. The limitation of the radiologic assessment of response as a surrogate for pathological response is even more relevant when antiangiogenic treatments are used. Excellent responses to bevacizumab-containing regimens do occur and referral to surgical oncology is a crucial step for documentation of complete pathological response.