The knowledge concerning the biology of the human tumors do not stop widening, in particular concerning the molecular mechanisms at the origin of the process of carcinogenesis and its ability to become perpetual. The identification and the increasing knowledge of these abnormalities allowed during these last years the development of therapeutic strategies targeting specifically the molecular pathways involved in the carcinogenesis. It quickly lead to numerous therapeutic successes in association with conventional chemotherapy, allowing a better individualization of the treatment according to the biological characteristics of the tumor of the patient.