Numerous molecular-targeted drugs have been developed based on the progress in the study of molecular biology. Among them, some of the antibodies and small molecule tyrosine kinase inhibitors have been approved for clinical use. Standard therapies against common cancers have completely been changed. Individualized treatments have been possible in pharmacogenomically specific populations. Unbelievably improved progression-free and/or overall survivals have been achieved and cure rate has also improved in surgically resected patients by using molecular-targeted therapy. Prognostic and/or predictive factors have been identified and biomarker testing has become mandatory for human epidermal growth factor receptor 2 expression/amplification in breast cancer and gastric cancer, Kras mutation in colon cancer and epidermal growth factor receptor mutation in lung cancer. The development of active molecular-targeted therapy and more validated markers could enable the increment of curative populations even in advanced malignancies.