This volume focuses on the clinical applications of molecular diagnosis and targeted therapy from the viewpoint of oncologists specializing in specific organs. In addition, it discusses the role of molecular diagnosis and targeted therapy in the course of surgical treatment. Recent, rapid advances in molecular biology have shed new light on the mechanisms of cancer progression, and molecularly targeted drugs have been used to treat a variety of malignant diseases. For the diagnosis and precise treatment of cancer, analysis of the molecular background of the tumor is indispensable. However, there are both tumor-specific and comprehensive mechanisms involved in these processes. Accordingly, a firm grasp of molecular