Challenges in Molecular Targeted Therapy for Gastric Cancer: Considerations for Effi cacy and Safety

The Cancer Genome Atlas Research Network recently proposed a molecular classifi cation for gastric cancer (GC) into four subtypes based on comprehensive evaluation. While the mechanisms of molecular targeted therapies in GC were confi rmed by multiple clinical studies, only a limited number of therapeutics for GC have been approved to date. In this systematic review of the available literature, we discuss the completed and ongoing clinical trials of molecular targeted therapies in patients with GC, with a focus on their effi cacy and safety. Results of recent studies clearly demonstrated that trastuzumab and ramucirumab, monoclonal antibodies (mAbs) against human epidermal growth factor receptor 2 (HER2) and vascular endothelial growth factor (VEGF), respectively, improved overall survival (OS) in GC with manageable safety profi les. Careful surveillance of ongoing clinical trials and timely profi ling and monitoring of genetic signatures are imperative to establish a strong foundation for precision medicine in GC.