Monoclonal antibodies in gastrointestinal cancers

Introduction: Among gastrointestinal cancers, colorectal and gastric neoplasms are the most frequent. The development of new targeted drugs improved the efficacy of systemic therapy in advanced stages of those malignancies. Areas covered: This review highlights the main biological processes implicated in gastrointestinal cancer development and progression, such as angiogenesis and epidermal growth factor receptor (EGFR) signaling pathway. On these bases, anti-EGFR and anti-vascular endothelial growth factor (VEGF) monoclonal antibodies in colorectal and gastric cancer are discussed. Data about further monoclonal antibodies in development are also reported. Expert opinion: The use of monoclonal antibodies in colorectal and gastric cancers showed the best outcomes when combined with chemotherapy, even though single agent anti-EGFR antibodies seem active in particular setting of metastatic colorectal cancer (CRC) patients. It is not well defined whether the addition of anti-VEGF and anti-EGFR to chemotherapy could improve outcome in those patients susceptible to CRC-related metastases resection. Little and conflicting data are available about the role of these drugs in adjuvant setting. Tests are available to select patients with higher probability to get benefit from these treatments. Further biomarkers need to be evaluated to improve this selection and achieve "tailorization" of systemic therapy. © 2013 Informa UK, Ltd.