Application of molecular targeted agents in comprehensive treatment of gastrointestinal cancer

Abstract

Targeted agents increase response rates and improved overall survival in treatment of metastatic gastrointestinal cancer. Therefore, physicians pay more attention to the role of targeted agents in treatment of local advanced gastrointestinal cancer. The clinical trials are ongoing to evaluate the efficacy of Trastuzumab in neoadjuvant treatment of local advanced gastric cancer with HER-2 gene over expression. Many studies reported Cetuximab plus chemotherapy as a conversion treatment improve R0 resection rates and prolonged overall survival of the patients with potentially resectable colorectal cancer liver metastasis with wild type KRAS gene status. A phase III( clinical trial is assessing the conversion efficacy of Bevacizumab in unresectable disease with KRAS gene mutation. Current evidence showed that neoadjuvant therapy of targeted agents did not prolong survival of patients with resectable liver metastasis. However, this is controversial. In neoadjuvant therapy of local advanced rectal cancer, Cetuximab did not improve the rates of pathological complete response in most of the phase II( trials. Furthermore, there are no phase III( trials to assess the role of Bevacizumab. Compared to chemotherapy alone for metastatic cancer, it is more important to evaluate the interaction and synergistic action of targeted agents, cytotoxic drugs, surgery and radiation, to make a scientific multidisciplinary model in comprehensive treatment of local advanced cancer.