Old tyrosine kinase inhibitors and newcomers in gastrointestinal cancer treatment.

Gastrointestinal cancer treatment is being based more and more on molecular biology, that has provided an increasing knowledge about cancer pathogenesis on which developing targeted therapy. Precisely, targeted therapy is defined a "type of treatment that uses drugs, such as monoclonal antibodies or tyrosine kinase inhibitors, to identify and attack specific cancer cells". Nowadays, many targeted therapies have been approved by the United States Food and Drug Administration for gastrointestinal cancers treatment, as many are in various phases of development as well. In a previous review we discussed the main monoclonal antibodies used and studied in gastrointestinal cancers. In addition to monoclonal antibodies, tyrosine kinase inhibitors represent another class of targeted therapy and following the approval of imatinib for gastrointestinal stromal tumours, others tyrosine kinase inhibitors have been approved for gastrointestinal cancers treatment such as sunitinib, regoragenib, sorafenib and erlotinib. Moving forward, the purpose of this review is to focus on the efficacy data of main tyrosine kinase inhibitors commonly used in the personalized treatment of each gastrointestinal tumours and to provide a comprehensive overview about experimental targeted therapies ongoing in this setting.