Research progress in immune checkpoint inhibitors treatment of advanced biliary tract cancer

Biliary tract cancer is a highly lethal disease composed of diverse epithelial tumors, of which incidence is increasing. Nearly two‑thirds of patients with biliary tract cancer are in local advanced stage or metastasized at diagnosis. Systemic therapies are the primary treat-ment options, but the prognosis is poor. In recent years, the emergence of immune checkpoint inhibitors has changed the treatment prospects for advanced solid tumors, and multiple clinical trials and related studies have been conducted worldwide. Based on clinical experiences and pertinent researches in the field, the authors expound upon the research progress in immune checkpoint inhibitors treatment of advanced biliary tract cancer.