Current insights and future perspectives of treatment strategies for biliary tract cancer.

Biliary tract cancer (BTC) is a rare disease with few available treatment options. Tumor malignancy and surgical invasiveness vary depending on the site of the lesion. Perioperative mortality remains high, particularly in patients with hilar cholangiocarcinoma and gallbladder cancer. Benchmark cases from high-volume centers have reported high surgical complications (87%) and 3-month mortality rates (13%). Japanese studies of hepatopancreatoduodenectomy have reported that although the complication rate is higher in high-volume centers than in other institutions, the mortality rate is low; operative safety depends on adequate liver volume after resection by portal vein embolization, cholangitis reduction, and comprehensive management of postoperative complications. Robot-assisted surgery is increasingly common in patients treated with pancreaticoduodenectomy even after distal pancreatectomy. However, many challenges exist due to device and visibility issues. Recently, adjuvant chemotherapies have been developed for the treatment of BTC. The introduction of immune checkpoint inhibitors and discovery of oncogenic driver genes have increased the number of promising treatment options. Innovations in targeted drug therapy, including fibroblast growth factor receptor inhibitors and immune checkpoint inhibitors, have shown efficacy and broadened the treatment options for unresectable BTC. Therefore, a multidisciplinary treatment strategy based on surgical intervention is desirable.