Defining the role of adjuvant therapy: cholangiocarcinoma and gall bladder cancer.

Biliary tract cancers are a rare subgroup of malignancies that include gall bladder carcinoma and cholangiocarcinoma. They generally carry a poor prognosis based on the advanced nature of disease at presentation and overall treatment refractoriness. Surgical resection remains the optimal treatment for long-term survival, with consideration of neoadjuvant or adjuvant therapies. In this review, we summarize the role of adjuvant treatments including radiation therapy, chemotherapy, and concurrent chemoradiation with the existing clinical evidence for each treatment decision. Given the rarity of these tumors, the evidence provided is based largely on retrospective studies, Surveillance, Epidemiological, and End Results (SEER) database inquiries, single- or multi-institutional prospective studies, and a meta-analysis of adjuvant therapy studies. Currently, there is no adjuvant therapy that has been agreed upon as a standard of care. Results from prospective, multi-institutional phase II and III trials are awaited, along with advances in molecular targeted therapies and radiation techniques, which will better define treatment standards and improve outcomes in this group of diseases.