Consolidative Radiotherapy (CSRT) in Patients With Oligometastatic/Locally Advanced Unresectable Bilary Tract Cancer (BTC)

The purpose of this clinical trial is to investigate whether the inclusion of radiotherapy, in addition to standard-of-care systemic therapy, could improve the treatment effectiveness of patients with oligometastatic/locally advanced unresectable biliary tract cancer. The primary question that the trial aims to address is: does the addition of consolidative radiotherapy to standard-of-care systemic therapy for treating oligometastatic/locally advanced unresectable biliary tract cancer, result in a prolonged progression-free survival (PFS)? Researchers will assess whether radiotherapy can enhance PFS by comparing the survival time of patients with oligometastatic/locally advanced unresectable biliary tract cancer who receive standard-of-care systemic therapy alone versus those who receive standard-of-care systemic therapy along with consolidative radiotherapy. Participants in this trial will: Either receive or not receive consolidative radiotherapy following six cycles of standard-of-care systemic therapy.