Exploring the Efficacy and Safety of Tislelizumab in Combination With S-1 in the Treatment of Patients With Postoperative Recurrent High-risk Intrahepatic Cholangiocarcinoma

This study is testing whether combining the immunotherapy drug tislelizumab with an oral chemotherapy called S-1 after surgery can reduce the risk of intrahepatic cholangiocarcinoma (bile duct cancer inside the liver) returning, in patients who had surgery but still have one or more high-risk features that make recurrence more likely. **You may be eligible if...** - You are between 18 and 75 years old - You have bile duct cancer inside the liver that was surgically removed (complete or near-complete removal) - You have at least one high-risk feature: positive margins, multiple tumor nodules, spread to lymph nodes, cancer invasion around nerves, tumor larger than 5 cm, or blood vessel invasion - You have not received any chemotherapy, radiation, or immunotherapy in the 3 months before your surgery - Your liver function and organ tests are within acceptable ranges **You may NOT be eligible if...** - Scans before surgery showed distant spread (metastasis) - You received prior cancer treatment within 3 months before the operation - Your liver function is too impaired to tolerate treatment - Your organ function tests (blood counts, kidney, liver) do not meet minimum requirements Talk to your doctor to see if this trial is right for you.