PD-1 Antibody Plus GEMOX as Postoperative Adjuvant Therapy in Perihilar Cholangiocarcinoma

This study is testing whether combining a PD-1 immunotherapy antibody with a chemotherapy regimen (GEMOX: gemcitabine and oxaliplatin) after surgery can help prevent bile duct cancer (perihilar cholangiocarcinoma) from coming back in patients who had surgery with clear margins but positive lymph nodes, suggesting a higher risk of recurrence. **You may be eligible if:** - You are between 18 and 75 years old - You have perihilar cholangiocarcinoma (bile duct cancer near the liver hilum) and have undergone surgery with clean surgical margins (R0 resection) - Your pathology confirmed cancer in nearby lymph nodes - You have not received any systemic treatment for 6 months - Your ECOG status is 0 or 1 and your liver (Child-Pugh A) and blood counts are acceptable **You may NOT be eligible if:** - Your cancer was not fully resected, or has already recurred or spread - You have had another cancer previously - You are pregnant or breastfeeding - Your liver, kidney, thyroid, or blood count values do not meet the required minimums Talk to your doctor to see if this trial is right for you.