This is a prospective, single-center, single-arm clinical study. It aims to evaluate the efficacy and safety of a new combination therapy as a first-line treatment for patients with advanced intrahepatic cholangiocarcinoma (ICC) who cannot be treated with surgery. The combined therapy includes hepatic arterial infusion chemotherapy (HAIC) with Liposomal Irinotecan, 5-Fluorouracil, and Leucovorin, along with the oral targeted drug Lenvatinib and an intravenous PD-1 inhibitor (an immunotherapy). A total of 30 participants will be enrolled. The main goal of the study is to measure the Objective Response Rate (ORR), which is the percentage of patients whose cancer shrinks or disappears after treatment.