Abstract
BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA), the second most common primary liver malignancy, accounts for 3% of gastrointestinal cancers. While surgical resection offers a five-year overall survival (OS) of 25-40%, only 12-30% of cases are resectable. Advanced or metastatic iCCA often necessitates systemic therapy combined with loco-regional treatments such as stereotactic body radiation therapy (SBRT). Despite its potential to improve local control (LC) and OS, the role of SBRT remains largely unexplored, particularly its integration with systemic therapy. This study evaluates the role of SBRT, with a focus on its combination with systemic therapy, in enhancing LC and OS in advanced/metastatic iCCA. METHODOLOGY: This retrospective analysis included 17 patients with advanced/metastatic iCCA treated between 2019 and 2024. Baseline characteristics, treatment regimens, and outcomes were obtained from electronic medical records. SBRT was administered in doses ranging from 30 to 50 Gy over 5-10 fractions. Follow-up assessments were conducted every three months to evaluate LC, disease progression, and survival. Statistical analyses, including Kaplan-Meier survival estimates, were performed using SPSS 23.0, with a P-value of <0.05 considered significant. RESULTS: The median follow-up was 14 months. The median OS was 21 months (95% CI: 14.5-27.4) from diagnosis, with one- and two-year OS rates of 90% and 30%, respectively. The median progression-free survival (PFS) was 10 months (95% CI: 8.1-11.8), with one- and two-year PFS rates of 35% and 15%, respectively. LC rates at one and two years were 92% and 70%, respectively. Gender significantly impacted OS, favoring female patients. Treatment was well tolerated, with no SBRT-related cholangitis or liver failure. CONCLUSION: SBRT appears to be a safe and potentially beneficial approach for advanced/metastatic iCCA, suggesting potential improvements in OS and PFS with minimal toxicity. This study highlights the potential of integrating SBRT with systemic therapies, particularly in patients with substantial tumor burden. Further prospective trials are necessary to validate these findings and refine SBRT protocols for advanced iCCA.