Locoregional Therapy for Intrahepatic Cholangiocarcinoma

SIMPLE SUMMARY: Intrahepatic cholangiocarcinoma is an aggressive primary liver cancer originating in the intrahepatic bile ducts. While surgical resection is the only curative treatment, many patients present with locally advanced, unresectable, or metastatic disease, and few are candidates for curative-intent resection. In this review, we examine locoregional therapy approaches and summarize the current literature. Current locoregional therapies include thermal ablation, transarterial chemoembolization, transarterial radioembolization, external beam radiotherapy, stereotactic body radiotherapy, hepatic arterial infusion of chemotherapy, irreversible electroporation, and brachytherapy. These therapies are most often offered to patients with unresectable primary or recurrent intrahepatic cholangiocarcinoma, and studies on each modality have shown these locoregional approaches to be effective for prolonging overall survival. The findings of this review also further inform the need for future research regarding the efficacy of these treatments in comparison to each other due to the limited literature on optimal treatment strategies. ABSTRACT: Intrahepatic cholangiocarcinoma (ICC) has a poor prognosis, and surgical resection (SR) offers the only potential for cure. Unfortunately, only a small proportion of patients are eligible for resection due to locally advanced or metastatic disease. Locoregional therapies (LRT) are often used in unresectable liver-only or liver-dominant ICC. This review explores the role of these therapies in the treatment of ICC, including radiofrequency ablation (RFA), microwave ablation (MWA), transarterial chemoembolization (TACE), transarterial radioembolization (TARE), external beam radiotherapy (EBRT), stereotactic body radiotherapy (SBRT), hepatic arterial infusion (HAI) of chemotherapy, irreversible electroporation (IE), and brachytherapy. A search of the current literature was performed to examine types of LRT currently used in the treatment of ICC. We examined patient selection, technique, and outcomes of each type. Overall, LRTs are well-tolerated in the treatment of ICC and are effective in improving overall survival (OS) in this patient population. Further studies are needed to reduce bias from heterogenous patient populations and small sample sizes, as well as to determine whether certain LRTs are superior to others and to examine optimal treatment selection.