Survival Outcomes of Radiofrequency Ablation for Intrahepatic Cholangiocarcinoma from the SEER Database: Comparison with Radiotherapy and Resection.

Purpose: To determine effectiveness of radiofrequency ablation for treatment of intrahepatic cholangiocarcinoma (iCCA) using a population-based database.

Materials and methods: Data was extracted from Surveillance, Epidemiology, and End Results database from 2000 to 2020 to include 194 patients who underwent ablation for iCCA. Patient demographics, overall survival (OS), and cancer-specific survival (CSS) were retrieved. Factors associated with survival were evaluated. Comparison between ablation and surgical resection (n=2653) or external beam radiotherapy (n=1068) were performed.

Results: In the ablation group, atients diagnosed and treated after 2010 demonstrated improved OS than the 2000-2009 subgroup (mOS 32 versus 21 months, HR: 0.50 [95%CI: 0.33-0.75], p=0.001). Additional factors associated with OS included tumor size (≤3cm versus >3cm, p=0.049) and tumor stage (p<0.001). For patients diagnosed after 2010, the 1-, 3-, and 5-year OS were 82.8% (95%CI: 74.8-88.4%), 43.5% (95%CI: 33.5-53.1%), and 23.7% (95%CI: 15.3-33.5%), respectively. Patients with local disease (1-year OS: 87.8% [95%CI: 78.6-93.3%]) demonstrated improved OS than regional (1-year OS: 81.3% [95%CI: 52.5-93.5%]) and distant disease (50.2% [95%CI: 34.0-78.8%], p<0.001). For tumors ≤3cm, ablation and surgical resection offered comparable survival benefits (p=0.561), although both were better than radiotherapy (p<0.0001).

Conclusion: Survival of iCCA patients who underwent thermal ablation has improved over the last 10 years. For tumors ≤3cm, ablation could be as effective as resection with careful candidate selection, and may be considered as front line compared to radiotherapy in certain patient populations. Patient selection based on tumor size and disease stage could improve survival outcomes.