Ablative Therapy for Unresectable Intrahepatic Cholangiocarcinoma: A Systematic Review and Meta-Analysis

Background: Intrahepatic cholangiocarcinoma (iCCA) is usually a fatal malignancy with rising incidence globally. Surgical resection currently remains the only curative treatment. However, as only a minority of iCCA is amenable to resection, new therapeutic modalities are needed. Our aims were to systematically review and perform a meta-analysis on the existing literature regarding the use of ablative therapies for iCCA and to assess their efficacy as a treatment modality by calculating pooled survival results and investigate associations between prognostic factors and survival. Methods: A comprehensive search of the PubMed database for relevant articles was performed. Studies assessing survival in patients with iCCA undergoing ablation were included. Data were extracted on patient, tumour and treatment characteristics and survival. Random effects meta-analysis was used to pool the data. Galbraith plots were used to investigate heterogeneity; bubble plots were formulated using regression-based meta-analysis. Results: A total of 10 studies were included in the final analysis, yielding an aggregate of 206 patients (69.5% males, median age: 51.2-72.5) and 320 tumours. Of all patients, 70.4% were recurrent cases of iCCA, and 29.6% were cases of primary iCCA. The median overall survival ranged from 8.7 to 52.4 months. Pooled 1-, 3- and 5-year survival rates were 76% (95% confidence interval: 68-83%), 33% (21-44%) and 16% (7-26%), respectively. No significant association was found between the median age, number of tumours or median tumour size and 1-year survival. Conclusions: Ablative therapies display promising potential as treatment modalities for iCCA. However, further research is necessary to validate these findings.