Survival of patients with non-resectable, chemotherapy-resistant colorectal cancer liver metastases undergoing conventional lipiodol-based transarterial chemoembolization (cTACE) palliatively versus neoadjuvantly prior to percutaneous thermal ablation

Purpose: To determine overall (OS) and progression-free survival (PFS) for cTACE alone and in combination with percutaneous thermal ablation in patients with non-resectable, chemotherapy-resistant colorectal cancer liver metastases (CRLM). Material and methods: The study included 452 patients undergoing 2654 repetitive cTACE treatments of CRLM. 233 patients were treated palliatively using only cTACE, whereas 219 patients were treated with cTACE in a neoadjuvant intend with subsequent thermal ablation (either microwave ablation or laser-induced thermotherapy). The chemotherapeutics agents used, in either single-, double-, or triple-combinations, included MitomycinC, Gemcitabine, Irinotecan, and Cisplatin. Several factors were analysed to determine their prognostic value in terms of OS and PFS. Results: Palliative use of cTACE resulted in a median OS and PFS of 12.6 and 5.9 months, whereas the neoadjuvant use of cTACE showed a median OS and PFS of 25.8 and 10.8 months. The differences in OS and PFS between the two groups were statistically significant (p < 0.001). Extrahepatic metastases were a significant prognostic factor in the OS and PFS analysis of the palliative and neoadjuvant group. In addition, number, location, and mean size of metastases were significant prognostic factors for OS and PFS in the neoadjuvant group. Sex, primary tumor location, T- and N-parameters of the TNM staging system, time of liver metastases appearance, ablation method, and patient age did not significantly impact OS and PFS in either patient group. The most distinct response to cTACE was observed in metastases that were treated with a triple-combination of chemotherapeutics (p = 0.021). Conclusion: cTACE is an effective treatment option in advanced non-resectable CRLM. Chemoembolization followed by ablation further increases survival rates. A triple combination of chemotherapeutics improves response to cTACE.