[Prognostic analysis of colorectal liver metastases treated by surgery combined with intraoperative radiofrequency ablation].

Objective: To investigate the clinical value of intraoperative radiofrequency ablation (RFA) in the treatment of colorectal liver metastasis (CLM). Methods: A retrospectively analysis of 187 patients with CLM who underwent liver resection with or without RFA from January 2009 to August 2016 in Department of Hepatobiliary Surgery, Cancer Hospital, Chinese Academy of Medical Sciences was performed. According to whether RFA was used intraoperatively, patients were divided into resection only group and combined treatment group. The clinical and pathological characteristics of the two groups were compared to explore factors influencing survival and recurrence. Imbalance of background characteristics between the two groups was further overcome by propensity score matching method (PSM). Results: The number of liver metastases (267), simultaneous liver metastases (100%), bilobar involvement (73.3%) and preoperative chemotherapy (93.3%) rates were significantly higher in the combined treatment group than those in the resection only group(471, 74.7%, 42.0% and 63.1%)(all P <0.05). In the combined treatment group, median overall survival (OS) was 25.7 months; and 3-year and 5-year OS were 47.9% and 28.8%, respectively. In the resection only group, the median survival time was 46.9 months; and 3-year and 5-year OS rate was 59.1% and 42.4%, respectively (χ(2)=4.579, P =0.034). Median disease-free survival (DFS) was 5.4 months in the combined treatment group, and 10.1 months in the resection only group (χ(2)=5.399, P =0.023). In multivariate analysis, intraoperative RFA was not an independent prognostic factor for OS and DFS ( HR =0.98, 95% CI: 0.47-2.08, P =0.965; HR =1.21, 95% CI: 0.71-2.07, P =0.465). After PSM, the median OS of the resection only and the combined treatment groups were 30.2 and 25.7 months (χ(2)=0.876, P =0.350). The median DFS in the two groups was 5.3 and 4.2 months, respectively (χ(2)=0.199, P =0.650). Conclusion: In patients with similar tumor burden, liver resection combined with intraoperative RFA for unresectable CLM can achieve long-term outcomes similar to hepatectomy alone for resectable CLM.