Predictors of survival after surgical ablation of colorectal liver metastases

Abstract

Background: Local ablative therapy to treat colorectal liver metastases (CRLM) is shifting from palliative to curative intent, despite hard evidence to support its beneficial impact in curable patients. The aim of this monocentric retrospective cohort study was to analyze clinical and oncological outcomes after surgical ablation (SA) of CRLM, and to determine predictors of survival. Conclusions: Between 2003-2015 SA was performed in 321 consecutive patients (F/M ratio 121/200; median (range) age 63 (18-87) years) to treat 649 CRLM. SA was done via laparoscopy in 239 (74%), and combined with simultaneous colorectal and/or liver resection in 113 (36%) patients. Systemic chemotherapy was given in 206 (64%) before and in 179 (56%) patients after surgery. The impact of 14 prognostic factors on survival was evaluated using univariable and multivariable Cox regression models. Patients were followed up until death or until the date of study closure on November 2017, with a median follow-up time of 38 (0–158) months. Results: Postoperative complications occurred in 71 (22%) patients. Severe complications (TOSGS grade >3a) were observed in 26 (8%) patients, including 1 (0.3%) non-procedure related death. Median (95% CI) OS time was 52 (47–64) months and DFS 9.4 (8.3-10.5) months. OS and DFS rates at 5 and 10 years after surgery were 45.2% and 27.8%, and 14.4% and 13.7%, respectively. Independent predictors with negative influence on OS were the occurrence of de-novo CRLM (HR 3.631, CI 2.306-5.976, p<0.001), pre-operative chemotherapy (HR 1.960, CI 1.282-3.065, p=0.002), age >63y (HR 1.635, CI 1.144-2.352, p=0.007), and the presence of lymph node metastasis (pN) of colorectal cancer primary (HR 1.646, CI 1.095-2.546, p=0.016). Conclusion: Surgical ablation of CRLM provides survival rates similar to surgical resection. The occurrence of de-novo liver metastases is the predominant predictor of overall survival.