The impact of hepatic fibrosis on the incidence of liver metastasis from colorectal cancer

Background: The aim of this study was to clarify the influence of hepatic fibrosis on metachronous liver-specific recurrence in colorectal cancer (CRC) patients who underwent colorectal surgery with curative intent. Non-alcoholic steatohepatitis (NASH) is closely associated with hepatic fibrosis (HF). The number of patients who suffer from NASH is increasing because of the consumption of high-calorie diets. It remains unclear how much of an impact NASH and HF have on the development of liver metastasis in CRC. Methods: Patients who underwent curative surgical resection for CRC between 2000 and 2011 were included in this study. We evaluated the progression of HF by the non-alcoholic fatty liver disease fibrosis score (NFS) based on preoperative blood test results, age, body mass index, and diabetes mellitus. Patients were grouped according to high (fibrotic liver; FL) or low (normal liver; NL) NFS. The influence of HF on hepatic recurrence was assessed by survival analyses. Results: A total of 953 CRC patients were enrolled, comprising 293 in stage I, 327 in stage II, and 333 in stage III. The patients included were categorised as FL (77) or NL (876). The hepatic recurrence rates were 5.3% in the NL group and 10.4% in the FL group (P=0.02), whereas the overall recurrence rates were 16.0% in the NL group and 20.7% in the FL group (P=0.03). The 5-year liver-specific recurrence-free survival rate in the FL group was significantly poorer than that in the NL group (FL 89.1%, 95% confidence interval (CI) 78.4-94.7 vs NL 96.0%, 95% CI 94.3-97.2, log-rank test P<0.01). Multivariate analysis demonstrated that HF significantly promoted liver-specific recurrence compared with NL (HR=2.98, 95% CI 1.23-7.21; P=0.02). Conclusion: HF is a valuable prognostic factor for hepatic recurrence after curative surgical resection of CRC.