Non-alcoholic fatty liver disease may be a risk factor for liver metastasis after radical surgery for colorectal cancer: a retrospective study

Abstract

Abstract Background The liver is the most common site for distant colorectal cancer (CRC) metastasis, which develops in approximately one-third of CRC patients who undergo radical surgery. Hepatectomy for colorectal liver metastasis (CRLM) is the only potentially curative treatment for these patients. However, few metastatic CRC patients meet the criteria for this radical resection, and they have a low 5-year survival rate. Among those who undergo hepatectomy for CRLM, the recurrence rate is 60%. Thus, identifying risk factors for patients with CRLM is critical. One risk factor is non-alcoholic fatty liver disease (NAFLD), the incidence of which is increasing worldwide. NAFLD has become a main cause of chronic liver disease, and it is also an independent risk factor for CRC development. However, the effect of NAFLD on CRC liver metastasis after radical surgery remains unclear. The aim of this study was to retrospectively investigate the impact of NAFLD-associated hepatic fibrosis on liver metastasis after radical surgery for CRC. Methods We retrospectively analyzed data from 388 CRC patients with hepatic metastasis who underwent curative hepatectomy for CLRM at our hospital between April 2008 and March 2015. Data on each patient’s clinical results, surgical procedure, and postoperative course and their pathological and survival data were collected from our hospital records. The NAFLD fibrosis score (NFS) was also calculated, and patients were divided into two groups (NAFLD and non-NAFLD) on the basis of the NFS. Results Recurrence was observed in 83 (21.4%) of 388 patients after a mean follow-up 65.6 ± 15.1 months. Twenty-five patients had liver metastasis, and eight of them had NAFLD (8/45; 17.8%), while 17 of them (17/343; 5.0%) did not have NAFLD (p = 0.004). Additionally, liver metastasis-free survival in NAFLD patients was significantly worse than that in non-NAFLD patients (p < 0.001). We also showed that NAFLD and stage were independent risk factors for liver metastasis recurrence. Conclusions These results suggest that NAFLD may be a risk factor for liver metastasis in CRC patients who undergo curative surgery.