Hepatic steatosis, body mass index and long term outcome in patients undergoing hepatectomy for colorectal liver metastases

BackgroundHepatic steatosis (HS) is as an independent risk factor for morbidity and mortality post-hepatectomy. Recent studies report significant correlation between chemotherapy (now frequently employed pre-hepatectomy for colorectal liver metastases (CRLM)), HS and steatohepatitis. Furthermore, raised body mass index (BMI) predisposes to HS. However, no previous study has analysed the effect of HS on long-term survival.MethodA retrospective analysis of a prospective consecutive cohort of 102 patients undergoing hepatectomy with 60 months follow-up data was performed. Resection specimens were examined histologically and the degree of steatosis graded accordingly. The data was compared to BMIs and other clinical characteristics. Statistical analyses included log-rank, contingency, logistic regression and Fisher's exact tests.ResultsNo detectable fatty change in 27 patients; 1 patient had cirrhosis; 57 had HS: 26 graded mild; 10 moderate, 21 severe and 17 not graded. 1 patient (BMI 29.5 kg/m2) had steatohepatitis but survived surgery. No significant difference in median survival between patients with and without HS (28.6 vs. 32.3 months, log-rank p > 0.05). Results were similar between patients with BMI < 25 and BMI ≥ 25 (32.3 vs. 36.8 months, log-rank p > 0.05). Analyses of BMI against steatosis grade showed that patients with a higher BMI were at an increased risk of having a more severe HS (logistic regression, p < 0.01; Fisher's exact, p < 0.01). Contingency analyses on the influence of diabetes, chemotherapy and increasing number of risk factors on the likelihood of obtaining HS were insignificant (Fisher's exact, all p > 0.05).ConclusionWhile patients with higher body mass index values are at increased risk of having more severe hepatic steatosis, neither BMI nor hepatic steatosis significantly influences long-term survival. We conclude therefore that neither obesity nor hepatic steatosis has significant prognostic relevance on long-term survival of CRLM patients undergoing hepatectomy.