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

Abstract

Background: Hepatic 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.

Method: A 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.

Results: No 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/m(2)) 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>or=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).

Conclusion: While 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.