Preoperative muscle steatosis is a novel prognostic predictor after hepatectomy for hepatocellular carcinoma

Abstract

Introduction: The quality of skeletal muscle, shown as muscle steatosis, has recently attracted much attention as a new parameter of sarcopenia, but its impact on outcomes after hepatectomy for hepatocellular carcinoma (HCC) remains unclear. Methods: We performed a retrospective analysis of 500 patients undergoing hepatectomy for HCC between April 2005 and March 2015. The quality and quantity of skeletal muscle were evaluated by intramuscular adipose tissue content (IMAC) and psoas muscle mass index (PMI) using preoperative CT imaging, respectively. Correlations of IMAC with other factors, overall and recurrence-free survival rates in patients classified according to IMAC or PMI, and risk factors for poor outcomes after hepatectomy were analyzed. Results: Patients with high IMAC showed older age (P < 0.001), higher body mass index (P < 0.001), higher indocyanine green retention test at 15 min (P = 0.048), and more operative blood loss (P = 0.019). The overall and recurrence-free survival rates were significantly lower in patients with high IMAC than in patients with normal IMAC (P < 0.001, P = 0.012, respectively). On the other hand, the overall and recurrence-free survival rates were not significantly different between high PMI and low PMI groups (P = 0.486, P = 0.307, respectively). On multivariate analyses, preoperative high IMAC was the significant risk factor for death (hazard ratio [HR] = 2.848; P < 0.001) and for HCC recurrence (HR = 1.383; P = 0.007) after hepatectomy. Conclusions: Preoperative muscle steatosis was closely correlated with postoperative mortality and HCC recurrence.