Preoperative skeletal muscle fat infiltration is a strong predictor of poorer survival in gallbladder cancer underwent surgery

Recently, a decrease in skeletal muscle, termed sarcopenia, has been reported to be associated with poorer survival of patients in several types of cancer. However, few studies have investigated the association between sarcopenia and the survival of patients with gallbladder cancer.A total of 88 patients undergoing curative resection for advanced gallbladder cancer were included in this study. The quality of skeletal muscle was assessed by the intramuscular adipose tissue content (IMAC), and the quantity of skeletal muscle was assessed by the psoas muscle index (PMI), measured on preoperative computed tomography. The optimum cutoff values for IMAC and PMI for predicting the overall survival in each sex were determined using a minimum p value approach. Clinicopathological factors, IMAC and PMI were retrospectively analyzed to identify the predictors of overall survival (OS).The cutoff values for IMAC were -0.3 in males and 0.04 in females. The numbers of patients with low IMAC and high IMAC were 42 and 46, respectively. The cutoff values for PMI were 7.3 cm2/m2 in males and 5.0 cm2/m2 in females. The numbers of patients with low PMI and high PMI were 22 and 66, respectively. A multivariate analysis revealed that pT stage (pT3/4, hazard ratio [HR] = 6.72, p = 0.004), high IMAC (HR = 4.12, p < 0.001), Bile duct infiltration (present, HR = 2.82, p = 0.046), high age (≥72 years old, HR = 2.64, p = 0.010), major hepatectomy (performed, HR = 2.50, p = 0.031) and pN1/2 (HR = 2.17, p = 0.010) as independent prognostic factors.IMAC was independent prognostic factor for resected advanced gallbladder cancer, so the quality of skeletal muscle more strongly predicted survival than the quantity of skeletal muscle.