The prognostic impact of skeletal muscle status and bone mineral density for resected distal cholangiocarcinoma

Abstract

The preoperative body composition and bone mineral density (BMD) have been reported as prognostic factors for several cancers. However, the prognostic impact of the preoperative body composition and BMD for resected distal cholangiocarcinoma (DCC) remains unclear. A total of 111 patients who underwent pancreatoduodenectomy for DCC between 2002 and 2017 were analyzed. The skeletal muscle index (SMI) and BMD were measured by preoperative computed tomography. The optimal cut-off value of the body composition and BMD were selected based on the minimum P-value obtained by the log-rank test. The prognostic significance of the preoperative body composition and BMD was investigated using multivariate analysis. The median values of the SMI (45.7 vs. 36.7cm2/m2, P<0.001) and BMD (128.5 vs. 101.0 Hounsfield units [HU], P=0.005) in male and female were significantly different. The optimal cut-off values for the SMI were 55cm2/m2 in male and 36cm2/m2 in female, and those for the BMD were 75 HU in male and 74 HU in female. A multivariate analysis identified low SMI (hazard ratio [HR], 4.340; P=0.044), low BMD (HR, 5.333; P<0.001) and microscopic venous invasion (HR, 2.019; P=0.026) as independent prognostic factors for the survival. A preoperative low SMI and low BMD were independent prognostic factors for resected DCC.