Impact of preoperative quality as well as quantity of skeletal muscle on survival after resection of pancreatic cancer

Background. Skeletal muscle depletion, referred to as sarcopenia, is predictive of mortality in patients undergoing digestive operations. The impact of muscle quality on outcomes, however, is unclear. This retrospective study investigated the impact of preoperative skeletal muscle quantity and quality on survival in patients undergoing resection of pancreatic cancer. Methods. We investigated 230 patients who underwent resection of pancreatic cancer between 2004 and 2013. The quantity and quality of skeletal muscle, indicated by psoas muscle mass index (PM) and intramuscular adipose tissue content (IMAC), were measured in preoperative computed tomography images. Overall survival (OS) and recurrence-free survival (RFS) rates were compared according to PMI and IMAC, and prognostic factors after pancreatic resection were assessed. Results. The OS and RFS rates in patients with low PMI were lesser than in those with normal/high PMI (P < .001, P < .001), with a mean survival time of 17.7 and 33.2 months, respectively. The OS and RFS rates in patients with high IMAC also were less than in those with normal/low IMAC (P < .001, P = .003) (mean survival time = 21.5 and 56.5 months, respectively). Low PMI (low muscle mass) and high IMAC (low muscle quality) were independent prognostic factors of poor OS (hazard ratio [HR] = 1.999, P < .001; HR = 2.527, P < .001) and RFS (HR = 1.607, P = .007; HR = 1.640, P = .004), respectively. Conclusion. Preoperative sarcopenia, indicating low quality and quantity of skeletal muscle, is closely related to mortality after resection of pancreatic cancer