Is sarcopenia a better predictor of complications than body mass index? Sarcopenia and surgical outcomes in patients with rectal cancer.

Abstract

Sarcopenia, or a reduction of lean muscle mass, is associated with poorer outcomes in cancer patients. Few previous studies have examined this potentially correctable risk factor in patients with locally advanced rectal cancer. Skeletal muscle mass index was measured retrospectively on initial staging CT scans of patients undergoing chemoradiation followed by radical resection for rectal cancer for the period 2007-2013. Patients were categorized as sarcopenic or nonsarcopenic and differences in terms of demographics, pre-, peri- and postoperative outcomes were examined. Forty-seven patients were included; their mean age was 59.3 (36-82) years and 61.7% were men. We considered that 55.2% of men and 44.4% of women were sarcopenic; the overall prevalence of sarcopenia was 51.1%. Age, preoperative haemoglobin and albumin were significantly related to sarcopenia. Body mass index (BMI) and obesity (BMI > 30 kg/m² ) were not associated with sarcopenia. Blood transfusions were more frequent in sarcopenic patients (P = 0.001). Although readmissions and length of stay were not increased, overall postoperative complications were significantly higher in sarcopenic patients (P = 0.03). Neither BMI nor obesity was associated with postoperative complications. Sarcopenia was present in over 50% of patients with locally advanced rectal cancer at diagnosis. It was associated with a higher incidence of both blood transfusion and postoperative complications. BMI did not correlate with these negative outcomes. Sarcopenia may be a better predictor of surgical outcomes than BMI or obesity.