Longitudinal Changes in CT Body Composition in Patients Undergoing Surgery for Colorectal Cancer and Associations With Peri-Operative Clinicopathological Characteristics

There is evidence for the direct association between body composition, the magnitude of the systemic inflammatory response, and outcomes in patients with colorectal cancer. Patients with a primary operable disease with and without follow-up CT scans were examined in this study. CT scans were used to define the presence and changes in subcutaneous fat, visceral fat, skeletal muscle mass, and skeletal muscle density (SMD). In total, 804 patients had follow-up scans and 83 patients did not. Furthermore, 783 (97%) patients with follow-up scans and 60 (72%) patients without follow-up scans were alive at 1 year. Patients with follow-up scans were younger (p < 0.001), had a lower American Society of Anaesthesiology Grade (p < 0.01), underwent a laparoscopic surgery (p < 0.05), had a higher BMI (p < 0.05), a higher skeletal muscle index (SMI) (p < 0.01), a higher SMD (p < 0.01), and a better 1-year survival (p < 0.001). Overall only 20% of the patients showed changes in their SMI (n = 161) and an even lower percentage of patients showed relative changes of 10% (n = 82) or more. In conclusion, over the period of similar to 12 months, a low-skeletal muscle mass was associated with a systemic inflammatory response and was largely maintained following surgical resection.