Objective: The purpose of this study was to evaluate the relationship between sarcopenia and overall and progression-free survival in patients with colorectal cancer.
Materials and methods: This study was retrospective and complied with HIPAA. Patients with colorectal cancer who underwent CT at the time of and 6-18 months after diagnosis were included. Patients were followed for at least 5 years after diagnosis. Skeletal muscle index (SMI) and mean muscle attenuation of the psoas and paraspinal muscles at the L4 level determined the degree of sarcopenia. Composite measurements combining psoas and paraspinal muscles (total muscle) were also obtained. Univariate and multivariate Cox proportional hazard analysis was performed to evaluate the association between survival and changes in SMI and changes in attenuation. Kaplan-Meier analysis was also performed.
Results: A total of 101 patients were included (mean age ± SD, 63.7 ± 13.7 years; 68 men, 33 women). The hazard ratios for overall survival were 2.27, 1.68, and 1.54 for changes in SMI of the psoas muscle, paraspinal muscle, and total muscle (all p < 0.05). The hazard ratios for overall survival were 1.14, 1.18, and 1.24 for changes in attenuation of the psoas muscle, paraspinal muscle, and total muscle, respectively (all p < 0.05). The hazard ratios for progression-free survival were 1.33, 1.41, and 1.23 for changes in SMI of the psoas muscle, paraspinal muscle, and total muscle (not statistically significant). The hazard ratios for progression-free survival were 1.10, 1.21, and 1.23 for changes in attenuation of the psoas muscle, paraspinal muscle, and total muscle, respectively (p < 0.05). Kaplan-Meier analysis showed significant differences in overall and progression-free survival based on sex-specific quartiles of muscle quantity and quality.
Conclusion: Progressive sarcopenia after diagnosis of colorectal cancer has a significant negative prognostic association with overall and progression-free survival.
Keywords: colorectal cancer; sarcopenia; survival.