Association of low skeletal muscle index with increased systematic inflammatory responses and interferon γ-induced protein 10 levels in patients with colon cancer.

Abstract

BackgroundSkeletal muscle depletion is a prognostic factor in patients with cancer. Here, we evaluated the association between the skeletal muscle index (SMI) and local and systemic responses in patients with colon cancer.Patients and methodsWe analyzed the relationships of the SMI with neutrophil, lymphocyte, monocyte, and platelet counts; the neutrophil-to-lymphocyte ratio; albumin levels; and C-reactive protein levels in a cohort of 561 patients, and with the circulating levels of 39 cytokines in a cohort of 125 patients. We also studied the association between the SMI and tumor local inflammatory response and the effect of SMI on survival.ResultsThe median SMIs for male and female subjects were 44.1 and 34.2 cm2/m2, respectively. We observed positive correlations of the SMI with neutrophil (p=0.022), lymphocyte (p=0.001), and monocyte counts (p=0.003). A low SMI correlated significantly with an increased platelet count (p=0.017), decreased albumin level (p=0.006), neutrophil-to-lymphocyte ratio >3 (p=0.021), and an increased interferon γ-induced protein 10 level (IP-10, r = −0.276, p=0.002). The SMI did not correlate significantly with local inflammatory reactions or the C-reactive protein level. Finally, the SMI was a significant prognosticator in patients with stage III colon cancer (3-year disease-free survival rates: 35.1% for the low SMI arms versus 46.0% in the high SMI arms; HR =2.036; p=0.034).ConclusionThis study highlights the association of a low SMI with a high systematic inflammatory response and IP-10 levels. Furthermore, low SMI is a predictor of poor disease-free survival in patients with stage III colon cancer.