Inflammatory cytokines, appetite-regulating hormones, and energy metabolism in patients with gastrointestinal cancer.

This study investigated energy metabolism and its association with inflammatory cytokines and appetite- regulating hormones in patients with gastrointestinal cancer. Subjects were inpatients scheduled to undergo therapeutic intervention for diagnosed gastrointestinal cancer. Nutritional status on admission was assessed based on anthropometric measurements, nutrition screening results, food intake rate (energy intake/energy provided in hospital food), and biochemical test results. Fat-free mass (FFM) was measured using the bioelectrical impedance analysis. Resting energy expenditure (REE) and respiratory quotient were measured with indirect calorimetry, and basal energy expenditure (BEE) was calculated using the Harris-Benedict equation. A total 51 patients with gastrointestinal cancer were enrolled (17 with esophageal cancer, 15 with gastric cancer, and 19 with colorectal cancer); 16 had stage I disease, 11 had stage II, 13 had stage III, and 11 had stage IV. The levels of inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α increased significantly with cancer stage progression (P<0.001; Jonckheere-Terpstra trend test). The REE/body weight and the REE/FFM tended to increase with cancer stage progression (P=0.064 and P=0.053, respectively; Jonckheere-Terpstra trend test). FFM showed a significant negative correlation with the level of TNF-α (P=0.008; Spearman's correlation coefficient). Also, food intake rate showed a significant negative correlation with levels of IL-6 and TNF-α (P<0.001). The level of active ghrelin was positively correlated with that of IL-6 and energy metabolism (P=0.004 and 0.016, respectively) and negatively correlated with food intake rate (P=0.035), which suggests a state of ghrelin resistance. In conclusion, this study confirmed increases in the levels of inflammatory cytokines with the progression of gastrointestinal cancer and suggested the possible association of such increases with decreased FFM and the increased energy metabolism. However, the increased levels of active ghrelin failed to compensate for cachexia in cancer patients.