Contribution of diet, tumour volume and patient-related factors to weight loss in patients with colorectal liver metastases

Abstract

Background One of the difficulties in assessing the contribution of tumour-related factors to cancer cachexia is measurement of the extent of disease where dissemination to multiple organ sites has occurred. Methods In this study the extent of tumour (both tumour volume and increase in marker levels), diet and patient-related factors (appetite, metabolic hormones, immune activation, liver function and quality of life) were compared in patients with colorectal liver metastases who had lost at least 1 kg in body-weight (weight loss) and patients who had not lost 1 kg in body weight (stable weight) during the preceding month. Results Forty patients (22 men; 14 with weight loss) were studied. Liver metastasis volume was significantly greater in patients who lost weight than in those whose weight was stable (median (interquartile range) 1179 (245–1517) versus 119 (23–523) ml; P = 0·003). The prevalence of patients with raised levels of serum immune products was significantly greater in the weight loss group for soluble interleukin (IL) 2 receptor α (sIL2rα) (P = 0·03) and IL-6 (P = 0·05), but not for soluble tumour necrosis factor receptor 1 (sTNFr1) or neopterin. There were significant correlations between serum C-reactive protein and sIL2rα (rs = 0·68, P < 0·0001) and IL-6 (rs = 0·46, P = 0·008) but not sTNFr1 or neopterin levels. Significant differences in appetite, nausea, diet, energy intake, liver function tests and serum levels of metabolic hormones were not detected. Conclusion Weight loss in patients with colorectal liver metastases was not explained by changes in diet, quality of life, or hormones, but activation of the innate and incomplete activation of the acquired immune systems may be involved. Agents that attenuate either the acute-phase inflammatory response or T lymphocyte IL-2 receptor upregulation might reduce weight loss in patients with metastatic disease.