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

Background: One of the difficuIties 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, irnmune activation, liver function and quality of tire) were compared in patients with colorectalliver metastases who had lost at least 1 kg in bodyweight (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) mi; P = 0'003). The prevalence of patients with raised levels of serum irnmune products was significantly greater in the weight loss group for soluble interleukin (IL) 2 receptor cx (sIL2rcx) (P = 0'03) and IL-6 (P = 0'05), but not for soluble tumour necrosis factor receptor 1 (sTNFrl) or neopterin. There were significant correlations between serum C-reactive protein and sIL2rcx (rs = 0'68, P < 0'0001) and IL-6 (rs = 0,46, P = 0'008) but not sTNFrl 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 colorectalliver metastases was not explained by changes in diet, quality of tire, or hormones, but activation of the innate and incomplete activation of the acquired irnmune systems mar be involved. Agents that attenuate either the acute-phase inflarnmatory response or T lymphocyte IL-2 receptor upregulation might reduce weight loss in patients with metastatic disease.