In a murine colorectal carcinoma (CT-26) model of surgery-induced accelerated metastatic tumour growth, laparotomy was associated with a significant elevation in postoperative inflammatory cytokine levels specifically TNF-α and IL-6, compared to subjects undergoing laparoscopy or receiving anaesthesia alone (Shiromizu et al, 2000). This evidence concerns the gene IL6 and colorectal carcinoma.