IL6 and cancer: This result was reasonable, because both two cytokines possess the property of pro-inflammatory15, 16, and inflammation is commonly occurred during the development and progression of cancer.The difference on plasma cytokines level between two groups can also attributed to the pain that cancer causes, an animal experiment showed that both IL-6 and IL-1β were elevated on the 3rd day after operation, and can change by the intensity of pain17.