Abstract: ObjectiveTo investigate the roles of cytokine-induced killer (CIK) cells to treat localized renal cell carcinoma (RCC) patients after radical operation. Methods Overall 12 RCC patients with radical nephrectomy were assigned to 2 groups:（1）CIK therapy group included 8 cases, in which the CIK cells were infused into the patients in 15 days after operation.（2）Control group included 4 cases, in which biotherapy was not done. The follow-up duration was from 1 to 4 years after CIK treatment.The mononuclear cells were isolated from the peripheral blood of localized RCC patients after radical operation.The CIK were induced and cultured by CD3McAb、IL-2 and IFN-γ. Phenotype of CIK cells was identified by immuno-histochemistry technology.T lymphocyte subgroup activity in the peripheral blood was analyzed on day 7 and day 45. ResultsThe CIKs, also named CD3+ CD56+ NKT cells, were successfully induced from 0.75±0.89 to 30.25±3.06 (P<0.01) .Compared with the control group,the activity of CD3+、CD4+、CD8+、CD56+ cells in CIK group was increased(P<0.05).After CIK treatment, the total effective rates were 87.5% with 6 cases complete remission (CR), and 1 case partial remission.The adverse reactions such as fever,itching and edema were not observed.Four cases in control group were found metastasis in 2 to 15 months after operation. The medium survival of control group was 14.25 months (ranged from 5 to 34 months). ConclusionCIK cells treatment provided a safe and effective therapy method for localized renal carcinoma patients after operation.