PROBLEM TO BE SOLVED: To provide a method of sorting out patients to whom interleukin-2 (IL-2) and interferon alpha (IFN-alpha) concurrent treatment are effective for treating of renal cell carcinoma, and to provide a useful reagent and a useful reagent kit in order to easily carry out the above method.SOLUTION: Sensitivity of the patient over renal cell carcinoma IL-2 and IFN-alpha concurrent treatment is detected by the expression amount of either or both HLA-DQA1 gene and HLA-DQB1 gene as an indicator.