Many prognostic factors involving anatomical, histological and clinical aspects of the disease have been identified in RCC: the TNM staging system, tumor grade, sarcomatoid features, tumor size, performance status, etc.[2, 3] However, no satisfactory treatment options exist for patients with advanced RCC at present and the response rate to immunotherapy using interferon-α (IFN-α) and/or interleukin-2 (IL-2) is less than 20%.[4] Therefore, urologists cannot improve the prognosis in the present situation, even though they can know such traditional factors of their patients. The gene discussed is IL2; the disease is renal cell carcinoma.