Defining risk status in the first-line treatment of metastatic renal cell carcinoma.

Targeted agents, such as sunitinib, have significantly improved the prognosis of patients with metastatic renal cell carcinoma (mRCC) and are now well-established treatment options for these patients. Several pre-treatment clinical features have been associated with shorter survival, and identification of these prognostic factors has led to the development of risk models, such as the Memorial Sloan-Kettering Cancer Center (MSKCC) model. These risk models can be used to stratify patients according to their risk status. The risk status of patients can have important implications for their response to different treatment strategies; therefore, risk models enable treatment to be tailored for individual patients. In the MSKCC model, patients are stratified into one of three groups according to defined risk factors: favourable, intermediate or poor risk. The MSKCC model is well established and has been used to stratify patients in many clinical studies with targeted agents. However, some studies have used modified criteria which can make it difficult to make direct comparisons between studies. This can have important implications when selecting the most appropriate treatment for individual patients. In this review the rationale for establishing risk status is discussed and the practical application of risk models to aid the selection of appropriate first-line treatments is examined. Additionally, the evidence supporting the use of targeted agents in patients with mRCC according to their risk status is reviewed.