Predictors of response to targeted therapy in renal cell carcinoma

Context.-The prognosis for patients with metastatic renal cell carcinoma is poor, with an average 5-year survival of approximately 10%. Use of traditional cytokine therapy, specifically high-dose interleukin 2, is limited by significant toxicity. Better understanding of themolecular pathogenesis of renal cell carcinoma has led to the development of targeted therapies to inhibit specific cellular pathways leading to tumorigenesis. These drugs provide improved survival with a more favorable toxicity profile. There is ongoing investigation of markers that predict response of an individual patient to different targeted therapies. Objective.-To explain the molecular basis for vascular endothelial growth factor inhibitor (antiangiogenic) and mammalian target of rapamycin inhibitor therapies for renal cell carcinoma, summarize the clinical trials demonstrating the effectiveness of these drugs, and describe the biomarkers shown to correlate with outcome in patients treated with targeted therapy. Data Sources.-All included sources are from peerreviewed journals in PubMed (US National Library of Medicine). Conclusion.-Emerging evidence shows promise that biomarkers will be useful for predicting an individual patient's response to targeted therapy, leading to a more personalized approach to treating renal cell carcinoma.