Clinical biomarkers of response in advanced renal cell carcinoma.

There are now a range of effective targeted agents available for the first- and second-line treatment of advanced renal cell carcinoma (RCC). However, patients with advanced RCC have varied responses to therapy; some experience long-term responses while others may not respond, or even progress rapidly. Characteristics or markers that could be used to determine which patients will benefit most from which agent may enable us to select the optimal treatment of each individual patient, thereby improving efficacy and avoiding unnecessary toxic effects. These characteristics may be at the cellular or genetic level. Alternatively, the occurrence of adverse events may act as surrogate markers of a drug's on treatment activity, enabling prediction of outcomes during treatment. Recently, it has been suggested that during some targeted therapy for advanced RCC, the occurrence of specific adverse events, such as hypertension, hypothyroidism, hand-foot syndrome or fatigue/asthenia, may be associated with improved efficacy. This article reviews the evidence supporting clinical biomarkers in patients with advanced RCC receiving targeted agents. We also consider how these clinical biomarkers may affect the future management of patients with advanced RCC.