mTOR inhibition in advanced renal cell carcinoma: which criteria should be used to evaluate therapeutic outcome?

With the implementation of mammalian target of rapamycin (mTOR) inhibitors in the systemic treatment of advanced renal cell carcinoma (RCC), considerable progress has been made regarding survival time and quality of life (QoL) compared with the treatment options used earlier. The prognostic factors used and the diagnostic measures taken to evaluate the oncological outcome and QoL of affected patients have not been adapted to this development adequately. This study analyses the recent phase III mammalian target of rapamycin inhibition trials for patients with metastatic RCC focussing on parameters for measurement of efficacy and QoL. It emphasizes the importance of adequate evaluation criteria for survival and QoL, as achieved by quality adjusted-time without symptoms and toxicity, in the palliative setting of advanced RCC.