 BASIC RESEARCH Biomarkers It seems interesting to measure the different biological markers that could be modulated by this antiangiogenic therapeutic. Some of them are known as prognostic factors in the metastatic renal carcinoma, others are directly linked to the mechanism of action of Sunitinib. Due to the biopsy prior to treatment initiation and nephrectomy after treatment initiation, it will be possible to evaluate biomarkers modification and to assess the potential link with the tumour response. 