[The therapeutic potential of ablative radiotherapy for metastatic renal cell cancer: a tumour deemed radiation resistant].

: Image guided Stereotactic Body Radiation Therapy (SBRT), is a valuable alternative to other ablative approaches, especially in the context of metastatic renal cell carcinoma (mRCC). The efficacy of this treatment depends on the Biological Effective Dose (BED). The BED is determined by total dose and dose per fraction. The technical possibility of applying high dose per fraction (> 8-10 Gy), yielding a distinct biological response which is fundamentally different from the one observed with conventional irradiation, offers high response rates (80-90%) in a tumour which was historically considered "radio resistant". As a part of the increased radiobiological effect can be attributed to vascular catastrophe (endothelial apoptosis triggered by high fractional dose), there is a rationale to investigate association of SBRT and agents targeting tumour angiogenesis in mRCC in upcoming clinical trials.