Targeted approaches for treating advanced clear cell renal carcinoma

The mainstay of any curative treatment in renal cell carcinoma (RCC) is surgery. In the case of metastatic disease at presentation, a radical nephrectomy is recommended to good performance status patients prior to the start of cytokine treatment. Interferon (IFN)-a offers in a small but significant percentage of patients advantage in overall survival. Interleukin (IL)-2-based therapy gives similar survival rates. To date, hormonal therapy and chemotherapy do not have a proven impact on survival. Recent insights demonstrate that the majority of clear cell RCC harbor abnormalities of the von Hippel-Lindau (VHL) gene. This gene plays a key role in the stimulation of angiogenesis by vascular endothelial growth factor (VEGF) in this highly vascularized tumor. This opens interesting new treatment strategies including blockade of VEGF with the monoclonal antibody bevacizumab (Avastin) and inhibition of VEGF receptor tyrosine kinases with small oral molecules such as sunitinib (SU11248, Sutent) or PTK787. Likewise, inhibition of the Raf kinase pathway with oral sorafenib (Bay 43-9006, Nexavar) or inhibition of the mTOR pathway with intravenous CCI-779 are under investigation. Preliminary clinical results with all these compounds are promising, and the results of ongoing first-line phase III studies will become available in the next years.