[Renal tumor embolization].
We present an update on the technical aspects and clinical efficacy of the concept of capillary embolization for the treatment of renal cell carcinoma. In preoperative indications, it is shown that only this type of occlusion can safely achieve a reliable breakdown of the peritumor vasculature to meet the surgical requirements for excision of huge tumors associated with abundant retroperitoneal tributaries. In particular, in tumors infiltrating the renal vein and the vena cava, capillary embolization proved to be extremely helpful. In palliative embolization the concept achieved local and clinical efficacy comparable to nephrectomy when applied in patients free of metastatic disease. In palliative embolization of patients with metastatic disease, no change in the natural history was found. A new but still experimental concept is the combination of chemoperfusion and chemoembolization for tumor nodules in a solitary kidney and for reoccurring retroperitoneal tumors. The application of a coaxial system that features perfect maneuverability enables tumor treatment on the level of subsegmental vessels. The first short-term results seem to be promising. If definite proof of the validity of such a concept is to be obtained, however, further long-term research needs to be conducted on larger numbers of patients.