Renal (kidney) biopsy is performed to reveal the nature of a suspected lesion in the kidney. In the past, when a mass in the kidney was detected, classical approach was radical (complete) or partial removal of the kidney without performing a needle biopsy. However, since some of the kidney masses are benign, this practice may cause unnecessary kidney operations in some patients. This application, which has many drawbacks, is now largely abandoned and replaced by needle biopsy, as in other organs.
The needle biopsy in the kidney is usually performed under CT guidance, because most of the kidney masses found today are small and the small masses are much better seen with CT. After local anesthesia is applied to the skin and deep tissues, a needle is first advanced to the mass by seeing it on CT, and then a large number of biopsies are taken with a needle (trukat, cor biopsy needle) sent through this needle.
Once the kidney biopsy has been performed, it can be found out whether the mass is benign or malignant with over 95% accuracy. Most kidney tumors are renal cell carcinoma (RCC). While surgery was the only treatment in the past, percutaneous ablation methods, such as radiofrequency and cryoablation, are increasingly used today. Recent studies have shown that long-term outcomes of percutaneous ablation are the same as for surgery, but the complication rate is lower.