NEPHRON SPARING SURGERY FOR RENAL-CELL CARCINOMA 4 CM. OR LESS IN DIAMETER - INDICATED OR UNDER TREATED

Purpose: Although radical nephrectomy is the standard treatment for lo calized unilateral renal cell carcinoma with a normal contralateral ki dney, there is ongoing interest in the use of nephron sparing surgery or partial nephrectomy in such cases. The extent of radical surgery in such cases has also been reconsidered in view of the uncertainty rega rding the malignant or benign nature. Materials and Methods: Of 14,793 autopsies in Jena from 1985 until 1995 there were 260 renal cell carc inomas. Of the 260 renal cell carcinomas the diameter was 40 mm. or le ss in 104. These 104 tumors were divided into group 1-20 mm. or less ( 33 cases), group 2-21 to 30 mm. (28) and group 3-31 to 40 mm. (43). Re sults: Grade 1 renal cell carcinomas decreased in frequency with incre asing tumor diameter, while an opposite result was noted for grade 3. Lymph node and distant metastases were well correlated with tumor size . With an increase in tumor size the frequency of venous involvement i ncreased as well. Significantly more multifocal malignant renal cell c arcinomas were seen in tumors between 21 and 40 mm. compared to those 20 mm. or less in diameter. Conclusions: The metastatic potential and biology of these small nodules are not yet known. To lower the risk of local recurrence the results of our study suggest that nephron sparin g surgery might be advisable in patients with renal cell carcinoma 20 mm. or less in diameter.