Value of urinary NMP-22 in patients with renal cell carcinoma

To investigate the preoperative and postoperative levels of urinary nuclear matrix protein-22 (NMP-22) in patients with renal cell carcinoma (RCC) and compare them with those of control patients. We also investigated and reported the relationship of NMP-22 with the pathologic grade and stage of RCC tumors. Urinary NMP-22 is currently used for monitoring patients with transitional cell carcinoma of the bladder.

The preoperative and postoperative urinary NMP-22 levels were measured in 23 patients with RCC and 20 control patients in whom solid renal masses were ruled out by either computed tomography or renal ultrasonography. The control group consisted of patients with benign conditions from the urology, gastroenterologic surgery, and cardiovascular surgery departments. Of the 23 patients with RCC, 21 underwent radical nephrectomy and 2 underwent partial nephrectomy.

The preoperative urinary NMP-22 levels were significantly higher in the RCC group than in the control group (10.65 +/- 5.49 U/mL and 4.64 +/- 3.10 U/mL, respectively, P <0.001). Ten days postoperatively, the urinary NMP-22 levels had decreased from 10.65 +/- 5.49 U/mL to 5.98 +/- 3.86 U/mL in the RCC group, which was statistically significant (P <0.001). The postoperative urinary NMP-22 levels were not different from those of the control group (5.98 +/- 3.86 U/mL versus 4.64 +/- 3.10 U/mL, P = 0.176).

The results of this study are promising for the use of urinary NMP-22 in the evaluation of patients who are at risk of RCC because the relationship between urinary NMP-22 and the presence of RCC has been shown.