In particular, urinary MMP-2 was detected in two (50%) oncocytoma specimens, with values of 0.58 and 4.11 ng/ml, respectively, and in 8/9 (89%) ccRCC samples (range, 0.72–3.41; mean ± SD, 1.4±1.0), whereas urinary MMP-9 was detected in only one (25%) oncocytoma specimen, with a value of 8.13 ng/ml, and in 6/9 (67%) of ccRCC patients (range, 0.55–22.8 ng/ml). This evidence concerns the gene MMP9 and nonpapillary renal cell carcinoma.