Furthermore, FGF18 expression significantly decreased with increasing tumor size (P = 0.011 < 0.05), as high FGF18 expression was noted in 22 of 49 ccRCC tumor size >3 cm (45%) cases and 21 of 33 ccRCC tumor size ≤3 cm (64%) cases. This evidence concerns the gene FGF18 and nonpapillary renal cell carcinoma.