CSF1R and nonpapillary renal cell carcinoma: We identified 9 RTKs that were significantly phosphorylated in the primary ccRCC samples and 6 of which, Insulin R, HGFR, PDGFRβ, M-CSFR, VEGFR1, and VEGFR2, were specific to the ccRCCs samples comparing to their adjacent normal tissues.