title: Prognostic significance of platelet-derived growth factor receptor-β expression in localized clear cell renal cell carcinoma.
abstract: OBJECTIVE
  We investigated the expression status of vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF)-B and their receptors in organ-confined clear cell renal cell carcinoma (ccRCC) to evaluate their prognostic significance after radical surgery.
  
  
  METHODS
  In 758 consecutive patients diagnosed with pT1-2N0 ccRCC between 2007 and 2012, we prospectively investigated the expression levels of VEGF, PDGF-B, VEGF receptor (VEGFR) and PDGF receptor (PDGFR)-β via immunohistochemistry. Clinicopathologic parameters and expression of the angiogenic factors were analyzed with respect to recurrence-free survival (RFS) after nephrectomy. The median follow-up was 29.5 months (IQR 21.5, 39.6) after surgery.
  
  
  RESULTS
  Partial nephrectomy had been performed in 48.5 % of the patients, and tumors were staged as pT1a in 514 (67.8 %), pT1b in 192 (25.3 %) and pT2 in 52 (6.9 %). VEGF, PDGF and their receptors were identified in the cytoplasm and membranes of the tumor cells. Expression level of VEGFR inversely correlated with both tumor size (r = -0.076, p = 0.014) and nuclear grade (r = -0.297, p = 0.004). As for PDGF-B, the expression level showed an inverse correlation with tumor size (r = -0.216, p < 0.001) while PDGFR-β inversely correlated with nuclear grade (r = -0.341, p = 0.001). On multivariate analysis, age, pathologic stage, nuclear grade and PDGFR-β expression (high vs. low or none, HR 3.121 95 % CI 1.300-7.493, p = 0.011) were independently prognostic of RFS after nephrectomy.
  
  
  CONCLUSIONS
  In organ-confined ccRCC, high expression of PDGFR-β was independently predictive of poorer RFS after nephrectomy.
authors.affiliation: Department of Urology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, GyeongGi-Do, Korea.
authors.forename: Myungsun
authors.initials: M
authors.lastname: Shim
authors.affiliation: Department of Urology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea. cherynsong@amc.seoul.kr.
authors.forename: Cheryn
authors.initials: C
authors.lastname: Song
authors.affiliation: Department of Urology, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Korea.
authors.forename: Sejun
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Urology, School of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Seung-Kwon
authors.initials: SK
authors.lastname: Choi
authors.affiliation: Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Yong Mee
authors.initials: YM
authors.lastname: Cho
authors.affiliation: Department of Urology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Choung-Soo
authors.initials: CS
authors.lastname: Kim
authors.affiliation: Department of Urology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Hanjong
authors.initials: H
authors.lastname: Ahn
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D002292:Carcinoma, Renal Cell / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D007680:Kidney Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D009367:Neoplasm Staging; D009392:Nephrectomy / Q000401:mortality*; D011379:Prognosis; D011446:Prospective Studies; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000378:metabolism*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000378:metabolism; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D020797:Receptor, Platelet-Derived Growth Factor beta; D040262:Receptors, Vascular Endothelial Growth Factor
keywords: Platelet-derived growth factor; Prognosis; Receptor; Recurrence; Renal cell carcinoma; Vascular endothelial cell growth factor