Prognostic value of vascular endothelial growth factor (VEGF), VEGF receptor 2, platelet-derived growth factor-β (PDGF-β), and PDGF-β receptor expression in papillary renal cell carcinoma

The prognostic value of the expression of vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR2), platelet-derived growth factor (PDGF)-β, and PDGF receptor (PDGFR)-β in papillary renal cell carcinoma (pRCC) is unknown. A total of 145 patients, who were confirmed to have pRCC, were analyzed. Expression levels of molecular markers were assessed via immunohistochemistry. The median follow-up period for all patients was 52.0 (interquartile range, 34.5-90.5) months. Among the cohort of 145 patients, high VEGF expression was observed in 100 (69.0%) patients, whereas high expression of VEGFR2, PDGF-β, and PDGFR-β was observed in 64 (44.1%), 42 (29.0%), and 30 (20.7%) patients, respectively. Only patients with high VEGFR2 expression exhibited improved 10-year recurrence-free survival (85.3% versus 58.1%; P = .005) and cancer-specific survival (86.4% versus 70.1%; P = .014) rates compared with individuals who exhibited low expression. Multivariate analysis revealed that high VEGFR2 expression was an independent prognostic factor for recurrence (hazard ratio, 0.326; P = .006) and cancer-specific mortality (hazard ratio, 0.334; P = .046). During follow-up, 17 patients received targeted drug therapy. Patients with high VEGFR2 expression showed a better initial response (partial response, 40%; stable disease, 20%; progressive disease, 40%) than patients with low expression did (partial response, 0%; stable disease, 58.3%; progressive disease, 41.7%; P = .052). pRCC with high VEGFR2 expression seems to be associated with a better initial response to targeted drug therapy and a better prognostic outcome.