Osteopontin overexpression predicts poor prognosis of upper urinary tract urothelial carcinoma

ObjectivesStudies indicate overexpression of osteopontin (OPN) promotes carcinogenesis, progression and metastasis of multiple human malignancies. However, the function of OPN in urothelial carcinoma (UC) of the upper urinary tract has not been investigated. This study evaluates the clinical significance of OPN expression in upper urinary tract UC.Materials and methodsOne hundred and ten cases (median age = 64, range = 24–84 years) of renal pelvic or ureter UC were retrospectively reviewed in this study. OPN expression were evaluated by immunohistochemistry staining on paraffin-embedded section of the tumor and scored by two qualified pathologists.ResultsHigh OPN expression was found in 54 (49.1%) of the cancer specimens. OPN expression was not significantly correlated with tumor T stage (P = 0.761), N stage (P = 0.339) or grade (P = 0.349). However, OPN expression was differently expressed by gender (P = 0.012) and cancer location (P = 0.026). OPN expression did not correlate with bladder recurrence-free (P = 0.661) or extra-bladder recurrence-free (P = 0.787) survival, but high OPN expression was a significant predictor for cancer-specific survival (P = 0.014).ConclusionOur findings indicated that higher OPN expression is a potential biomarker to predict patient survival. Further study is necessary to investigate the role of OPN in the carcinogenesis of upper urinary tract UC.