The value of plasma osteopontin levels as a predictive factor of disease stage and recurrence in patients with bladder urothelial carcinoma: A prospective study

This study was performed in order to determine the value of plasma osteopontin (OPN) levels as a predictive factor of disease stage and recurrence in patients with bladder urothelial carcinoma (UC). Data from 50 patients diagnosed to have bladder UC after transurethral resection of bladder tumor (TURBT) from 2009 to 2010 were evaluated prospectively. Blood tests were performed before and after TURBT, and plasma OPN levels were measured using enzyme-linked immunosorbent assay. Differences in OPN levels according to clinicopathologic variables were analyzed statistically. Significant differences in plasma OPN levels were observed between groups with and without muscle invasion (89.16 vs. 67.08 ng/mL, p = 0.041). Comparison according to tumor grade found no significant difference between high and low grade groups (p = 0.115). Mean plasma OPN levels decreased after TURBT without statistical significance (p = 0.571). Between groups with recurrence and those without recurrence, OPN levels of the group with recurrence were higher without statistical significance (p = 0.161). Comparison of plasma OPN levels according to performance of radical cystectomy (RC) showed significant differences; patients who underwent RC showed higher levels of plasma OPN (95.58 vs. 70.37 ng/mL, p = 0.030). Comparison according to T stage after RC showed significant differences in OPN levels (T1: 67.45, T2: 86.60 and T3: 95.23 ng/mL, respectively, p = 0.006). The group with lymph node invasion showed significantly higher levels of OPN, compared to the group without invasion (153.24 vs. 68.03 ng/mL, p = 0.017). Preoperative plasma OPN levels correlated to muscle invasion of bladder UC and pathological stage after RC.