Concordance and clinical significance of uncommon variants of bladder urothelial carcinoma in transurethral resection and radical cystectomy specimens

OBJECTIVE: To evaluate the concordance and prognostic role of histologic variants of bladder urothelial carcinoma in transurethral resection of bladder tumor (TURBT) and radical cystectomy (RC) specimens. METHODS: Clinicopathologic information available at the time of RC and follow-up data from 4110 RC specimens, collected between January 2000 and December 2009 at 17 tertiary referral centers were retrospectively analyzed and evaluated for the presence or absence of uncommon variants of bladder urothelial carcinoma. The presence or absence of uncommon variants of bladder urothelial carcinoma was evaluated on previous TURBT specimens of patients undergoing RC. Cox regression was used to assess the impact of these parameters on cancer-specific survival, and the Kaplan-Meier test for disease-free survival was plotted for survival estimate. RESULTS: Of 4110 patients, 579 were found to have uncommon variants of bladder urothelial carcinoma at RC (14.1%), whereas 266 (6.4%) at TURBT. A lack of agreement about uncommon variants was observed between TURBT and RC specimens in the entire population (P <.001). The presence of uncommon variants at TURBT was associated with an increased risk of pathologic upstage (hazard ratio, 3.24; confidence interval, 1.19-6.37; P <.003) and significant decrease in cancer-specific survival and recurrence-free survival (P <.001). CONCLUSION: Although the concordance of presence of uncommon histologic variants of urothelial bladder carcinoma between TURBT and RC is low, the presence of uncommon histologic variants of urothelial bladder carcinoma at TURBT is associated with a less favorable clinical outcome.