Abstract
PURPOSE: This study aimed to evaluate whether the pathological findings from repeat transurethral resection of bladder (re-TURB) predict Bacillus Calmette-Guérin (BCG) response in patients with T1 high-grade bladder cancer. MATERIALS AND METHODS: We analyzed patients with bladder cancer enrolled in the prospective patient registry system of Seoul National University, SUPER-UC, from March 2016 to May 2022. Patients with T1 high-grade cancer who underwent re-TURB and BCG instillation were identified. Re-TURB pathology and its relationship with BCG response were analyzed. RESULTS: Out of a total of 2,673 patients with bladder cancer, 539 had T1 high-grade bladder cancer. Among these, 251 patients underwent subsequent re-TURB and BCG instillation. Of the 251 patients, 210 (83.7%) were male, and TURB was performed as the initial procedure in 232 cases (92.4%). In the TURB specimens of T1 high-grade cancer, concomitant carcinoma in situ (CIS), lymphovascular invasion, and variant histology were observed in 27 (10.8%), 54 (21.5%), and 29 (11.6%) cases, respectively. However, these factors were not associated with BCG failure after re-TURB. Re-TURB pathology showed chronic inflammation (51.8%), CIS (17.5%), Ta (15.5%), and T1 (15.1%). These findings were significantly correlated with BCG responsiveness. Notably, BCG failure was reported in 20.8% of patients with chronic inflammation, which showed the best response, compared to patients with T1 pathology, where BCG failure was observed in 47.4% of cases (p=0.011). CONCLUSIONS: The pathological results of re-TURB play a critical role in determining the BCG response in patients with T1 high-grade bladder cancer.