No Added Benefit of Systematic Bladder Biopsies after BCG Induction in High-Risk Non-Muscle-Invasive Bladder Cancer Optimally Managed

Abstract

Objectives: To evaluate the added detection benefit of routine transurethral biopsies after an induction course of intravesical Bacillus Calmette-Guérin (BCG) for high-grade NMIBC. Methods: We retrospectively included all patients who underwent white and blue light TURB, subsequent adjuvant induction scheme of BCG, followed by post-instillation biopsies. We excluded patients in whom a prior BCG induction course failed those with synchronous upper tract urothelial carcinoma, and those who did not receive the full 6-week course. A total of 62 patients met inclusion criteria and their records were analyzed. Cystoscopy findings, urine cytology and pathological results of transurethral biopsy were evaluated. Sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratios and diagnostic accuracy were calculated for cystoscopy and cytology separately and in combination. Results: After BCG, a total of 342 bladder biopsy were taken with a median of 5 (IQR 2) per case. The biopsy was positive in 13 patients (21%). The median number of positive biopsies was 2 (IQR 1) and the total number of positive biopsies was 27 (8%). The biopsy was positive at the initial tumor site in 8 patients (61.5%). No complications of Clavien III to V were reported. Out of 62 patients who underwent systematic transurethral biopsy, only 3 (5%) presented complications from grade I to II. We found a significant association of positive biopsy with positive urinary cytology (p <0.001) and the presence of erythematous lesions (p <0.02) or visible tumors (p <0.001) at cystoscopy. The pre-BCG stage T (p = 0.32), the presence of CIS (p = 0.71), the multifocal tumor (p = 0.41) and the size (p = 0.52) were not associated with a positive biopsy occurrence. For normal bladder mucosa the predictive value of negative biopsy in cases with negative vs positive cytology was 98% vs 79% (p 0.001). Conclusion: Routine transurethral bladder biopsies after a BCG induction course are not mandatory in the modern era of NMIBC management.