The Value of Transurethral Bladder Biopsy after Intravesical Bacillus Calmette-Guerin Instillation Therapy for Nonmuscle Invasive Bladder Cancer: A Retrospective, Single Center Study and Cumulative Analysis of the Literature

Purpose: We evaluated the need of routine transurethral biopsies after an induction course of intravesical bacillus Calmette-Guerin for high grade nonmuscle invasive bladder cancer. Materials and Methods: This retrospective study included 180 patients with high grade nonmuscle invasive bladder cancer who underwent a 6-week induction course of bacillus Calmette-Guerin. Cystoscopic findings, urinary cytology and pathological results of transurethral biopsy were evaluated. For cumulative meta-analysis we systematically reviewed studies indexed in MEDLINE (R), EMBASE (R) and Web of Science (R). The records of 740 patients from a total of 7 studies were finally analyzed. Results: Biopsy was positive in 58 patients (32%). Cystoscopy appeared normal in 75 patients (42%) and showed only erythema in 51 (28%) and tumor in 54 (30%), of whom 6 (8%), 11 (22%) and 41 (76%), respectively, showed positive findings at biopsy. The positive predictive value of erythema was 15% with negative cytology and 56% with positive cytology. The positive predictive value of a tumor with negative and positive cytology was 63% and 89%, respectively. A combination of negative cytology and normal cystoscopy was associated with a negative biopsy in 94% of cases. A total of 970 bladder biopsies were taken, of which 137 (14%) were positive, including 20 of 125 erythematous lesions (16%), 73 of 107 tumors (68%) and 44 of 738 normal-appearing areas (6%). Cumulative analysis findings were comparable. Conclusions: Routine transurethral bladder biopsies after a bacillus Calmette-Guerin induction course are not necessary. An individually approach is recommended, tailored from cystoscopic findings and cytology.