Discrepancies between cytology, cystoscopy and biopsy in bladder cancer detection after Bacille Calmette-Guerin intravesical therapy

Objectives:   To evaluate discrepancies in the detection of Bacille Calmette-Guerin (BCG)-resistant bladder cancer by cystoscopy, bladder biopsy and urinary cytology.
Methods:   Between January 1992 and August 2006, 127 bladder cancer patients underwent a cycle of eight weekly BCG instillations. Four weeks after the last BCG instillation, urinary cytological analysis and cystoscopy with targeted biopsy in addition to eight–nine selected-site biopsies were performed.
Results:   Biopsy-proven cancer was found in 11/27 (40.7%), 5/42 (11.9%), and 11/58 (19.0%) of positive, suspicious, and negative cytology cases, respectively. Abnormal and normal cystoscopic findings correlated with a biopsy-proven cancer in 13/53 (24.5%) and 14/74 (18.9%) cases, respectively. The combination of a macroscopic cystoscopic suspicion and a positive cytology missed malignant cases in 15.9% of the cases. In 100 cases without biopsy-proven cancer, the rates of denuded urothelium at biopsy in the cases with positive and non-positive cytology were 7/16 (43.8%) and 16/84 (19.0%), respectively
Conclusions:   According to our study, routine biopsy is recommended in the evaluation of BCG treatment, even if the timing, limitations and disadvantages of the procedure should be taken into account.