Photodynamic diagnosis for follow-up of carcinoma in situ of the bladder

Renzo Colombo¹, Richard Naspro², Piera Bellinzoni², Fabio Fabbri², Giorgio Guazzoni², Vincenzo Scattoni¹, Andrea Losa², Patrizio Rigatti¹

¹Department of Urology, University Vita-Salute San Raffaele, Scientific Institute H. San Raffaele, Milan, Italy; ²Department of Urology, San Raffaele Turro, Milan, Italy

Introduction: A prospective study to evaluate the reliability of cystoscopy was performed with fluorescence (photodynamic diagnosis, PDD) compared with standard white light (WL) cystoscopy in patients with solitary carcinoma in situ (CIS), undergoing BCG treatment.

Materials and methods: Between February 2004 and March 2006, 49 patients suffering from CIS were enrolled in the study. Patients age was 68.5 ± 13.5 years (mean ± SD) and all presented CIS alone at inclusion. All suspicious areas were biopsied either under white light or blue light. Urine cytology was peformed on each patient before endoscopy.

Results: Out of 49 patients enrolled, 15 (30.6%) presented with positive urinary cytology. Out of 18 patients positive to CIS at biopsy, 14 (77.7%) could be diagnosed exclusively by means of PDD cystoscopy and transurethral bladder resection and 4 (22.3%) during both standard and PDD cystoscopy. No additional CIS could be diagnosed by standard WL cystoscopy alone. The overall false positive rate for PDD accounted for 33.3% compared with 7.1% for WL cytoscopy. A statistical correlation was documented between the number of CIS findings and PDD (r = 0.6976, p = 0.0002) while WL cystoscopy (r = 0.1870, p = 0.3816) and urinary cytology (r = 0.4965, p = 0.0136) correlated only weakly with CIS. The overall side effects related to the drugs were negligible overall.

Conclusions: These data show that PDD cystoscopy is more reliable than WL cytoscopy for the follow-up of CIS patients during BCG treatment. Long-term data and multicenter, prospective data are needed to assess the true impact on tumor recurrence and progression.

Keywords: bladder cancer, fluorescence, carcinoma in situ, endoscopy