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Updated: Oct 4, 2026
A Murine Orthotopic Bladder Tumor Model and Tumor Detection System
Published on: January 12, 2017
Quantification of 5-aminolevulinic acid induced fluorescence improves the specificity of bladder cancer detection
D Zaak1, D Frimberger, H Stepp
1Department of Urology and Laser Research Laboratory, Klinikum Grosshadern, Ludwig-Maximilians-University of Munich, Munich, Germany.
Purpose:
5-Aminolevulinic acid induced fluorescence endoscopy has outstanding sensitivity for detecting early stage bladder cancer. Nevertheless, a third of the lesions that show specific fluorescence are histologically benign. We decreased the false-positive rate of 5-aminolevulinic acid induced fluorescence endoscopy by incorporating protoporphyrin IX fluorescence quantification into the standard cystoscopy procedure.
Materials And Methods:
In 25 cases (53 biopsies) of a history of or suspicion for bladder cancer 5-aminolevulinic acid induced fluorescence endoscopy and fluorescence image quantification were performed. For fluorescence image quantification images obtained with a target integrating color charge-coupled device camera were digitized and stored in a personal computer. Red-to-blue ratios were calculated from fluorescence positive lesions and results were correlated with hematoxylin and eosin histology.
Results:
Malignant fluorescence positive lesions showed significantly stronger fluorescence intensity than fluorescing lesions with benign histology. A threshold was established that decreased the false-positive rate by 30% without affecting sensitivity.
Conclusions:
Fluorescence image quantification is a new endoscopic method for objectively selecting multicolor fluorescence bladder lesion images for biopsy. It has the potential of eliminating human error by different surgeons with variable experience in fluorescence endoscopy.
