Author(s): Zaak D, Martin Kriegmair
OBJECTIVES: The initial encouraging results using 5-aminolevulinic acid (5-ALA) induced fluorescence endoscopy (AFE) have promised a procedure with an outstanding sensitivity for the detection of early stage bladder cancer. Summarized here is our clinical experience and data comprising 1012 fluorescence endoscopies. METHODS: Two hours, 30 minutes before endoscopy, 1.5 g 5-ALA dissolved in 50 mL of 5.7% sodium monohydrogen phosphate was instilled in patients intravesically. Before AFE, all patients underwent white light endoscopy, and a bladder washing cytologic specimen was obtained. A special light source provided blue light (375 to 440 nm) for fluorescence excitation. Suspicious sites were identified by their red fluorescence contrasting against backscattered blue light when observed through the long pass filter (445 nm) integrated into the telescope eyepiece. RESULTS: Two thousand four hundred seventy-five specimens were obtained (2.4 biopsies per AFE). In 552 AFEs (54.5%), neoplastic urothelial lesions were detected, in 34.2% only because of their positive fluorescence; 38.7% of these additionally detected neoplastic foci had poorly differentiated histologic features. CONCLUSIONS: AFE has proved to be a clinically feasible procedure with an outstanding detection rate for flat, urothelial, high-risk lesions.