ABSTRACT
OBJECTIVES: To assess the ability of ultraviolet laser-induced autofluorescence for the diagnosis of transitional cell carcinoma of the bladder. METHODS: We studied 43 patients undergoing transurethral resection with recurrent transitional cell carcinoma of the bladder. Guided through 5-aminolevulinic acid-induced fluorescence endoscopy, the autofluorescence of the red fluorescing areas and the adjacent tissue and inconspicuous-appearing mucosa were measured spectroscopically. The autofluorescence excitation was carried out with a xenon chloride excimer laser operating at 308 nm (AF308). For the evaluation of the autofluorescence spectra, an intensity ratio (335/430 nm) was calculated and correlated with the histologic results of the biopsies taken. RESULTS: We analyzed the AF308 spectra of 114 biopsies (21 malignant, 93 benign). The autofluorescence intensity ratios for the benign lesions were a factor of 2 to 7 higher than carcinoma in situ and neoplastic tissue. Therefore, 20 of 21 neoplastic lesions were detected as true positive by AF308. A sensitivity and specificity for AF308 of 95% and 77%, respectively, could be calculated. The sensitivity and specificity for 5-aminolevulinic acid-induced fluorescence endoscopy was 90% and 61%, respectively. By combining the two methods, we calculated a sensitivity of 90% and a specificity of 84%. CONCLUSIONS: The combination of a sensitive imaging technique such as 5-aminolevulinic acid-induced fluorescence endoscopy and a more specific spectral fluorescence probe technique with autofluorescence at 308 nm is a very efficient procedure in the detection of transitional cell carcinoma of the bladder.
