Improved diagnosis and therapy of superficial transitional cell carcinoma (TCC) of the urinary bladder by 5-aminolevulinic acid (5-ALA) induced protoporphyrin IX (PPIX) fluorescence: a prospective study in 100 patients

摘要

The prognosis of superficial bladder cancer is strongly related to a high recurrence rate and the presence of concomitant,, plane" tumor lesions uch as severe dysplasia or carcinoma in situ. They are frequently overlooked on white light cystoscopy. Furthermore, the traditional transurethral tumor resection of superficial bladder tumor is fredquently incomplete. This prospective study aimed to evaluate whether or not 5-ALA induced PPIX fluores-cence cystoscopy could increase the detection of superficial bladder tumors and/or ,, plane" carcinoma in situ invisible on white light cystoscopy. 100 patients with superficial TCC of the urinary bladder underwent cystoscopy under white light and under blue fluorescence light. 2 hours (1-4 hours) prior to cystoscopy 50 ml 3 per cent 5-ALA-solution were intravesically instilled into the empty bladder. All lesions visible on white light cystoscopy were compared with fluorescence findings and, vice versa, all fluorescence findings werde compared with white light cystoscopy findings. All lesions visible under white light, and all lesions only visible under 5-ALA induced fluorescence were resected/biopsied and histologically examined. A total 515 resections/biopsies was performed (5. 15 biopsies per patient). 297 tumors were detected, 257 of 297 (86.5 per cent) on white light, and 288 of 297 (96.7 per cent) on fluorescence cystoscopy. 9 of 297 tumors (3.0 per cent) were only detected by white light, but 31 of 297 tumors (10.4 per cent) were only detected by fluorescence cystoscopy, i.e. the mucosa was looking normal under white light but showed positive fluorescence; 7/77 (9.0 percent) pTaG1, 13/96 (13.5 per cent) pTaG2, 3/48 (6.3 per cent) pT1G2, 15/43 (34.9 per cent) pTaG3 or Cis and 2/23 (8.7 per cent) pT1G3 tumors. A total of 17 of 66 grade 3 superficial TCC would have been overlooked on white light cystoscopy, a finding of clinical importance. The sensitivity and specificity of white light cystos copy was 86.5 per cent and 45.4 per cent, respectively, wheras the sensitivity and specificity of fluorescence cystoscopy was 96.7 per cent and 26.6 per cent, respectively. No local or systemic side effects of intravesical instillation of 5-ALA solution was observed. In conclusion, ALA-induced fluorescence endoscopy proved to be a safe method to increase the tumor detection rate, especially the detection of carcinoma in situ and highly malignant pT1G3 tumors.