Photodynamic diagnosis with 5-aminolevulinic acid in the treatment of secondary urethral tumors: First in vitro and in vivo results

Objectives: Photodynamic diagnosis (PDD) is able to detect dysplasia and tr ansitional cell cancer of the bladder. We report our first experiences usin g PDD in the urethra. Materials and Methods: Three patients with secondary transitional cell canc er of the urethra were treated by using PDD. 5-Aminolevulinic acid (ALA) wa s applied in a mixture with lubricant to achieve long enough contact with t he urothelium. Negative effects were tested in vitro on three bladder cell lines. Results: In vitro assays showed no enhanced negative effects on the viabili ty of bladder cells using the combination of ALA/lubricant and medium in co mparison to lubricant/medium alone. All patients showed markedly fluorescen t areas, which were resected. The treatment was well tolerated without side effects attributable to the photosensitizer containing lubricant. Conclusion: Lubricant with ALA forms a viscous solution, which can successf ully be used for PDD in the urethra. Thus marking tumors by fluorescence ma y improve transurethral resection and thus preserve the urethra. Copyright (C) 2001 S. Karger AG, Basel.