Abstract 4143: Photodynamic detection using 5-aminolevulinic acid (ALA) of prostate cancer cells in the urine obtained following prostate massage

Abstract

Abstract Objectives: We evaluated the feasibility of photodynamic diagnosis (PDD) using 5-aminolevulinic acid (ALA) for detecting of prostate cancer (PCa) cells in the urine obtained following prostate massage. Material and methods: Urine samples were collected from 97 men who had prostate massage (attentive digital rectal examination) before prostate needle biopsy. Urine sediments were exposed to 5-ALA (1mM) for 2 hours and cytospun onto glass slides. Protoporphyrin IX (PPIX), which is the metabolite of 5-ALA in the heme biosynthetic pathway, was observed using the fluorescent microscope (excitation filter 380-420 nm, emission filter 590 nm) as a positive signal of cancer cell. Any fluorescent signal in the samples was evaluated as positive. After histological diagnosis, the result of 5-ALA detection was compared with the histological diagnosis. Results: Prostate cancer cells were successfully visualized by the PPIX. Of the 65 cases with biopsy-proven prostate cancer, 45 were evaluated as positive by 5-ALA exposure (sensitivity: 75 %). Although 32 cases were diagnosed as no cancer with biopsy, 10 5-ALA positive cases were detected (specificity: 68 %). The positive predictive value of 5-ALA cancer detection was 83 %. Conclusions: We have successfully demonstrated that PPIX in urine sediments treated with 5-ALA could be detected in the PCa patients. Furthermore, the false positive patients could be diagnosed as PCa in the future re-biopsy. So this cancer detecting system appears to have the useful clinical application. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4143. doi:10.1158/1538-7445.AM2011-4143