Clinical Study to Assess the Safety and Efficacy of the SpectraCure P18 System

This trial tests a new light-based treatment (photodynamic therapy) called the SpectraCure P18 System for men with prostate cancer that has come back after radiation therapy, to assess whether it is safe and effective at destroying the recurring tumor without surgery. **You may be eligible if...** - You are a male over 18 (Phase 1) who has had prior radiation therapy for localized prostate cancer and your cancer has come back, confirmed by biopsy - Your prostate is small enough (under 50 cm³) and the cancer is confined to the prostate (not spread elsewhere) - You are not eligible for repeat surgery or additional radiation therapy - You are in good physical health (ECOG 0 or 1) with adequate blood counts, kidney, and liver function - Your expected survival is at least 8 months (Phase 1) or 12 months (Phase 2) **You may NOT be eligible if...** - Your cancer has spread beyond the prostate (advanced or metastatic disease) - You previously had seed implant brachytherapy - You have an active infection or a serious concurrent illness - You have a light-sensitivity disorder such as porphyria, or allergies to the study's light-activating drug (verteporfin) - You are receiving hormone therapy or another form of photosensitizing treatment - You have a history of severe radiation-related rectal injury Talk to your doctor to see if this trial is right for you.