Optical delivery and monitoring of photodynamic therapy of prostate cancer

Photodynamic therapy of recurrent prostate cancer is currently undergoing Phase II clinical trials with the vascular targeting drug TOOKAD. Proper PDT dosage requires sound estimates of the light fluence and drug concentration throughout the organ. The treatment requires multiple diffusing light delivery fibers placed in position according to a light dose treatment plan under ultrasound guidance. Fluence rate is monitored by multiple sensor fibers placed throughout the organ and in sensitive organs near the prostate. The combination of multiple light delivery and fluence sensor fibers is used to estimate the optical properties of the tissue and to provide a general fluence map throughout the organ. This fluence map is then used to estimate extent of photodynamic dose. Optical spectroscopy is used to monitor drug pharmacokinetics in the organ and blood hemodynamics within the organ. Further development of these delivery and monitoring techniques will permit full online monitoring of the treatment that will enable real-time patient-specific delivery of photodynamic therapy.