The role of light intensity, irradiation time and photoactive substance concentration in photodynamic therapy of tumors in preclinical research.

The role of physical parameters such as light intensity, irradiation time, light wave-length and photoactive substance concentration during photodynamic therapy is discussed. Optimal values for all these parameters were determined in a well defined biological model based on the treatment of CMC-2 fibrosarcoma implanted in the right hind leg of CBA/HZgr mice.