Prof. Lothar Lilge and Prof. Stehling have known each other since their days as physics students at Johann Goethe University in Frankfurt.

Prof. Lilge, one of the leading experts in the field of photodynamic therapy, Prof. of Biophysics at the University of Toronto and Senior Scientis at the Princess Margaret Cancer Center, Toronto, have this year established a collaboration in the field of PDT of prostate and bladder cancer at the VITUS Prostate Center in Offenbach.