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 Scientist at Princess Margaret Cancer Center, Toronto, have established a collaboration in the field of PDT of prostate and bladder cancer at VITUS Private Clinic this year.