For both patients with new and recurrent disease, biopsies will be taken at up to six sites identified by the surgeon: in the tumor center, tumor edge, area surrounding the tumor (if safe), areas seen to fluoresce intraoperatively and an area with MR enhancement outside the tumor region (if this can be accomplished safely). Prior to collecting these biopsies readings will be taken at the biopsied location with the PpIX point probe by the surgeon. For each of the 6 biopsies, they will be divided into 3 parts and distributed for further analysis as follows: one portion will be sent to the pathologist for assessment of tumor percentage, one portion will be evaluated by the Division of Biophysics at the University of Toronto for PpIX concentration and the other for assessment of fluorescence.