Trial Information

Co-registered Fluorescence-Enhanced Resection of Brain Tumors Stage I: Correlation With MR and Biopsy

The first phase of study (Stage I) will use FI coregistered with pMR, iUS and iSV images to
test the overall hypothesis that there is a high degree of spatial correlation between local
tissue FI signal and coregistered conventional imaging and corresponding histopathology.
Additionally, coregistered probe measurements and biopsy specimens will be acquired
intraoperatively. Biopsy specimens will be processed post-operatively (via fluorescence
microscopy and chemical spectrofluorimetry) to assess PpIX concentration which will allow
direct comparisons of FI signal strength with PpIX production (based on both in vivo probe
data and ex vivo histological quantification) as a function of histological grade. The
study protocol is outlined below. Because of the overall interest and importance of
relating this data to the existing body of literature and the excellent safety record of
oral administration of ALA reported in these trials [1, 33-36], we will use the same
dose/time schedule described in [1, 33]. The operative procedures will follow existing
practice at Dartmouth for image-guided resection of meningiomas, pituitary adenomas and
metastases with additional acquisition of FI and biopsy data at predefined time points that
are related to the expected volume of tumor tissue. In this first phase of the study,
resection decisions will not be made based on FI data alone. Should residual fluorescence
remain after the intended resection volume has been removed further excisions will require
biopsy confirmation in the OR. It is anticipated that 234 patients will be enrolled in Stage
I.