Analysis and imaging: PET

Abstract

BNCT confers a tumoricidal effect that is heavily influenced not by the type of irradiation but by the biological distribution of boronated substrate injected into the body. Therefore, an important step in the planning for optimal BNCT for malignant tumor is to estimate the ratio of the boron concentration in tumor to surrounding normal tissue. One of the authors (KI) have first reported the radiosynthesis of the PET imaging probe [18F]FBPA and have confirmed its efficacy in estimating boron concentrations in animal experiments. A clinical PET application using [18F]FBPA have been started in clinical protocols in Japan for the selection of candidates for BNCT. Our comparative clinical imaging studies have revealed that [18F]FBPA PET images are almost identical to the images obtained with another amino acid probe, 11C methionine (MET). Static images of FBPA or MET-PET can be used for the planning of BNCT. PET imaging with amino acid probes may contribute significantly to the establishment of an appropriate BNCT application for patients with malignant tumors.