Eku Shimosegawa1,2, Kayako Isohashi3, Sadahiro Naka4, Genki Horitsugi4, Jun Hatazawa3. 1. Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Suita, Japan. eku@mi.med.osaka-u.ac.jp. 2. Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita, Japan. eku@mi.med.osaka-u.ac.jp. 3. Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita, Japan. 4. Osaka University Hospital, Suita, Japan.
Abstract
OBJECTIVES: In boron neutron capture therapy (BNCT) for cancer, the accurate estimation of 10B tissue concentrations, especially in neighboring normal organs, is important to avoid adverse effects. The 10B concentration in normal organs after loading with 10B, however, has not been established in humans. In this study, we performed 4-borono-2-[18F]-fluoro-phenylalanine (18FBPA) PET in healthy volunteers and estimated the chronological changes in the 10B concentrations of normal organs. METHODS: In 6 healthy volunteers, whole-body 18FBPA PET scans were repeated 7 times during 1 h, and the mean 18FBPA distributions of 13 organs were measured. Based on the 18FBPA PET data, we then estimated the changes in the 10B concentrations of the organs when the injection of a therapeutic dose of 10BPA-fructose complex (10BPA-fr; 30 g, 500 mg/kg body weight) was assumed. RESULTS: The maximum mean 18FBPA concentrations were reached at 2-6 min after injection in all the organs except the brain and urinary bladder. The mean 18FBPA concentration in normal brain plateaued at 24 min after injection. When the injection of a therapeutic dose of 10BPA-fr was assumed, the estimated mean 10B concentration in the kidney increased to 126.1 ± 24.2 ppm at 3 min after injection and then rapidly decreased to 30.9 ± 7.4 ppm at 53 min. The estimated mean 10B concentration in the bladder gradually increased and reached 383.6 ± 214.7 ppm at 51 min. The mean 10B concentration in the brain was estimated to be 7.6 ± 1.5 ppm at 57 min. CONCLUSIONS: 18FBPA PET has a potential to estimate 10B concentration of normal organs before neutron irradiation of BNCT when several assumptions are validated in the future studies.
OBJECTIVES: In boron neutron capture therapy (BNCT) for cancer, the accurate estimation of 10B tissue concentrations, especially in neighboring normal organs, is important to avoid adverse effects. The 10B concentration in normal organs after loading with 10B, however, has not been established in humans. In this study, we performed 4-borono-2-[18F]-fluoro-phenylalanine (18FBPA) PET in healthy volunteers and estimated the chronological changes in the 10B concentrations of normal organs. METHODS: In 6 healthy volunteers, whole-body 18FBPA PET scans were repeated 7 times during 1 h, and the mean 18FBPA distributions of 13 organs were measured. Based on the 18FBPA PET data, we then estimated the changes in the 10B concentrations of the organs when the injection of a therapeutic dose of 10BPA-fructose complex (10BPA-fr; 30 g, 500 mg/kg body weight) was assumed. RESULTS: The maximum mean 18FBPA concentrations were reached at 2-6 min after injection in all the organs except the brain and urinary bladder. The mean 18FBPA concentration in normal brain plateaued at 24 min after injection. When the injection of a therapeutic dose of 10BPA-fr was assumed, the estimated mean 10B concentration in the kidney increased to 126.1 ± 24.2 ppm at 3 min after injection and then rapidly decreased to 30.9 ± 7.4 ppm at 53 min. The estimated mean 10B concentration in the bladder gradually increased and reached 383.6 ± 214.7 ppm at 51 min. The mean 10B concentration in the brain was estimated to be 7.6 ± 1.5 ppm at 57 min. CONCLUSIONS:18FBPA PET has a potential to estimate 10B concentration of normal organs before neutron irradiation of BNCT when several assumptions are validated in the future studies.
Authors: Dominika Skwierawska; José Antonio López-Valverde; Marcin Balcerzyk; Antonio Leal Journal: Cancers (Basel) Date: 2022-06-10 Impact factor: 6.575