The fluorine-18(18F) labeled compound is obtained by nucleophilic substitution of a tosylate-precursor with no-carrier-added 18F-fluoride in a specific activity of > 74 MBq / nmol. The administration of 370 MBq 18F-FAZA will therefore correspond to < 5 nmol compound and will not exert any pharmacologic or toxicologic effect. Similar radiopharmaceutical such as 18FMISO showed no side effects in their clinical use in human (22)