Onkológia 1/2006

THE PLACE AND CONTRIBUTION OF PET IN ONCOLOGICAL DIAGNOSTICS

Positron emission tomography (PET) is one of the tomographic methods of nuclear medicine known around the world for over 25 years. The clinical use was made possible only in last ten years thanks to the instalation of the cyclotrone type of accelerators for the production of positron tracers, the development of the radiopharmacy and availability of the imaging techniques using the detection of annihilation photons , which arise during interaction of positron with electron in the surrounding ambience.. The most important contribution is the diagnostic using of positron radiopharmaceuticals prepared from the biogene elements , 15O-oxygen, 11C-carbon, 13N-nitrogen anf 18ffluor (instead hydrogen). In the oncological diagnostics in present times is 18fDg (fluorodeoxyglucose) mostly used. By help of this radiopharmaceutical is possible on an unspecific principle to visualise the activity the activity (viability) of tumor proportionally to the glucose metabolism rate. This mode of metabolic visualisation is possible to use in differential diagnostic of viabile (active) tumor tissue, in the stating of the extent of the tumor diseases (staging), follow-up after oncological treatment and detect the place of reccurence of tumor, but also in the evalution of brain tumor grading and searching after primary tumor in the MUO (metastasis of unknown origine).

Keywords: PET, positron emission tomography, 18fDg, 18f-fluorodeoxyglucose, viability of tumors.