[New functional imaging technique "positron emission tomography"].

A new functional imaging technique, positron emission tomography (PET) has been introduced to probe biochemical imaging in vivo using physiological tracers, such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18. This technique has been used for quantitative assessment of regional blood flow, metabolic rates, and various neurotransmission-receptor functions in the brain, myocardium, and various tumor tissues. Among them, F-18 fluorine labeled fluorodeoxyglucose (FDG) has been most widely used to assess exogenous glucose utilization. Recent experimental studies indicated that glucose metabolism is increased with enhanced glucose transporter gene in malignant tumors, PET with FDG has been used to assess tumor imaging. This technique has been shown to be useful for (1) early detection of malignant tumors, (2) differentiation of malignant from benign tumors, (3) staging of the tumor, (4) assessment of treatment effect, and (5) early detection of recurrence of tumors. In this review article, clinical values of PET in oncology has been introduced and summarized.