Use of positron emission tomography to study tumors in vivo.

Positron emission tomography (PET) is a non-invasive imaging technique. The ability of PET to visualize biochemistry and physiology in vivo distinguishes this technique from other imaging modalities and renders it of particular interest for oncological studies. PET studies can often differentiate between normal and neoplastic tissue, as well as identify early signs of malignant degeneration through biochemical or physiological changes. Over the past several years, PET studies have been useful in the early diagnosis and the selection of treatment, as well as in following the progression or regression of malignant disease processes. Of particular significance, PET findings can be quantified by using mathematical modeling and computerized data analysis, which makes it possible to produce quantitative images of human pathophysiology in vivo.