Fluorine-18-fluorodeoxyglucose - Positron emission tomography metabolic imaging in patients with lymphoma

Fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography (PET) provides unique information about the metabolic behavior of the malignant tumors, independent of morphological criteria. This technique is more sensitive in imaging lymphoma prior to therapy than conventional computed tomography (CT) imaging and Ga-67 scintigraphy. FDG-PET performed in patients with lymphoma offers important additional information on the presence of viable disease in residual masses of the tumor. It is also of great value in assessing therapy response in patients with Hodgkin's disease and non-Hodgkin's lymphoma, because of its ability to differentiate between fibrosis and active tumor. More studies are needed to assess the value of this method in long-term follow-up. In our institution this method is mostly used for clarification of residual post-therapy abnormalities that fall under the category of unconfirmed/uncertain complete remission. Our preliminary data on 14 patients indicate that this non-invasive, metabolic imaging is superior to CT and other conventional diagnostic methods in the post-therapy staging of lymphoma.