Positron emission tomography in non-Hodgkin's lymphoma (NHL): relationship between tracer uptake and pathological findings, including preliminary experience in the staging of low-grade NHL.

Advances in imaging techniques have allowed more precise staging and better evaluation of the effect of new treatment modalities. The limitations of conventional morphologic imaging techniques are well known. Positron emission tomography (PET) using fluorine-18-labeled fluorodeoxyglucose is now routinely used for initial staging and re-evaluation during or after treatment of Hodgkin's disease and aggressive non-Hodgkin's lymphoma (NHL), but not in low-grade NHL. In the first part of this review, the relationship between glucose metabolism as measured by PET, pathological findings including histological grade and proliferative activity, and prognosis are analyzed. In the second part, the potential role of PET in the staging and follow-up of low-grade NHL is discussed. Published data indicate that PET may contribute to the management of low-grade follicular NHL.