ABSTRACT
Introduction 790 Positron emission tomography using 18F-FDG 790 Fluorodeoxyglucose imaging of lymphoma patients 791 18F-FDG PET versus other imaging tests (staging 791
and restaging) Evaluation of residual masses post-therapy 792 Extranodal lymphoma detection 792 Changes in patient management 793 Monitoring treatment response 793 Proliferation indices and grade of lymphomas 795 Summary 795 Gallium scintigraphy for detection of 795
malignant lymphomas Gallium as an iron analog 796
Transferrin receptors as 67Ga transporters 796 The use of gallium positron-emitting radionuclides 797
in lymphoma patient PET Bone scintigraphy 797 Radiolabeled antibodies for targeting lymphoma 798 Target antigens 798 Radiolabeling 798 Human applications of radiolabeled MAbs 799 99mTc-sestamibi scintigraphy applicable to lymphoma 799
localizations Evaluation of myocardial function during and 799
after chemotherapy Key points 801 References 801
The nuclear medicine tests available for staging and posttreatment evaluation of lymphoma patients are generally most useful when they are used to survey the patient for unsuspected sites of disease and/or to evaluate a physiologic or biochemical parameter to determine whether a suspected site or lesion found by an anatomic structural imaging test, such as computed tomography (CT) or magnetic resonance imaging (MRI), represents viable tumor tissue. Nuclear medicine tests are notable for relatively high sensitivity in detecting active disease but these tests often have low specificities. The multiplicity of possible disease locations in lymphomas and the wide variety of clinical presentations preclude a simple scheme for using nuclear medicine tests in the evaluation of each and every patient. We will thus discuss briefly some of the nuclear medicine tests available, their likely application, and give an indication of effectiveness. We shall begin with the most widely used of these, 2-[18F] fluoro-2-deoxyglucose (18F-FDG) positron emission tomography (PET), which has widespread application in lymphoma patient evalua-
An expanding area of oncology imaging is the use of PET with short-lived radiopharmaceuticals for physiological imaging of most tumors including lymphomas. The advantage of PET derives from the nature of positron tomography, which allows for more precise quantification of radioactivity in tumors. In addition to positron-emitting isotopes of gallium, there are a number of metabolicanalogue radiopharmaceuticals such as 18F-FDG which have shown potential as agents to permit improved PET imaging of lymphomas. Recent papers have even stated that in patients with untreated lymphomas (Hodgkin and various grade NHL) the degree to which their tumors accumulated 18F-FDG is correlated with the host patient’s prognosis.
