Can positron emission tomography improve the quality of care for head-and-neck cancer patients?

Purpose: Fluoro-2-deoxy-d-glucose-positron emission tomography (FDG-PET) is a functional imaging modality that measures the relative uptake of (18)FDG with PET. The purpose of this review is to assess the potential contributi on of FDG-PET scans to the treatment of head-and-neck cancer patients. Methods and Materials: Data were assessed from the literature with attentio n to what additional information may be gained from the use of FDG-PET in f our clinical settings: (1) detection of occult metastatic disease in the ne ck, (2) detection of occult primaries in patients with neck metastases, (3) detection of synchronous primaries or metastatic disease in the chest, and (4) detection of residual/recurrent locoregional disease. Results: Although the data are somewhat conflicting, FDG-PET appears to add little additional value to the physical examination and conventional imagi ng studies (supplemented by biopsy when appropriate) for the detection of s ubclinical. nodal metastases, unknown primaries, or disease in the chest. H owever, FDG-PET scans are quite useful in differentiating residual/recurren t disease from treatment-induced normal tissue changes. A positive FDG-PET scan at 1 month after radiotherapy is highly indicative of the presence of residual disease, and a negative scan at 4 months after treatment is highly predictive of tumor eradication. Conclusions: Large-scale studies using newer generation equipment and more defined methods are needed to more rigorously assess the potential of FDG-P ET in the detection of subclinical primary or simultaneous secondary tumors and of nodal or systemic spread. Currently, however, FDG-PET can contribut e to the detection of residual/early recurrent tumors, leading to the timel y institution of salvage therapy or the prevention of unnecessary biopsies of irradiated tissues, which may aggravate injury. (C) 2001 Elsevier Scienc e Inc.