ABSTRACT
OBJECTIVE: This study evaluates the utility of fluorodeoxyglucose-positron emission tomography (FDG-PET) in patients with head and neck squamous cell carcinoma (HNSCC) who received concurrent chemoradiotherapy (CCRT). METHODS: Sixty-five patients were recruited for this study between November 2002 and April 2007. The FDG-PET scan was performed before treatment and 4-6 weeks after treatment. RESULTS: The mean of maximum standardized uptake value (SUVmax) before treatment at the primary tumor site was 8.1 (range, 2-22). The sensitivity of FDG-PET for the diagnosis of primary tumor site was 98%. The mean of SUVmax after treatment was 2.6 (range, 2-5). The sensitivity, specificity, and accuracy of FDG-PET for the diagnosis of primary tumor site after treatment were 100%, 40%, and 46%, respectively. The mean of SUVmax before treatment at the nodal site was 4.7 (range, 2-16). The mean of SUVmax after treatment was 2.0 (range, 2-6.7). The pre-treatment SUVmax of T2, T3, and T4 stages were significantly higher than that of the T1 stage. The N stage had no correlation in terms of the pre-treatment nodal site SUVmax. CONCLUSION: Our results indicate that FDG-PET is a useful imaging method for evaluating the response of CCRT in patients with HNSCC. However, performing FDG-PET 4-6 weeks after treatment may be too early as it may give false-positive results due to fibrosis and scarring.
