RT Journal Article SR Electronic T1 The Feasibility of 18F-FDG PET Scans 1 Month After Completing Radiotherapy of Squamous Cell Carcinoma of the Head and Neck JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 373 OP 378 VO 48 IS 3 A1 Sang Yoon Kim A1 Sang-wook Lee A1 Soon Yuhl Nam A1 Ki Chun Im A1 Jae-Seung Kim A1 Seung Joon Oh A1 Seung Do Ahn A1 Seong Soo Shin A1 Eun Kyung Choi A1 Jong Hoon Kim YR 2007 UL http://jnm.snmjournals.org/content/48/3/373.abstract AB Our purpose was to prospectively evaluate the efficacy of PET with 18F-FDG 1 mo after the completion of radiotherapy in patients with squamous cell carcinoma of the head and neck (SCCHN). Methods: Ninety-seven patients underwent 18F-FDG PET scans before and after radiotherapy for nondisseminated SCCHN. The first scans were obtained no more than 4 wk before the start of radiotherapy, and follow-up scans were obtained 1 mo after the completion of radiotherapy. 18F-FDG PET images were analyzed using standardized uptake values (SUVs). All patients were followed for at least 6 mo or until death. Results: The median SUVs of preradiotherapy primary sites and nodes were 6.5 (range, 2.3–23.0) and 5.6 (range, 1.2–16.8), respectively. The median SUVs of postradiotherapy primary sites and nodes were 1.8 (range, basal status value to 9.7) and 1.8 (range, basal status value to 8.6), respectively. Evaluation of the postradiotherapy status of tumors in these SCCHN patients showed the sensitivity of 18F-FDG PET to be 88%, the specificity to be 95%, and the overall diagnostic accuracy to be 94.9%. Conclusion: Our results indicate that 18F-FDG PET might be a valuable imaging method for evaluating the response to radiotherapy in patients with SCCHN. One month after the completion of radiotherapy is not too early for follow-up 18F-FDG PET to be performed to evaluate the response to radiotherapy.