title: The Feasibility of 18F-FDG PET scans 1 month after completing radiotherapy of squamous cell carcinoma of the head and neck.
abstract: Our purpose was to prospectively evaluate the efficacy of PET with (18)F-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 (18)F-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. (18)F-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 (18)F-FDG PET to be 88%, the specificity to be 95%, and the overall diagnostic accuracy to be 94.9%.
  
  
  CONCLUSIONS
  Our results indicate that (18)F-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 (18)F-FDG PET to be performed to evaluate the response to radiotherapy.
authors.affiliation: Department of Otorhinolaryngology, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea.
authors.forename: Sang Yoon
authors.initials: SY
authors.lastname: Kim
authors.forename: Sang-wook
authors.initials: SW
authors.lastname: Lee
authors.forename: Soon Yuhl
authors.initials: SY
authors.lastname: Nam
authors.forename: Ki Chun
authors.initials: KC
authors.lastname: Im
authors.forename: Jae-Seung
authors.initials: JS
authors.lastname: Kim
authors.forename: Seung Joon
authors.initials: SJ
authors.lastname: Oh
authors.forename: Seung Do
authors.initials: SD
authors.lastname: Ahn
authors.forename: Seong Soo
authors.initials: SS
authors.lastname: Shin
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Choi
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18