title: Deep-inspiration breath-hold PET/CT of lung cancer: maximum standardized uptake value analysis of 108 patients.
abstract: Our aim was to compare the maximum standardized uptake value (SUVmax) between breath-hold (BH) PET/CT and free-breathing (FB) PET/CT.
  
  
  METHODS
  The features of phantom data were analyzed, after which a clinical study was performed. A total of 108 consecutive patients with lung cancer were examined using lutetium oxyorthosilicate (LSO)-based PET/CT. The patients were instructed to breathe freely during FB PET/CT. In BH PET/CT, the patients were instructed to hold their breath in the maximal inspiration position during the scout scan, for 10 s of the CT scan, and for as long as possible during the PET scan. BH time was recorded using a respiratory monitoring device. The %BH-index was defined as the percentage difference between SUVmax of FB PET and that of BH PET. Statistical analyses were performed using the following factors: %BH-index, age, body mass index, 18F-FDG dosage, blood glucose, BH time, lesion size, and location.
  
  
  RESULTS
  The highest %BH-index was 223.2. %BH-index in the lower lung area was significantly higher than that in the upper lung area (51.8 +/- 49.5 vs. 16.9 +/- 25.6, respectively). Lesion volume and maximum diameter in the high-%BH-index group were significantly lower than those in the low-%BH-index group, with the use of a %BH-index cutoff value of 37.l.
  
  
  CONCLUSIONS
  SUVmax of FB PET should not be taken as accurate, especially in the lower lung area and for small pulmonary lesions. BH PET/CT is expected to enable precise measurement of SUVmax and is thus recommended as part of the standard protocol for lung cancer.
authors.affiliation: Division of Nuclear Medicine, Kanagawa Cancer Center, Yokohama, Japan. kawanotsuyoshi@hotmail.com
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kawano
authors.forename: Eiji
authors.initials: E
authors.lastname: Ohtake
authors.forename: Tomio
authors.initials: T
authors.lastname: Inoue
mesh_terms: D000368:Aged; D016477:Artifacts; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D001239:Inhalation; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008187:Lutetium; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D017640:Silicates; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D017640:Silicates; C477682:lutetium orthosilicate; D019788:Fluorodeoxyglucose F18; D008187:Lutetium