title: Comparison of integrated whole-body PET/MR and PET/CT: Is PET/MR alternative to PET/CT in routine clinical oncology?
abstract: OBJECTIVE
  To compare the diagnostic accuracy of whole-body PET/CT and integrated PET/MR in relation to the total scan time durations.
  
  
  METHODS
  One hundred and twenty-three (123) patients (40 males and 83 females; mean age 59.6 years; range 20-83 years) with confirmed primary cancer and clinical suspicion of metastatic disease underwent whole-body 18F-FDG-PET/CT and 18F-FDG-PET/MR. Data acquisition was done after intravenous administration of 110-301 MBq radioactivity of 18F-FDG, and PET/MR data were acquired after the PET/CT data acquisition. The mean uptake times for PET/CT and PET/MR acquisition were 68.0 ± 8.0 and 98.0 ± 14 min, respectively. Total scan time was 20.0 and 25.0 min for whole-body PET/CT and PET/MR imaging.
  
  
  RESULTS
  The reconstructed PET/CT and PET/MR data detected 333/355 (93.8 %) common lesions in 111/123 (90.2 %) patients. PET/CT and PET/MR alone detected 348/355 and 340/355 lesions, respectively. No significant (p = 0.08) difference was observed for the overall detection efficiency between the two techniques. On the other hand, a significant difference was observed between the two techniques for the detection of lung (p = 0.003) and cerebrospinal (p = 0.007) lesions. The 15 lesions identified by PET/CT only included 8 lung, 3 lymph nodes, 2 bone, and 1 each of peritoneal and adrenal gland lesions. On the other hand, 7 (6 brain metastatic lesions and 1 bone lesion) were identified by PET/MR only.
  
  
  CONCLUSIONS
  Integrated PET/MR is a feasible whole-body imaging modality and may score better than PET/CT for the detection of brain metastases. To further prove diagnostic utility, this technique requires further clinical validation.
authors.affiliation: Department of Radiology, Fukushima Medical University Hospital, 1, Hikarigaoka, Fukushima, Fukushima Prefecture, Japan. shirou@fmu.ac.jp.
authors.forename: Shirou
authors.initials: S
authors.lastname: Ishii
authors.affiliation: Department of Radiological Technology, Faculty of Health Sciences, Hokkaido University of Science, Sapporo, Hokkaido, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Shimao
authors.affiliation: Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan.
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Hara
authors.affiliation: Department of Radiology, Fukushima Medical University Hospital, 1, Hikarigaoka, Fukushima, Fukushima Prefecture, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Miyajima
authors.affiliation: Department of Radiology, Fukushima Medical University Hospital, 1, Hikarigaoka, Fukushima, Fukushima Prefecture, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Kikuchi
authors.affiliation: Department of Organ Regulatory Surgery, Fukushima Medical University, Fukushima, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Takawa
authors.affiliation: Department of Organ Regulatory Surgery, Fukushima Medical University, Fukushima, Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kumamoto
authors.affiliation: Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.affiliation: Department of Radiology, Fukushima Medical University Hospital, 1, Hikarigaoka, Fukushima, Fukushima Prefecture, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Shishido
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008495:Medical Oncology / Q000379:methods*; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D009369:Neoplasms / Q000000981:diagnostic imaging*; D000072078:Positron Emission Tomography Computed Tomography; D018511:Systems Integration; D051598:Whole Body Imaging; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Lesion detectability; Oncology; PET/CT; PET/MR; Whole-body