title: Prediction of clinical outcome after stereotactic body radiotherapy for non-small cell lung cancer using diffusion-weighted MRI and (18)F-FDG PET.
abstract: OBJECTIVE
  To evaluate the use of diffusion-weighted magnetic resonance imaging (DW-MRI) and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for predicting disease progression (DP) among patients with non-small cell lung carcinoma (NSCLC) treated with stereotactic body radiotherapy (SBRT).
  
  
  METHODS
  Fifteen patients with histologically confirmed stage I NSCLC who underwent pre-treatment DW-MRI and PET and were treated with SBRT were enrolled. The mean apparent diffusion coefficient (ADC) value and maximum standardised uptake value (SUVmax) were measured at the target lesion and evaluated for correlations with DP.
  
  
  RESULTS
  The median pre-treatment ADC value was 1.04×10(-3) (range 0.83-1.29×10(-3))mm(2)/s, and the median pre-treatment SUVmax was 9.9 (range 1.6-30). There was no correlation between the ADC value and SUVmax. The group with the lower ADC value (≤1.05×10(-3)mm(2)/s) and that with a higher SUVmax (≥7.9) tended to have poor DP, but neither trend was statistically significant (p=0.09 and 0.32, respectively). The combination of the ADC value and SUVmax was a statistically significant predictor of DP (p=0.036).
  
  
  CONCLUSIONS
  A low ADC value on pre-treatment DW-MRI and a high SUVmax may be associated with poor DP in NSCLC patients treated with SBRT. Using both values in combination was a better predictor.
authors.affiliation: Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Iizuka
authors.affiliation: Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan. Electronic address: ymatsuo@kuhp.kyoto-u.ac.jp.
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Matsuo
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Umeoka
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nakamoto
authors.affiliation: Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Nami
authors.initials: N
authors.lastname: Ueki
authors.affiliation: Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Mizowaki
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
authors.affiliation: Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hiraoka
mesh_terms: D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000473:pathology / Q000532:radiotherapy*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D015588:Observer Variation; D049268:Positron-Emission Tomography / Q000379:methods; D019275:Radiopharmaceuticals; D016634:Radiosurgery / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Diffusion-weighted MRI; FDG-PET; Lung cancers; Stereotactic body radiotherapy