title: Pretreatment maximum standardized uptake value on 18F-fluorodeoxyglucose positron emission tomography is a predictor of outcome for stage I non-small cell lung cancer after stereotactic body radiotherapy.
abstract: OBJECTIVE
  Stereotactic body radiotherapy (SBRT) is commonly considered an important treatment option for patients with stage I non-small cell lung cancer (NSCLC) who have contraindications for surgery or refuse surgery. Many studies have reported that the maximum standardized uptake value (SUVmax) on 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) of the primary tumor has prognostic value for resected NSCLC. The purpose of this study was to determine whether SUVmax is a predictor of disease-free survival (DFS) in patients with stage I NSCLC after SBRT.
  
  
  METHODS
  In all patients, the diagnosis was pathologically or cytologically confirmed. The prescription dose was 48 Gy in four fractions at the isocenter. FDG-PET was performed before SBRT.
  
  
  RESULTS
  Twenty-nine patients were enrolled in this study. The median follow-up period was 14 months (range, 2-56 months). Regional lymph node metastasis and distant metastasis were observed in 5 (17%) and 2 (7%), respectively. The median SUVmax was 5.6 (range, 2.2-22.0). DFS at 2 years was significantly different between the low SUVmax (<8.0) and high SUVmax (≥8.0) groups (85 versus 17%). In univariate analysis, SUVmax and gross tumor volume were significantly correlated with DFS. Multivariate analysis included variables with P-values <0.20 and showed that only SUVmax was significantly correlated with DFS.
  
  
  CONCLUSIONS
  Pretreatment SUVmax on FDG-PET predicted the DFS in patients with stage I NSCLC after SBRT.
authors.affiliation: Department of Radiology, Gifu University Hospital, Gifu, Japan.
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Tanaka
authors.affiliation: Department of Radiology, Gifu University Hospital, Gifu, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Hayashi
authors.affiliation: Department of Radiology, Gifu University Hospital, Gifu, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Hoshi
mesh_terms: D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D016634:Radiosurgery / Q000379:methods
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: 18F-fluorodeoxyglucose; lung cancer; positron emission tomography; radiation therapy; stereotactic body radiotherapy