title: 18F-FDG-PET/CT Imaging as an early survival predictor in patients with primary high-grade soft tissue sarcomas undergoing neoadjuvant therapy.
abstract: OBJECTIVE
  Neoadjuvant therapy is associated with considerable toxicity and limited survival benefits in patients with soft tissue sarcoma (STS). We prospectively evaluated whether 2[18F]fluoro-2-deoxy-d-glucose ((18)F-FDG)-PET/computed tomographic (CT) imaging after the initial cycle of neoadjuvant therapy could predict overall survival in these patients.
  
  
  METHODS
  Thirty-nine patients underwent (18)F-FDG-PET/CT before and after one cycle of neoadjuvant therapy. Fifty-six patients underwent end-of-treatment PET. Overall survival was, among others, correlated with changes of SUV(peak) and histopathology.
  
  
  RESULTS
  One-, two-, and five-year survival rates were 95% ± 3.0%, 86% ± 4.6%, and 68% ± 6.6%, respectively. Median time to death was 30.9 months (mean, 27.7; range, 6.9-50.1). Optimal cutoff values for early and late decreases in SUV(peak) (26% and 57%, respectively) were significant predictors of survival in univariate survival analysis [P = 0.041; HR, 0.27; 95% confidence interval (CI), 0.08-0.95 and P = 0.045; HR, 0.31; 95% CI, 0.10-0.98]. Seven of 15 early PET nonresponders but only four of 24 early PET responders died during follow-up (P = 0.068). The only other significant survival predictor was surgical margin positivity (P = 0.041; HR, 3.31; 95% CI, 1.05-10.42). By multivariable analysis, early metabolic response (P = 0.016) and positivity of surgical margins (P = 0.036) remained significant survival predictors.
  
  
  CONCLUSIONS
  (18)F-FDG-PET predicted survival after the initial cycle of neoadjuvant chemotherapy in patients with STS and can potentially serve as an intermediate endpoint biomarker in clinical research and patient care.
authors.affiliation: Division of Surgical Oncology, University of California at Los Angeles, 10833 Le Conte Avenue, Rm 54-140 CHS, Los Angeles, CA 90095, USA.
authors.forename: Ken
authors.initials: K
authors.lastname: Herrmann
authors.forename: Matthias R
authors.initials: MR
authors.lastname: Benz
authors.forename: Johannes
authors.initials: J
authors.lastname: Czernin
authors.forename: Martin S
authors.initials: MS
authors.lastname: Allen-Auerbach
authors.forename: William D
authors.initials: WD
authors.lastname: Tap
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Dry
authors.forename: Tibor
authors.initials: T
authors.lastname: Schuster
authors.forename: Jeff J
authors.initials: JJ
authors.lastname: Eckardt
authors.forename: Michael E
authors.initials: ME
authors.lastname: Phelps
authors.forename: Wolfgang A
authors.initials: WA
authors.lastname: Weber
authors.forename: Fritz C
authors.initials: FC
authors.lastname: Eilber
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D015999:Multivariate Analysis; D020360:Neoadjuvant Therapy; D017063:Outcome Assessment, Health Care; D049268:Positron-Emission Tomography; D011379:Prognosis; D011446:Prospective Studies; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012509:Sarcoma / Q000000981:diagnostic imaging* / Q000188:drug therapy; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18