title: Prediction of response to neoadjuvant chemotherapy in osteosarcoma using dual-phase (18)F-FDG PET/CT.
abstract: OBJECTIVE
  We evaluated the ability of dual-phase (18)F-FDG PET/CT to predict the histological response after neoadjuvant chemotherapy (NAC) in osteosarcoma.
  
  
  METHODS
  Thirty-one patients with osteosarcoma treated with NAC and surgery were prospectively enrolled. After injection of (18)F-FDG, both early (~60 min) and delayed (~150 min) PET were acquired before and after the completion of NAC. SUVmax, early/delayed SUVmax change (RImax), and early/delayed SUVmean change (RImean) of tumour were measured before (SUV1, RImax1, and RImean1) and after NAC (SUV2, RImax2, and RImean2). Then, we calculated the percentage changes between SUV1 and SUV2 (%SUV).
  
  
  RESULTS
  Twelve patients (39%) exhibited good histological response after NAC. SUVmax, RImax, and RImean significantly decreased after NAC. Before NAC, only RImean1 predicted good histological response with the optimal criterion of < 10%, sensitivity of 92%, specificity of 57%, and accuracy of 71%. After NAC, %SUV, SUV2, and RImax2 predicted histological response. By using combined criterion of %SUV and RImax2 or SUV2 and RImean1 or SUV2 and RImax2, accuracies were 81%, 77%, and 77%, respectively.
  
  
  CONCLUSIONS
  The histological response after NAC could be predicted by using RImean1 before the initiation of NAC in osteosarcoma. The combined use of SUV and RI values may provide a better prediction.
  
  
  CONCLUSIONS
  • Pretreatment dual-phase FDG-PET was useful to predict histological response in osteosarcoma. • A combination of early and delayed PET may increase the predictive value. • Early/delayed SUV change of tumours significantly decreased after neoadjuvant chemotherapy.
authors: Division of Nuclear Medicine, Department of Radiology, College of Medicine, The Catholic University of Korea, Seocho-gu Banpo-dong 505, Seoul, Republic of Korea, 137-040.
authors: Byung Hyun
authors: BH
authors: Byun
authors: Sung Hoon
authors: SH
authors: Kim
authors: Sang Moo
authors: SM
authors: Lim
authors: Ilhan
authors: I
authors: Lim
authors: Chang-Bae
authors: CB
authors: Kong
authors: Won Seok
authors: WS
authors: Song
authors: Wan Hyeong
authors: WH
authors: Cho
authors: Dae-Geun
authors: DG
authors: Jeon
authors: Soo-Yong
authors: SY
authors: Lee
authors: Jae-Soo
authors: JS
authors: Koh
authors: Soo Kyo
authors: SK
authors: Chung
mesh_terms: D000293:Adolescent; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy*; D017024:Chemotherapy, Adjuvant / Q000379:methods; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D064847:Multimodal Imaging / Q000379:methods; D020360:Neoadjuvant Therapy / Q000379:methods; D012516:Osteosarcoma / Q000000981:diagnostic imaging / Q000188:drug therapy*; D049268:Positron-Emission Tomography / Q000379:methods; D012372:ROC Curve; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18