title: Dynamic contrast-enhanced CT to assess metabolic response in patients with advanced non-small cell lung cancer and stable disease after chemotherapy or chemoradiotherapy.
abstract: OBJECTIVE
  To compare tumour enhancement patterns measured using dynamic contrast-enhanced (DCE)-CT with tumour metabolism measured using positron emission tomography (PET)-CT in patients with non-small cell lung cancer (NSCLC) and stable disease after chemotherapy or chemoradiotherapy.
  
  
  METHODS
  After treatment, 75 NSCLC tumours in 65 patients who had stable disease on DCE-CT according to Response Evaluation Criteria in Solid Tumour (RECIST) were evaluated using PET-CT. On DCE-CT, relative enhancement ratios (RER) of tumour at 30, 60, 90, 120 s and 5 min after injection of contrast material were measured. Metabolic responses of tumours were classified into two groups according to the maximum standardized uptake value (SUVmax) by PET-CT: complete metabolic response (CR) with an SUVmax of less than 2.5, and noncomplete metabolic response (NR) with an SUVmax of at least 2.5.
  
  
  RESULTS
  Using the optimal RER₆₀ cutoff value of 43.7 % to predict NR of tumour gave 95.7 % sensitivity, 64.2 % specificity, and 82.1 % positive and 95.0 % negative predictive values. After adjusting for tumour size, the odds ratio for NR in tumour with an RER60 of at least 43.7 % was 70.85 (95 % CI = 7.95-630.91; P < 0.05).
  
  
  CONCLUSIONS
  Even when disease was stable according to RECIST, DCE-CT predicted hypermetabolic status of residual tumour in patients with NSCLC after treatment.
  
  
  CONCLUSIONS
  • Dynamic contrast-enhanced CT (DCE-CT) can provide useful metabolic information about non-small cell lung cancer. • NSCLC lesions, even grossly stable after treatment, show various metabolic states. • DCE-CT enhancement patterns correlate with tumour metabolic status as shown by PET. • DCE-CT helps to assess hypermetabolic NSCLC as stable disease after treatment.
authors.affiliation: Department of Radiology and Research Institute of Radiological Science, Yonsei University Health System, Seoul 135-720, Republic of Korea.
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Hwang
authors.forename: Mi Ri
authors.initials: MR
authors.lastname: Yoo
authors.forename: Chul Hwan
authors.initials: CH
authors.lastname: Park
authors.forename: Tae Joo
authors.initials: TJ
authors.lastname: Jeon
authors.forename: Sang Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Tae Hoon
authors.initials: TH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000628:therapy; D059248:Chemoradiotherapy / Q000379:methods; D003287:Contrast Media / Q000494:pharmacology*; D004358:Drug Therapy / Q000379:methods; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000494:pharmacology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D049268:Positron-Emission Tomography / Q000379:methods; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D019788:Fluorodeoxyglucose F18