title: Assessment of the nature of residual masses at end of treatment in lymphoma patients using volume perfusion computed tomography.
abstract: OBJECTIVE
  To determine the diagnostic benefit of volume perfusion computed tomography (VPCT) at end of treatment for response assessment in lymphoma patients.
  
  
  METHODS
  Seventy-five patients with different lymphoma subtypes were included: 50/75 patients had residual masses at end of treatment, 26/50 patients underwent VPCT at baseline and at end of treatment, and 24/50 patients only had end-of-treatment VPCTs. We evaluated the size of the main lymphoma mass, its blood flow (BF), blood volume (BV) and k-trans, calculated ratios (baseline and end of treatment) as well as sensitivity/specificity/negative (NPV)/positive predictive values (PPV). For VPCT at end of treatment, a cutoff threshold between responders and non-responders was calculated.
  
  
  RESULTS
  For patients undergoing VPCT at baseline and end of treatment, reduction in size, BF, BV and k-trans was significant (P < 0.001). Identification of non-response was reached at: <53% reduction in size (sensitivity/specificity/accuracy/PPV/NPV of 88.89%/62.5%/80.77%/84.21%/71.43%), <15% reduction of BF (sensitivity/specificity/accuracy/PPV/NPV of 100%/37.5%/80.77%/0.26%/100%), or <45% reduction of k-trans (sensitivity/specificity/accuracy/PPV/NPV of 88.89%/75%/84.62%/88.89%/75%). In the subgroup undergoing VPCT at end of treatment, BF >18.51 ml/100 ml indicated non-responsiveness (sensitivity 92.86%, specificity 72.73%, accuracy 84%, PPV 81.25%, NPV 88.89%).
  
  
  CONCLUSIONS
  VPCT seems adequate for assessment of lymphoma response at end of treatment. The degree of residual lymphoma perfusion at end of treatment helps to identify patients likely to remain in remission 1 year after completion of therapy.
  
  
  CONCLUSIONS
  • Volume perfusion computed tomography (VPCT) offers measurements for assessing tumour response. • Perfusion parameter changes measured by VPCT correlate with antitumour therapy response. • In lymphoma, baseline and end-of-treatment perfusion parameter ratios can predict response. • Perfusion measurements after treatment identify patients likely to remain in remission.
authors.affiliation: Department of Diagnostic Radiology, Eberhard Karls University, Hoppe-Seyler-Str.3, 72076, Tübingen, Germany, roland.syha@gmx.net.
authors.forename: R
authors.initials: R
authors.lastname: Syha
authors.forename: L
authors.initials: L
authors.lastname: Grünwald
authors.forename: T
authors.initials: T
authors.lastname: Horger
authors.forename: D
authors.initials: D
authors.lastname: Spira
authors.forename: D
authors.initials: D
authors.lastname: Ketelsen
authors.forename: W
authors.initials: W
authors.lastname: Vogel
authors.forename: C D
authors.initials: CD
authors.lastname: Claussen
authors.forename: M
authors.initials: M
authors.lastname: Horger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001810:Blood Volume; D054893:Cone-Beam Computed Tomography; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D006801:Humans; D008223:Lymphoma / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D055420:Perfusion Imaging; D011446:Prospective Studies; D016879:Salvage Therapy / Q000379:methods; D012680:Sensitivity and Specificity