title: Very early indicators of response to systemic therapy in lymphoma patients based on alterations in water diffusivity--a preliminary experience in 20 patients undergoing whole-body diffusion-weighted imaging.
abstract: OBJECTIVE
  To assess feasibility of whole-body diffusion-weighted MRI (wbDWI) for very early evaluation of response to therapy in different lymphoma subtypes.
  
  
  METHODS
  20 patients (10 male, 10 female; mean age 50.7±16.1±17.2 years) underwent wbDWI (calculation of apparent diffusion coefficient [ADC] with b=0, 800s/mm(2)) at baseline and within a median of 7 days after therapy onset. Lymphoma manifestations were evaluated with respect to changes in ADC and size at follow-up with up to six of the largest lesions per patient undergoing quantification. An increase in ADC as well as a decrease in size at follow-up was classified as responder, whereas neither change in ADC nor in size (or progression) was considered non-responder. Results were confirmed at interim measurements (after 3-4 chemotherapy cycles) and 6 months after treatment.
  
  
  RESULTS
  90 lymphoma lesions were analyzed. 18 patients were classified as responders and 2 as non-responder at FU (mean, 1 week). DWI results accurately (100%) correlated with the subsequent interim course of all lesions. mean baseline ADC was 0.79±0.28×10(-3)s/mm(2). For responders mean follow-upADC increased by 64.6±56.5% (p<0.001) whereas lesions size decreased by mean 14.4±13.3% (p<0.001). In the non-responder, both values did not significantly change. In patients classified as responders six months after treatment, meanADC increase at FU was 70.3±57.8% (p<0.001) whereas mean size decrease vs. baseline was 15.8±13.6% as compared to non-responders (22.4±39.9%) and 5.4±0.9%, respectively.
  
  
  CONCLUSIONS
  wbDWI with ADC analysis represents a feasible diagnostic tool for very early response assessment in lymphoma patients enabling also prediction of long-term response.
authors: Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany. Electronic address: marius.horger@med.uni-tuebingen.de.
authors: M
authors: M
authors: Horger
authors: Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany. Electronic address: cora.claussen@web.de.
authors: C
authors: C
authors: Claussen
authors: Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany. Electronic address: ulrich.kramer@med.uni-tuebingen.de.
authors: U
authors: U
authors: Kramer
authors: Department of Diagnostic Radiology-Neuraradiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany. Electronic address: mfench@yahoo.com.
authors: M
authors: M
authors: Fenchel
authors: Siemens Medical Solutions AG, Erlangen, Karl-Schall-Straße 6, 91052 Erlangen, Germany. Electronic address: matthias.lichy@googlemail.com.
authors: M
authors: M
authors: Lichy
authors: Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany. Electronic address: sascha.kaufmann@med.uni-tuebingen.de.
authors: S
authors: S
authors: Kaufmann
mesh_terms: D000328:Adult; D000368:Aged; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008223:Lymphoma / Q000175:diagnosis* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D016896:Treatment Outcome; D051598:Whole Body Imaging / Q000379:methods*; D055815:Young Adult
keywords: DWI; Lymphoma; MRI; Response evaluation