title: Diffusion-weighted MRI compared to FDG PET/CT for assessment of early treatment response in lymphoma.
abstract: BACKGROUND
  18F fluoro-deoxyglucose (FDG) positron emission tomography / computed tomography (PET/CT) is a well-recognized diagnostic tool used for staging and monitoring of therapy response for lymphomas. During the past decade diffusion-weighted (DW) magnetic resonance imaging (MRI) is increasingly being included in the assessment of tumor response for various cancers.
  
  
  OBJECTIVE
  To compare the change in maximum standardized uptake value (ΔSUVmax) from FDG PET/CT with the change in apparent diffusion coefficient (ΔADC) from DW MRI after initiation of the first cycle of chemotherapy in patients with Hodgkin's lymphoma (HL) and in patients with diffuse large B-cell lymphoma (DLBCL).
  
  
  METHODS
  Twenty-seven consecutive patients with histologically proven lymphoma and lymphomatous lymph nodes (LLN) of the neck (19 with HL, 8 with DLBCL) underwent FDG PET/CT and MRI of the neck before and after initiation of the first cycle of chemotherapy. The mean time interval from initiation of chemotherapy to imaging was 19 days and 2 days for FDG PET/CT and MRI, respectively. For each patient ΔSUVmax, ΔADC, and change in volume of the same LLN were compared.
  
  
  RESULTS
  There was a significant mean decrease of SUVmax by 70%, but no significant change in ADC. There was no significant reduction in LLN volume.
  
  
  CONCLUSIONS
  There was no significant correlation between ΔSUVmax and ΔADC. Thus, our data do not support that FDG PET/CT can be replaced by early DW MRI for response evaluation in lymphoma patients.
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Norway University of Oslo, Norway.
authors.forename: Trond
authors.initials: T
authors.lastname: Hagtvedt
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Norway.
authors.forename: Therese
authors.initials: T
authors.lastname: Seierstad
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Norway.
authors.forename: Kjersti V
authors.initials: KV
authors.lastname: Lund
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Norway.
authors.forename: Ayca M
authors.initials: AM
authors.lastname: Løndalen
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Norway Department of Nuclear Medicine and PET-Centre, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Trond V
authors.initials: TV
authors.lastname: Bogsrud
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Norway University of Oslo, Norway.
authors.forename: Hans-Jørgen
authors.initials: HJ
authors.lastname: Smith
authors.affiliation: The Intervention Centre, Oslo University Hospital, Norway.
authors.forename: Oliver M
authors.initials: OM
authors.lastname: Geier
authors.affiliation: Department of Oncology, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Norway.
authors.forename: Harald
authors.initials: H
authors.lastname: Holte
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Norway trond.mogens.aalokken@rikshospitalet.no.
authors.forename: Trond Mogens
authors.initials: TM
authors.lastname: Aaløkken
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D001761:Bleomycin / Q000008:administration & dosage; D003606:Dacarbazine / Q000008:administration & dosage; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D004317:Doxorubicin / Q000008:administration & dosage; D042241:Early Diagnosis; D005260:Female; D019788:Fluorodeoxyglucose F18; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000188:drug therapy*; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome; D014747:Vinblastine / Q000008:administration & dosage; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D001761:Bleomycin; D014747:Vinblastine; D003606:Dacarbazine; D004317:Doxorubicin
keywords: DW MRI; FDG PET/CT; lymph nodes; lymphoma; neck