title: Apparent diffusion coefficient maps integrated in whole-body MRI examination for the evaluation of tumor response to chemotherapy in patients with multiple myeloma.
abstract: OBJECTIVE
  To determine the diagnostic value of apparent diffusion coefficient (ADC) maps in the assessment of response to chemotherapy in patients with multiple myeloma (MM).
  
  
  METHODS
  Fourteen patients (seven women) with MM underwent whole-body magnetic resonance imaging (WB-MRI) study on a 1.5T scanner, before and after chemotherapy. DWI with background body signal suppression (DWIBS) sequences (b values: 0, 500, and 1000 mm(2)/sec) were qualitatively analyzed, along with T1 turbo spine echo and short tau inversion recovery T2-weighted images, to evaluate bone lesions. On ADC maps, regions of interest were manually drawn along contours of lesions. The ADC values percentage variation (ΔADC) before (MR1) and after (MR2) chemotherapy were calculated and compared between responders (11 of 14) and nonresponders (3 of 14). The percentage of plasma cells by the means of the bone marrow aspirate was evaluated as parameter for response to chemotherapy.
  
  
  RESULTS
  Twenty-four lesions, hyperintense on DWIBS as compared to normal bone marrow, were evaluated. In responder group, the mean ADC values were 0.63 ± 0.24 × 10(-3) mm(2)/s on MR1 and 1.04 ± 0.46 × 10(-3) mm(2)/s on MR2; partial or complete signal intensity decrease during follow-up on DWIBS was found along with a reduction of plasma cells infiltration in the bone marrow. The mean ADC values for nonresponders were 0.61 ± 0.05 × 10(-3) mm(2)/s on MR1 and 0.69 ± 0.09 × 10(-3) mm(2)/s on MR2. The mean variation of ΔADC in responders (Δ = 66%) was significantly different (P < .05) than in nonresponders (Δ = 15%).
  
  
  CONCLUSIONS
  WB-MRI with DWIBS sequences, by evaluating posttreatment changes of ADC values, might represent a complementary diagnostic tool in the assessment of response to chemotherapy in MM patients.
authors.affiliation: School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza, Italy; Department of Diagnostic Radiology, H. San Gerardo, Monza, Italy; Department of Health Sciences, Tecnomed Foundation, University of Milano-Bicocca, Monza, Italy. Electronic address: pa.bonaffini@gmail.com.
authors.forename: Pietro Andrea
authors.initials: PA
authors.lastname: Bonaffini
authors.affiliation: School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza, Italy; Department of Diagnostic Radiology, H. San Gerardo, Monza, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Ippolito
authors.affiliation: School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza, Italy; Department of Diagnostic Radiology, H. San Gerardo, Monza, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Casiraghi
authors.affiliation: School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza, Italy; Department of Diagnostic Radiology, H. San Gerardo, Monza, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Besostri
authors.affiliation: School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza, Italy; Department of Diagnostic Radiology, H. San Gerardo, Monza, Italy.
authors.forename: Cammillo Talei
authors.initials: CT
authors.lastname: Franzesi
authors.affiliation: School of Medicine, University of Milano-Bicocca, Via Pergolesi 33, 20900 Monza, Italy; Department of Diagnostic Radiology, H. San Gerardo, Monza, Italy.
authors.forename: Sandro
authors.initials: S
authors.lastname: Sironi
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001854:Bone Marrow Cells / Q000187:drug effects; D002452:Cell Count; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000000981:diagnostic imaging / Q000188:drug therapy*; D009367:Neoplasm Staging; D010950:Plasma Cells / Q000187:drug effects; D012074:Remission Induction; D051598:Whole Body Imaging / Q000379:methods*
keywords: ADC; Multiple myeloma; chemotherapy; whole-body MRI