title: Use of diffusion-weighted, intravoxel incoherent motion, and dynamic contrast-enhanced MR imaging in the assessment of response to radiotherapy of lytic bone metastases from breast cancer.
abstract: OBJECTIVE
  To investigate the value of diffusion-weighted (DW), perfusion-sensitive, and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) techniques in assessing the response of bone metastases from breast cancer to radiotherapy, with particular emphasis on the role of intravoxel incoherent motion (IVIM)-DW parameters as a potential valuable imaging marker of tumor response.
  
  
  METHODS
  Fifteen women having breast cancer and bone metastases underwent MRI before and after radiotherapy (3 weeks [time 1], 2 months [time 2], and 4 months [time 3]), consisting of DW, perfusion-sensitive (IVIM), and DCE acquisitions. MR-based DW and perfusion parameters, including water diffusivity (D), perfusion fraction (f), pseudodiffusion (D*), total apparent diffusion coefficient (ADC-total), fractionated ADCs (ADC-high and ADC-low), and initial area under the gadolinium concentration curve after the first 60 seconds (IAUGC60), were determined. The morphologic MRI findings were also recorded. A one-way repeated measures analysis of variance was used to compare the value of MR-based parameters at the different time points.
  
  
  RESULTS
  A significant variation between pretreatment (time 0) and post-treatment (times 1, 2, and 3) was found for ADC-total and D parameters (P < .001). A statistically significant reduction was also found for IAUGC60 values between times 0 and 3 (P < .001). A significant change across the different time points was observed for D* and IAUGC60 parameters (P < .001). On the contrary, there was no statistically significant change over time for parameters ADC-total, D, f, and IAUGC60 comparing response between each metastasis, that is, the response to therapy was similar for each metastasis.
  
  
  CONCLUSIONS
  DW, IVIM, and DCE-MRI techniques show effectiveness in assessing the response to radiotherapy in bone metastases from breast cancer.
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Gaeta
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy. Electronic address: cate.benedetto@gmail.com.
authors.forename: Caterina
authors.initials: C
authors.lastname: Benedetto
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Minutoli
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Tommaso
authors.initials: T
authors.lastname: D'Angelo
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Amato
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Silvio
authors.initials: S
authors.lastname: Mazziotti
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Santi
authors.initials: S
authors.lastname: Racchiusa
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Enricomaria
authors.initials: E
authors.lastname: Mormina
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Blandino
authors.affiliation: Section of Radiological Sciences, Department of Biomedical Sciences and Morphologic and Functional Imaging, University of Messina, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Pergolizzi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D016477:Artifacts; D001859:Bone Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000556:secondary*; D001943:Breast Neoplasms / Q000473:pathology* / Q000532:radiotherapy; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009038:Motion; D017063:Outcome Assessment, Health Care / Q000379:methods; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013669:Technetium Tc 99m Medronate; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D013669:Technetium Tc 99m Medronate
keywords: DCE-MRI; DW; IVIM; bone metastases; radiotherapy