title: Time to enhancement derived from ultrafast breast MRI as a novel parameter to discriminate benign from malignant breast lesions.
abstract: OBJECTIVE
  To investigate time to enhancement (TTE) as novel dynamic parameter for lesion classification in breast magnetic resonance imaging (MRI).
  
  
  METHODS
  In this retrospective study, 157 women with 195 enhancing abnormalities (99 malignant and 96 benign) were included. All patients underwent a bi-temporal MRI protocol that included ultrafast time-resolved angiography with stochastic trajectory (TWIST) acquisitions (1.0×0.9×2.5mm, temporal resolution 4.32s), during the inflow of contrast agent. TTE derived from TWIST series and relative enhancement versus time curve type derived from volumetric interpolated breath-hold examination (VIBE) series were assessed and combined with basic morphological information to differentiate benign from malignant lesions. Receiver operating characteristic analysis and kappa statistics were applied.
  
  
  RESULTS
  TTE had a significantly better discriminative ability than curve type (p<0.001 and p=0.026 for reader 1 and 2, respectively). Including morphology, sensitivity of TWIST and VIBE assessment was equivalent (p=0.549 and p=0.344, respectively). Specificity and diagnostic accuracy were significantly higher for TWIST than for VIBE assessment (p<0.001). Inter-reader agreement in differentiating malignant from benign lesions was almost perfect for TWIST evaluation (κ=0.86) and substantial for conventional assessment (κ=0.75).
  
  
  CONCLUSIONS
  TTE derived from ultrafast TWIST acquisitions is a valuable parameter that allows robust differentiation between malignant and benign breast lesions with high accuracy.
authors.affiliation: Department of Radiology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: aroel.mus@radboudumc.nl.
authors.forename: Roel D
authors.initials: RD
authors.lastname: Mus
authors.affiliation: Department of Radiology, Scientific Institute "Casa Sollievo della Sofferenza" Hospital, Viale Cappuccini 1, 71013, San Giovanni Rotondo, Foggia, Italy; Department of Radiology, Radboud University Medical Center (internal address 766), Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: cristinaborelli@hotmail.it.
authors.forename: Cristina
authors.initials: C
authors.lastname: Borelli
authors.affiliation: Department of Pathology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: peter.bult@radboudumc.nl.
authors.forename: Peter
authors.initials: P
authors.lastname: Bult
authors.affiliation: Siemens Healthcare, Erlangen, Germany. Electronic address: elisabeth.weiland@siemens.com.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Weiland
authors.affiliation: Department of Radiology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: nico.karssemeijer@radboudumc.nl.
authors.forename: Nico
authors.initials: N
authors.lastname: Karssemeijer
authors.affiliation: Department of Radiology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: jelle.barentsz@radboudumc.nl.
authors.forename: Jelle O
authors.initials: JO
authors.lastname: Barentsz
authors.affiliation: Department of Radiology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: albert.gubernmerida@radboudumc.nl.
authors.forename: Albert
authors.initials: A
authors.lastname: Gubern-Mérida
authors.affiliation: Department of Radiology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: bram.platel@radboudumc.nl.
authors.forename: Bram
authors.initials: B
authors.lastname: Platel
authors.affiliation: Department of Radiology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525GA Nijmegen, The Netherlands. Electronic address: ritse.mann@radboudumc.nl.
authors.forename: Ritse M
authors.initials: RM
authors.lastname: Mann
mesh_terms: D001940:Breast / Q000473:pathology; D001943:Breast Neoplasms / Q000473:pathology*; D062485:Breath Holding; D018270:Carcinoma, Ductal, Breast / Q000473:pathology*; D003287:Contrast Media; D003937:Diagnosis, Differential; D055088:Early Detection of Cancer; D005260:Female; D018226:Fibroadenoma / Q000473:pathology*; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D015588:Observer Variation; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D003287:Contrast Media
keywords: Breast neoplasms; Contrast media; Differential diagnosis; Magnetic resonance imaging; Screening