title: Heterogeneity in intratumoral regions with rapid gadolinium washout correlates with estrogen receptor status and nodal metastasis.
abstract: OBJECTIVE
  To evaluate heterogeneity within tumor subregions or "habitats" via textural kinetic analysis on breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for the classification of two clinical prognostic features; 1) estrogen receptor (ER)-positive from ER-negative tumors, and 2) tumors with four or more viable lymph node metastases after neoadjuvant chemotherapy from tumors without nodal metastases.
  
  
  METHODS
  Two separate volumetric DCE-MRI datasets were obtained at 1.5T, comprised of bilateral axial dynamic 3D T1 -weighted fat suppressed gradient recalled echo-pulse sequences obtained before and after gadolinium-based contrast administration. Representative image slices of breast tumors from 38 and 34 patients were used for ER status and lymph node classification, respectively. Four tumor habitats were defined based on their kinetic contrast enhancement characteristics. The heterogeneity within each habitat was quantified using textural kinetic features, which were evaluated using two feature selectors and three classifiers.
  
  
  RESULTS
  Textural kinetic features from the habitat with rapid delayed washout yielded classification accuracies of 84.44% (area under the curve [AUC] 0.83) for ER and 88.89% (AUC 0.88) for lymph node status. The texture feature, information measure of correlation, most often chosen in cross-validations, measures heterogeneity and provides accuracy approximately the same as with the best feature set.
  
  
  CONCLUSIONS
  Heterogeneity within habitats with rapid washout is highly predictive of molecular tumor characteristics and clinical behavior.
authors.affiliation: Department of Computer Science and Engineering, University of South Florida, Tampa, Florida, USA.
authors.forename: Baishali
authors.initials: B
authors.lastname: Chaudhury
authors.affiliation: Department of Computer Science and Engineering, University of South Florida, Tampa, Florida, USA.
authors.forename: Mu
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Department of Computer Science and Engineering, University of South Florida, Tampa, Florida, USA.
authors.forename: Dmitry B
authors.initials: DB
authors.lastname: Goldgof
authors.affiliation: Department of Computer Science and Engineering, University of South Florida, Tampa, Florida, USA.
authors.forename: Lawrence O
authors.initials: LO
authors.lastname: Hall
authors.affiliation: Department of Radiology, H. Lee Moffitt Cancer and Research Institute, Tampa, Florida, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Gatenby
authors.affiliation: Department of Radiology, H. Lee Moffitt Cancer and Research Institute, Tampa, Florida, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Gillies
authors.affiliation: Department of Radiology, H. Lee Moffitt Cancer and Research Institute, Tampa, Florida, USA.
authors.forename: Bhavika K
authors.initials: BK
authors.lastname: Patel
authors.affiliation: Department of Radiology, H. Lee Moffitt Cancer and Research Institute, Tampa, Florida, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Weinfurtner
authors.affiliation: Department of Radiology, H. Lee Moffitt Cancer and Research Institute, Tampa, Florida, USA.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Drukteinis
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001940:Breast / Q000378:metabolism / Q000473:pathology; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D005682:Gadolinium; D006801:Humans; D007089:Image Enhancement; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D011960:Receptors, Estrogen / Q000378:metabolism*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D011960:Receptors, Estrogen; D005682:Gadolinium
keywords: axillary lymph node metastases; breast cancer; estrogen receptor; habitats; magnetic resonance imaging; textural kinetics