title: Impact of factors affecting the residual tumor size diagnosed by MRI following neoadjuvant chemotherapy in comparison to pathology.
abstract: OBJECTIVE
  To investigate accuracy of magnetic resonance imaging (MRI) for measuring residual tumor size in breast cancer patients receiving neoadjuvant chemotherapy (NAC).
  
  
  METHODS
  Ninety-eight patients were studied. Several MRI were performed during NAC for response monitoring, and the residual tumor size was measured on last MRI after completing NAC. Covariates, including age, tumor characteristics, biomarkers, NAC regimens, MRI scanners, and time from last MRI to operation, were analyzed. Univariate and Multivariate linear regression models were used to determine the predictive value of these covariates for MRI-pathology size discrepancy as the outcome measure.
  
  
  RESULTS
  The mean (±SD) of the absolute difference between MRI and pathological residual tumor size was 1.0 ± 2.0 cm (range, 0-14 cm). Univariate regression analysis showed tumor type, morphology, HR status, HER2 status, and MRI scanner (1.5 T or 3.0 T) were significantly associated with MRI-pathology size discrepancy (all P < 0.05). Multivariate regression analyses demonstrated that only tumor type, tumor morphology, and biomarker status considering both HR and HER-2 were independent predictors (P = 0.0014, 0.0032, and 0.0286, respectively).
  
  
  CONCLUSIONS
  The accuracy of MRI in evaluating residual tumor size depends on tumor type, morphology, and biomarker status. The information may be considered in surgical planning for NAC patients.
authors.affiliation: Tu & Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California; Department of Radiology, E-Da Hospital and I-Shou University, Kaohsiung, Taiwan.
authors.forename: Jeon-Hor
authors.initials: JH
authors.lastname: Chen
authors.forename: Shadfar
authors.initials: S
authors.lastname: Bahri
authors.forename: Rita S
authors.initials: RS
authors.lastname: Mehta
authors.forename: Philip M
authors.initials: PM
authors.lastname: Carpenter
authors.forename: Christine E
authors.initials: CE
authors.lastname: McLaren
authors.forename: Wen-Pin
authors.initials: WP
authors.lastname: Chen
authors.forename: Peter T
authors.initials: PT
authors.lastname: Fwu
authors.forename: David J B
authors.initials: DJ
authors.lastname: Hsiang
authors.forename: Karen T
authors.initials: KT
authors.lastname: Lane
authors.forename: John A
authors.initials: JA
authors.lastname: Butler
authors.forename: Min-Ying
authors.initials: MY
authors.lastname: Su
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D015999:Multivariate Analysis; D020360:Neoadjuvant Therapy; D018365:Neoplasm, Residual / Q000473:pathology*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012189:Retrospective Studies
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
keywords: MRI; biomarker; breast cancer; neoadjuvant chemotherapy; residual tumor size