title: MRI evaluation of residual tumor size after neoadjuvant endocrine therapy vs. neoadjuvant chemotherapy.
abstract: OBJECTIVE
  To investigate if there is any difference in evaluation of residual tumor size after neoadjuvant chemotherapy (NAC) and neoadjuvant endocrine therapy (NAE).
  
  
  METHODS
  Seventy-eight tumors in 57 patients were prospectively enrolled. Residual tumor sizes in contrast-enhanced MRI after NAC and NAE were compared with those measured on surgical specimen by using linear regression analyses. The line slope values >1 indicates overestimation by MRI. Differences in types of shrinkage patterns: concentric shrinkage (CS) and dendritic shrinkage (DS) were also investigated.
  
  
  RESULTS
  Fifty lesions were treated with NAC and 28 lesions were treated with NAE. Shrinkage patterns were CS in 33 lesions and in 45 lesions. The slopes values were 0.75 (R=0.92) and 0.70 (R=0.90) for NAC and NAE, respectively, and no significant difference was observed (p=0.46). However, they were 1.02 (R=0.92) and 0.68 (R=0.92), respectively for CS and DS with significant difference (p<0.01). The difference between CS and DS was found only in a subgroup with size by MRI >20 mm.
  
  
  CONCLUSIONS
  Contrast enhanced MRI enabled fairly accurate measurement in NAE as well as in NAC.
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin Kawaharacho, Sakyoku, Kyoto 606-8507, Japan.
authors.forename: Kazuna
authors.initials: K
authors.lastname: Takeda
authors.forename: Shotaro
authors.initials: S
authors.lastname: Kanao
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Okada
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ueno
authors.forename: Masakazu
authors.initials: M
authors.lastname: Toi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishiguro
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Mikami
authors.forename: Shiro
authors.initials: S
authors.lastname: Tanaka
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D018365:Neoplasm, Residual; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D018931:Antineoplastic Agents, Hormonal