title: Prognostic Significance of a Complete Response on Breast MRI in Patients Who Received Neoadjuvant Chemotherapy According to the Molecular Subtype.
abstract: OBJECTIVE
  To evaluate the relationship between response categories assessed by magnetic resonance imaging (MRI) or pathology and survival outcomes, and to determine whether there are prognostic differences among molecular subtypes.
  
  
  METHODS
  We evaluated 174 patients with biopsy-confirmed invasive breast cancer who had undergone MRI before and after neoadjuvant chemotherapy, but before surgery. Pathology findings were classified as a pathologic complete response (pCR) or a non-pCR, and MRI findings were designated as a radiologic CR (rCR) or a non-rCR. We evaluated overall and subtype-specific associations between clinicopathological factors including the assessment categories and recurrence, using the Cox proportional hazards model.
  
  
  RESULTS
  There were 41 recurrences (9 locoregional and 32 distant recurrences). There were statistically significant differences in recurrence outcomes between patients who achieved a radiologic or a pCR and patients who did not achieve a radiologic or a pCR (recurrence hazard ratio, 11.02; p = 0.018 and recurrence hazard ratio, 3.93; p = 0.022, respectively). Kaplan-Meier curves for recurrence-free survival showed that triple-negative breast cancer was the only subtype that showed significantly better outcomes in patients who achieved a CR compared to patients who did not achieve a CR by both radiologic and pathologic assessments (p = 0.004 and 0.001, respectively). A multivariate analysis found that patients who achieved a rCR and a pCR did not display significantly different recurrence outcomes (recurrence hazard ratio, 2.02; p = 0.505 and recurrence hazard ratio, 1.12; p = 0.869, respectively).
  
  
  CONCLUSIONS
  Outcomes of patients who achieved a rCR were similar to those of patients who achieved a pCR. To evaluate survival difference according to molecular subtypes, a larger study is needed.
authors.affiliation: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea.
authors.forename: Eun Sook
authors.initials: ES
authors.lastname: Ko
authors.affiliation: Department of Radiology, Kangwon National University Hospital, Chuncheon 24289, Korea.
authors.forename: Heon
authors.initials: H
authors.lastname: Han
authors.affiliation: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea.
authors.forename: Boo-Kyung
authors.initials: BK
authors.lastname: Han
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam 13620, Korea.
authors.forename: Sun Mi
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Department of Preventive Medicine, Dong-A University School of Medicine, Busan 49201, Korea.
authors.forename: Rock Bum
authors.initials: RB
authors.lastname: Kim
authors.affiliation: Division of Oncology-Hematology, Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju 52727, Korea.
authors.forename: Gyeong-Won
authors.initials: GW
authors.lastname: Lee
authors.affiliation: Division of Hematology/Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea.
authors.forename: Yeon Hee
authors.initials: YH
authors.lastname: Park
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea.
authors.forename: Seok Jin
authors.initials: SJ
authors.lastname: Nam
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D016016:Proportional Hazards Models; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism; D011980:Receptors, Progesterone / Q000235:genetics / Q000378:metabolism; D012074:Remission Induction
chemical_list: D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone
keywords: Breast cancer; Magnetic resonance imaging; Neoadjuvant chemotherapy; Prognosis; Subtype