title: Higher locoregional recurrence rate for triple-negative breast cancer following neoadjuvant chemotherapy, surgery and radiotherapy.
abstract: BACKGROUND
  Breast cancer subtype, determined by expression of estrogen/progesterone receptor (ER/PR) and human epidermal growth factor receptor (HER)-2, is predictive for prognosis. The importance of subtype to locoregional recurrence (LRR) following neoadjuvant chemotherapy (NAC) is unknown, particularly after adjuvant radiotherapy (RT).
  
  
  METHODS
  We retrospectively identified 160-breast cancer patients registered at Columbia University Medical Center from 1999 to 2012 treated with NAC, surgery and adjuvant RT.
  
  
  RESULTS
  Patients were grouped by receptor status: hormone receptor positive (HR+) [(ER or PR+)/HER2-; n = 75], HER2+ (n = 46), or triple-negative (TNBC) [ER (-) PR (-) HER2 (-); n = 36]. The median follow-up was 28 months. 92.0% received an anthracycline-taxane based NAC and 80.4% of HER2+ patients received trastuzumab. All underwent surgical resection followed by RT. 15.6% had a pathologic complete response (pCR): 26% of HER2+, 5% of HR+, and 25% of TN. The actuarial rate of DM was 13.8% for the entire cohort, with equivalent rates by subtypes in non-pCR patients. The overall rate of LRR was 8%. However, the LRR rate was significantly higher for TNBC patients (22.2%) than HER2+ (5.6%) (p = 0.025) or HR+ (3.0%) (p = 0.037) in non-pCR group. In the pCR group, two patients had recurrence; one LRR and one a DM, both had TNBC. All LRR occurred in or near the radiation field.
  
  
  CONCLUSIONS
  TNBC patients with < pCR to NAC have a significantly higher LRR rate as compared to other subtypes even with surgery and adjuvant RT. Our data support a need to further intensify local therapy in TNBC patients.
authors.affiliation: Department of Radiation Oncology, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY USA.
authors.forename: Chi
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Biostatistics, Columbia University School of Medicine, New York, NY USA.
authors.forename: Shuang
authors.initials: S
authors.lastname: Wang
authors.affiliation: Columbia University School of Medicine, New York, NY USA.
authors.forename: Hayley P
authors.initials: HP
authors.lastname: Israel
authors.affiliation: Columbia University School of Medicine, New York, NY USA.
authors.forename: Sherry X
authors.initials: SX
authors.lastname: Yan
authors.affiliation: Department of Radiation Oncology, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY USA.
authors.forename: David P
authors.initials: DP
authors.lastname: Horowitz
authors.affiliation: Columbia University School of Medicine, New York, NY USA.
authors.forename: Seth
authors.initials: S
authors.lastname: Crockford
authors.affiliation: Department of Radiation Oncology, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY USA.
authors.forename: Daniela
authors.initials: D
authors.lastname: Gidea-Addeo
authors.affiliation: Department of Radiation Oncology, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY USA.
authors.forename: K S
authors.initials: KS
authors.lastname: Clifford Chao
authors.affiliation: Department of Medical Oncology, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Kalinsky
authors.affiliation: Department of Radiation Oncology, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY USA.
authors.forename: Eileen P
authors.initials: EP
authors.lastname: Connolly
keywords: Locoregional recurrence rate; Neoadjuvant chemotherapy; Radiation; Triple-negative breast cancer