title: Tumor biology correlates with rates of breast-conserving surgery and pathologic complete response after neoadjuvant chemotherapy for breast cancer: findings from the ACOSOG Z1071 (Alliance) Prospective Multicenter Clinical Trial.
abstract: OBJECTIVE
  To determine the impact of tumor biology on rates of breast-conserving surgery and pathologic complete response (pCR) after neoadjuvant chemotherapy.
  
  
  BACKGROUND
  The impact of tumor biology on the rate of breast-conserving surgery after neoadjuvant chemotherapy has not been well studied.
  
  
  METHODS
  We used data from ACOSOG Z1071, a prospective, multicenter study assessing sentinel lymph node surgery after neoadjuvant chemotherapy in patients presenting with node-positive breast cancer from 2009 through 2011, to determine rates of breast-conserving surgery and pCR after chemotherapy by approximated biologic subtype.
  
  
  RESULTS
  Of the 756 patients enrolled on Z1071, 694 had findings available from pathologic review of breast and axillary specimens from surgery after chemotherapy. Approximated subtype was triple-negative in 170 (24.5%), human epidermal growth factor receptor 2 (HER2)-positive in 207 (29.8%), and hormone-receptor-positive, HER2-negative in 317 (45.7%) patients. Patient age, clinical tumor and nodal stage at presentation did not differ across subtypes. Rates of breast-conserving surgery were significantly higher in patients with triple-negative (46.8%) and HER2-positive tumors (43.0%) than in those with hormone-receptor-positive, HER2-negative tumors (34.5%) (P = 0.019). Rates of pCR in both the breast and axilla were 38.2% in triple-negative, 45.4% in HER2-positive, and 11.4% in hormone-receptor-positive, HER2-negative disease (P < 0.0001). Rates of pCR in the breast only and the axilla only exhibited similar differences across tumor subtypes.
  
  
  CONCLUSIONS
  Patients with triple-negative and HER2-positive breast cancers have the highest rates of breast-conserving surgery and pCR after neoadjuvant chemotherapy. Patients with these subtypes are most likely to be candidates for less invasive surgical approaches after chemotherapy.
authors.affiliation: *Department of Surgery, Mayo Clinic, Rochester, MN †Alliance Statistics and Data Center, Duke University, Durham, NC ‡Alliance Statistics and Data Center, Mayo Clinic, Rochester, MN §Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston ¶Department of Surgery, Magee-Women's Hospital of University of Pittsburgh Medical Center, Pittsburgh, PA ‖Department of Surgery, University of Wisconsin-Madison, Madison **Department of Surgery, Columbia University Medical Center, NY ††Department of Surgery, University of Texas Southwestern Medical Center, Dallas; and ‡‡Department of Surgery, Carolinas Medical Center, Charlotte, NC.
authors.forename: Judy C
authors.initials: JC
authors.lastname: Boughey
authors.forename: Linda M
authors.initials: LM
authors.lastname: McCall
authors.forename: Karla V
authors.initials: KV
authors.lastname: Ballman
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Mittendorf
authors.forename: Gretchen M
authors.initials: GM
authors.lastname: Ahrendt
authors.forename: Lee G
authors.initials: LG
authors.lastname: Wilke
authors.forename: Bret
authors.initials: B
authors.lastname: Taback
authors.forename: A Marilyn
authors.initials: AM
authors.lastname: Leitch
authors.forename: Teresa
authors.initials: T
authors.lastname: Flippo-Morton
authors.forename: Kelly K
authors.initials: KK
authors.lastname: Hunt
mesh_terms: D001365:Axilla / Q000473:pathology; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery*; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D015412:Mastectomy, Segmental / Q000706:statistics & numerical data*; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011446:Prospective Studies; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human