title: HER-2 positive breast cancer is associated with an increased risk of positive cavity margins after initial lumpectomy.
abstract: BACKGROUND
  The effect of breast cancer subtype on margin status after lumpectomy remains unclear. This study aims to determine whether approximated breast cancer subtype is associated with positive margins after lumpectomy, which could be used to determine if there is an increased risk of developing local recurrence (LR) following breast-conserving surgery.
  
  
  METHODS
  We studied 1,032 consecutive patients with invasive cancer who received lumpectomies and cavity margin (CM) assessments from January 2003 to November 2012. The following data were collected: patient age, cT stage, pT stage, grade, status of CM, lymph node status, menopausal status, ER, PR, HER-2, and Ki67, as well as the presence of extensive intraductal component (EIC) and lymphovascular invasion (LVI). A χ2 test was used to compare categorical baseline characteristics. Univariate and multivariate logistic regression analyses were performed to evaluate associations between pathologic features of CM status. Kaplan-Meier actuarial cumulative rates of LR (ipsilateral in-breast) were calculated.
  
  
  RESULTS
  A total of 7,884 pieces of marginal tissue were collected from 1,032 patients, and 209 patients had positive CMs. Of the patients tested, 52.3% had luminal A subtype, 14.9% were luminal B, 12.8% were luminal-HER-2, 8.1% were HER-2 enriched, and 11.8% were triple negative. Univariate analysis showed that EIC (P < 0.001), LVI (P = 0.026), pN stage (N1 vs. N0: P = 0.018; N3 vs. N0: P < 0.001), and luminal B (P = 0.001) and HER-2 (P < 0.001) subtypes were associated with positive CMs. Multivariable analysis indicated that only EIC (P < 0.001), pN stage (P = 0.003), and HER-2 subtype (P < 0.001) were significantly correlated with positive CMs. On multivariable analysis, HER-2 subtype was an independent prognostic factor in LR (P = 0.031).
  
  
  CONCLUSIONS
  The HER-2 subtype was the predictive factor most associated with positive CMs and an independent prognostic factor for LR. This result suggests that the increased risk of LR in HER-2 breast cancer is due to an increased microscopic invasive tumor burden, which is indicated by margin status after lumpectomy.
authors.forename: Haixia
authors.initials: H
authors.lastname: Jia
authors.forename: Weijuan
authors.initials: W
authors.lastname: Jia
authors.forename: Yaping
authors.initials: Y
authors.lastname: Yang
authors.forename: Shunrong
authors.initials: S
authors.lastname: Li
authors.forename: Huiyi
authors.initials: H
authors.lastname: Feng
authors.forename: Jieqiong
authors.initials: J
authors.lastname: Liu
authors.forename: Nanyan
authors.initials: N
authors.lastname: Rao
authors.forename: Liang
authors.initials: L
authors.lastname: Jin
authors.forename: Jiannan
authors.initials: J
authors.lastname: Wu
authors.forename: Ru
authors.initials: R
authors.lastname: Gu
authors.forename: Liling
authors.initials: L
authors.lastname: Zhu
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.forename: Heran
authors.initials: H
authors.lastname: Deng
authors.forename: Yunjie
authors.initials: Y
authors.lastname: Zeng
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Erwei
authors.initials: E
authors.lastname: Song
authors.affiliation: Department of Breast Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 Yanjiangxi Road, Guangzhou 510120, PR China. fengxisu@vip.163.com.
authors.forename: Fengxi
authors.initials: F
authors.lastname: Su
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology / Q000601:surgery*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D018275:Carcinoma, Lobular / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015412:Mastectomy, Segmental / Q000009:adverse effects*; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000378:metabolism; D009367:Neoplasm Staging; D018365:Neoplasm, Residual / Q000175:diagnosis* / Q000378:metabolism; D011183:Postoperative Complications / Q000209:etiology*; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012189:Retrospective Studies; D047368:Tumor Burden; D055815:Young Adult
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human