title: Analysis of Risk of Recurrence by Subtype in ≤ 1-cm Breast Tumors.
abstract: BACKGROUND
  Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer with higher recurrence rates than other breast cancer subtypes. Increasing numbers of women are being diagnosed with early-stage breast cancer because of improvements in screening mammography. TNBC is known to be highly sensitive to chemotherapy; however, the benefit of adjuvant chemotherapy among women with ≤ 1-cm, lymph node-negative TNBC is unknown.
  
  
  METHODS
  We evaluated the recurrence rates and recurrence-free survival of 437 women diagnosed with stage T1a-T1bN0 breast cancer from 1997 to 2009 at 2 institutions, with a median follow-up time of 6.2 years. Furthermore, we examined the treatment regimens of these women and evaluated the association of adjuvant chemotherapy with recurrence-free survival.
  
  
  RESULTS
  Chemotherapy was administered more often to younger women and to women with high-grade, human epidermal growth factor receptor 2-positive or TNBC. Recurrence-free survival did not differ significantly between TNBC and estrogen receptor-positive breast cancer (hazard ratio [HR], 0.33; 95% confidence interval [CI], 0.10-1.04; P = .058). After appropriate adjustments, no significant differences were detected in recurrence-free survival between the women who had received chemotherapy and those who had not among the women with TNBC (P = .132) or within any of the breast cancer subtypes (HR, 0.6; 95% CI, 0.2-1.9; P = .392).
  
  
  CONCLUSIONS
  Prospective trials of this subcentimeter node-negative breast cancer population are warranted to guide adjuvant chemotherapy decisions.
authors.affiliation: Huntsman Cancer Institute, Salt Lake City, UT; George E. Whalen Veterans Affairs Hospital, Salt Lake City, UT; Vanderbilt-Ingram Cancer Center, Nashville, TN. Electronic address: sarah.colonna@hci.utah.edu.
authors.forename: Sarah V
authors.initials: SV
authors.lastname: Colonna
authors.affiliation: Wake Forest Comprehensive Cancer Center, Winston-Salem, NC.
authors.forename: Ashantice K
authors.initials: AK
authors.lastname: Higgins
authors.affiliation: Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN.
authors.forename: Joann
authors.initials: J
authors.lastname: Alvarez
authors.affiliation: Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN.
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Saville
authors.affiliation: Wake Forest Comprehensive Cancer Center, Winston-Salem, NC.
authors.forename: Julia
authors.initials: J
authors.lastname: Lawrence
authors.affiliation: Vanderbilt-Ingram Cancer Center, Nashville, TN.
authors.forename: Vandana G
authors.initials: VG
authors.lastname: Abramson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D016016:Proportional Hazards Models; D012307:Risk Factors; D064726:Triple Negative Breast Neoplasms / Q000188:drug therapy / Q000401:mortality* / Q000473:pathology*
keywords: Chemotherapy; HER2(+); Node negative; Small tumor; Triple negative