title: Outcomes of a population-based series of early breast cancer patients with micrometastases and isolated tumour cells in axillary lymph nodes.
abstract: BACKGROUND
  Axillary lymph node staging is traditionally important to provide prognostic information to guide further treatment. However, the relevance of isolated tumour cells (ITC) or micrometastases in axillary nodes and the need for adjuvant treatment remain uncertain.
  
  
  METHODS
  Data from 18 370 patients with pT1-2 breast cancer with pN0, pN0i+ or pN1mi were analysed. The primary end point was 5-year disease-free survival (locoregional recurrence, distant metastases or contralateral breast cancer).
  
  
  RESULTS
  Five-year disease-free survival was 89.9% [95% confidence interval 89.5% to 90.4%]; and did not differ significantly between groups. After adjusting for prognostic factors (including treatment), patients with ITC had a comparable risk (hazard ratio = 1.12) as patients with node-negative disease, while patients with micrometastases had a 38% higher risk of recurrence.
  
  
  CONCLUSIONS
  Patients with ITC and node-negative breast cancer appear to have similar prognosis, and those with micrometastases have a 38% higher risk of tumour recurrence. However, considering that disease-free survival is already high, we are reluctant to advise chemotherapy in all patients with ITC or micrometastases. In future, genomic tumour characteristics might predict the propensity of dissemination from the primary cancer better than the status of the axillary lymph nodes.
authors.affiliation: Department of Research, Comprehensive Cancer Centre The Netherlands, Utrecht.
authors.forename: M
authors.initials: M
authors.lastname: van der Heiden-van der Loo
authors.forename: M
authors.initials: M
authors.lastname: Schaapveld
authors.forename: V K Y
authors.initials: VK
authors.lastname: Ho
authors.forename: S
authors.initials: S
authors.lastname: Siesling
authors.forename: E J T
authors.initials: EJ
authors.lastname: Rutgers
authors.forename: P H M
authors.initials: PH
authors.lastname: Peeters
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000453:epidemiology / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000187:drug effects / Q000473:pathology*; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy* / Q000473:pathology; D009367:Neoplasm Staging; D016896:Treatment Outcome
keywords: adjuvant therapy; breast cancer; cancer recurrence; isolated tumour cells; micrometastases; sentinel node