title: Prognostic value of micrometastases in sentinel lymph nodes of patients with breast carcinoma: a cohort study.
abstract: BACKGROUND
  The prognostic meaning and thus indication for adjuvant therapy of lymphogenic micrometastases in breast cancer patients is still under debate.
  
  
  METHODS
  From 1999 to 2007, 703 patients with (c)T(1-2)N(0) breast cancer underwent surgery including sentinel lymph node biopsy. Examination of sentinel lymph nodes consisted of hematoxylin and eosin and immunohistochemistry staining following serial sectioning of the sentinel node. Patients were divided into four groups: (p)N(0) (n=423), (p)N(1micro) (n=81), (p)N(1a) (n=130) and (p)N(>or=1b) (n=69). Median follow-up was 40 months.
  
  
  RESULTS
  At the end of follow-up, 53 patients had died and 64 had recurrent disease. Compared with (p)N(0) and following adjustment for possible confounders, including adjuvant systemic treatment, overall survival was not significantly different for (p)N(1micro) while significantly worse for (p)N(1a) and (p)N(>or=1b) {hazard ratio (HR) [95% confidence interval (CI)]: 0.59 [0.14-2.58], 4.31 [1.85-10.01], 10.66 [4.04-28.14], respectively}. Likewise, disease-free survival was not significantly different for (p)N(1micro) and worse for (p)N(1a) and (p)N(>or=1b) (HR [95% CI]: 1.43 [0.67-3.02], 2.79 [1.37-5.66], 7.13 [3.27-15.54], respectively). Distant metastases were more commonly observed in the (p)N(1micro) than in the (p)N(0) group, but still not as common as in the (p)N(1a) or (p)N(>or=1b) group (HR [95% CI]: 4.85 [1.79-13.18], 10.34 [3.82-28.00], 23.25 [7.88-68.56], respectively).
  
  
  CONCLUSIONS
  Although the risk of distant metastases was higher in patients in the (p)N(1micro) than in the (p)N(0) group, no statistically significant differences were observed in overall or disease-free survival between (p)N(0) and (p)N(1micro). Micrometastatic lymph node involvement in itself should not be an indication for adjuvant chemotherapy in breast cancer patients.
authors.affiliation: Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands.
authors.forename: P D
authors.initials: PD
authors.lastname: Gobardhan
authors.forename: S G
authors.initials: SG
authors.lastname: Elias
authors.forename: E V E
authors.initials: EV
authors.lastname: Madsen
authors.forename: V
authors.initials: V
authors.lastname: Bongers
authors.forename: H J M
authors.initials: HJ
authors.lastname: Ruitenberg
authors.forename: C I
authors.initials: CI
authors.lastname: Perre
authors.forename: T
authors.initials: T
authors.lastname: van Dalen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D002277:Carcinoma / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D021701:Sentinel Lymph Node Biopsy; D016896:Treatment Outcome; D047368:Tumor Burden / Q000502:physiology; D055815:Young Adult
chemical_list: D018931:Antineoplastic Agents, Hormonal