title: Predictive factors for metastatic involvement of nonsentinel nodes in patients with breast cancer.
abstract: BACKGROUND
  The potential morbidity of an axillary lymph node dissection in patients with breast cancer can be avoided in patients with a negative sentinel node (SN).
  
  
  OBJECTIVE
  It may be possible to identify a subset of patients with a positive SN and without metastases in the remaining axillary lymph nodes.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  Both primary and referral hospital care.
  
  
  METHODS
  Data were studied for 255 consecutive patients with stage T1 or T2 breast cancer who had a successful identification of the SN.
  
  
  METHODS
  In patients with a positive SN, histological examination of all non-SNs that were negative by routine examination was the same as that for SNs (multiple sectioning and immunohistochemical analysis).
  
  
  METHODS
  The incidence of non-SN metastases was correlated with the surface area and number of SN metastases and primary tumor characteristics. A micrometastasis was defined as less than 1 mm(2).
  
  
  RESULTS
  Of 255 patients, the SN appeared to be positive in 93 (36%). Subsequent axillary lymph node dissection revealed positive non-SNs in 46 patients (49%). Patients with a single positive SN and patients with metastases less than 1 mm(2) in the SN had significantly less non-SN involvement than patients with more than 1 positive SN (40% vs. 78%) and patients with macrometastases (27% vs. 49%).
  
  
  CONCLUSIONS
  The incidence of non-SN metastases seemed to be related to the number of positive SNs and the size of SN metastases. However, in the group of patients with a positive SN, it was not possible to identify a subset of patients without non-SN metastases.
authors.affiliation: Department of Surgical Oncology, Vrije Universiteit Medical Center, PO Box 7057, 1007 MB Amsterdam, the Netherlands.
authors.forename: F D
authors.initials: FD
authors.lastname: Rahusen
authors.forename: H
authors.initials: H
authors.lastname: Torrenga
authors.forename: P J
authors.initials: PJ
authors.lastname: van Diest
authors.forename: R
authors.initials: R
authors.lastname: Pijpers
authors.forename: E
authors.initials: E
authors.lastname: van der Wall
authors.forename: J
authors.initials: J
authors.lastname: Licht
authors.forename: S
authors.initials: S
authors.lastname: Meijer
mesh_terms: D001365:Axilla; D001943:Breast Neoplasms / Q000473:pathology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011237:Predictive Value of Tests; D021701:Sentinel Lymph Node Biopsy