title: The impact of histopathology on nodal metastases in minimal breast cancer.
abstract: OBJECTIVE
  To establish a model based on risk factor analysis to guide selective axillary lymph node dissection in patients with T1a and T1b breast cancers.
  
  
  METHODS
  Retrospective review to determine histopathologic features and patient demographic profiles that may influence the incidence of nodal metastases.
  
  
  METHODS
  Primary care and referral centers in Rhode Island and Massachusetts.
  
  
  METHODS
  Women with invasive breast cancers with nodal status reported to the statewide tumor registry, the Hospital Association of Rhode Island, and the tumor registry at Baystate Medical Center, Springfield, Mass, between January 1984 and December 1995. There were 12030 patients with breast cancer reported; 2185 (18%) of these had tumors 1 cm or less in diameter.
  
  
  METHODS
  None.
  
  
  METHODS
  Axillary node metastases.
  
  
  RESULTS
  The nodal status of 377 patients with T1a tumors and 1808 patients with T1b tumors was studied. Seventy-five percent had axillary dissections, and 16% were found to have nodal metastases. Thirty-one percent (29/93) of patients younger than 40 years had positive nodes compared with 15% (241/1546) of older patients (P = .001). The T1a tumors had fewer metastases than the T1b tumors did (11% vs 17%; P = .02). Nuclear grade was available in 49% of cases. Nuclear grades 2 and 3 were associated with nodal involvement twice as often as grade 1 tumors were (P = .002). Patients with no poor prognostic factors had a 7% or less chance of nodal involvement, while patients with all 3 poor prognostic indicators had a 33.5% chance of nodal involvement.
  
  
  CONCLUSIONS
  Selective nodal dissection may be possible through risk factor analysis. Prospective registration of complete histopathologic information will allow more comprehensive analysis and may further enhance the selective treatment of patients with minimally invasive breast cancer.
authors.affiliation: Division of Surgical Oncology, Brown University, Providence, RI, USA.
authors.forename: I A
authors.initials: IA
authors.lastname: Mustafa
authors.forename: B
authors.initials: B
authors.lastname: Cole
authors.forename: H J
authors.initials: HJ
authors.lastname: Wanebo
authors.forename: K I
authors.initials: KI
authors.lastname: Bland
authors.forename: H R
authors.initials: HR
authors.lastname: Chang
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors