title: Axillary Ultrasound Accurately Excludes Clinically Significant Lymph Node Disease in Patients With Early Stage Breast Cancer.
abstract: OBJECTIVE
  Assess the performance characteristics of axillary ultrasound (AUS) for accurate exclusion of clinically significant axillary lymph node (ALN) disease.
  
  
  BACKGROUND
  Sentinel lymph node biopsy (SLNB) is currently the standard of care for staging the axilla in patients with clinical T1-T2, N0 breast cancer. AUS is a noninvasive alternative to SLNB for staging the axilla.
  
  
  METHODS
  Patients were identified using a prospectively maintained database. Sensitivity, specificity, and negative predictive value (NPV) were calculated by comparing AUS findings to pathology results. Multivariate analyses were performed to identify patient and/or tumor characteristics associated with false negative (FN) AUS. A blinded review of FN and matched true negative cases was performed by 2 independent medical oncologists to compare treatment recommendations and actual treatment received. Recurrence-free survival was described using Kaplan-Meier product limit methods.
  
  
  RESULTS
  A total of 647 patients with clinical T1-T2, N0 breast cancer underwent AUS between January 2008 and March 2013. AUS had a sensitivity of 70%, NPV of 84%, and PPV of 56% for the detection of ALN disease. For detection of clinically significant disease (>2.0 mm), AUS had a sensitivity of 76% and NPV of 89%. FN AUS did not significantly impact adjuvant medical decision making. Patients with FN AUS had recurrence-free survival equivalent to patients with pathologic N0 disease.
  
  
  CONCLUSIONS
  AUS accurately excludes clinically significant ALN disease in patients with clinical T1-T2, N0 breast cancer. AUS may be an alternative to SLNB in these patients, where axillary surgery is no longer considered therapeutic, and predictors of tumor biology are increasingly used to make adjuvant therapy decisions.
authors.affiliation: *Department of Surgery†Department of Internal Medicine‡Division of Biostatistics§Department of Pathology, Washington University School of Medicine, St. Louis, MO.
authors.forename: Natalia S
authors.initials: NS
authors.lastname: Tucker
authors.forename: Amy E
authors.initials: AE
authors.lastname: Cyr
authors.forename: Foluso O
authors.initials: FO
authors.lastname: Ademuyiwa
authors.forename: Adel
authors.initials: A
authors.lastname: Tabchy
authors.forename: Krystl
authors.initials: K
authors.lastname: George
authors.forename: Piyush K
authors.initials: PK
authors.lastname: Sharma
authors.forename: Linda X
authors.initials: LX
authors.lastname: Jin
authors.forename: Souzan
authors.initials: S
authors.lastname: Sanati
authors.forename: Rebecca
authors.initials: R
authors.lastname: Aft
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.forename: Julie A
authors.initials: JA
authors.lastname: Margenthaler
authors.forename: William E
authors.initials: WE
authors.lastname: Gillanders
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001365:Axilla / Q000000981:diagnostic imaging*; D001943:Breast Neoplasms / Q000473:pathology* / Q000628:therapy; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy; D015996:Survival Rate; D014463:Ultrasonography / Q000379:methods*