title: High discordance rates between sub-areolar and peri-tumoural breast lymphoscintigraphy.
abstract: OBJECTIVE
  To test the hypothesis that sub-areolar (SA) lymphoscintigraphy (LSG) identifies the same sentinel node as peri-tumoural (PT) injections.
  
  
  BACKGROUND
  It is commonly believed that all LSG techniques will identify the same sentinel lymph nodes (SLN) draining the breast. Hybrid imaging technology (SPECT/CT) allows accurate identification of the exact location of SLNs. Using SPECT/CT SA and PT LSG techniques were compared.
  
  
  METHODS
  In a multi-centre trial 39 patients sequentially underwent LSG (SA followed by PT) separated by 2-7 days. Patients were referred by 4 surgeons to 3 LSG centres, with standardization of isotope (99mTc-antimony sulfide colloid), LSG and SPECT/CT evaluation techniques. LSG were evaluated for SLN concordance and degree of discordance in the axilla and internal mammary nodes (IMN).
  
  
  RESULTS
  39 eligible patients, median age 62 years, were recruited. Successful axillary SLN mapping for SA and PT injection techniques was 87% and 95% respectively. Successful internal mammary SLN mapping occurred with SA and PT LSG in 5% and 36% respectively. Discordance was identified in the IMN (39%) and axilla (21%), with an overall rate of discordance between SA and PT LSG of 56%.
  
  
  CONCLUSIONS
  There is a high level of discordance in the localization of SLN by these commonly used LSG injection techniques. This discordance has implications for accuracy of axillary and extra-axillary staging and could impact on patient outcome.
authors.affiliation: Discipline of Surgery, Sydney Medical School, University of Sydney, Sydney, Australia; The Mater Hospital, North Sydney, Australia; Royal North Shore Hospital, St Leonards, Australia; Sydney Adventist Hospital, Wahroonga, Australia. Electronic address: fnoushi@med.usyd.edu.au.
authors.forename: F
authors.initials: F
authors.lastname: Noushi
authors.forename: A J
authors.initials: AJ
authors.lastname: Spillane
authors.forename: R F
authors.initials: RF
authors.lastname: Uren
authors.forename: R
authors.initials: R
authors.lastname: Cooper
authors.forename: S
authors.initials: S
authors.lastname: Allwright
authors.forename: K L
authors.initials: KL
authors.lastname: Snook
authors.forename: D
authors.initials: D
authors.lastname: Gillet
authors.forename: A M
authors.initials: AM
authors.lastname: Pearce
authors.forename: V
authors.initials: V
authors.lastname: Gebski
mesh_terms: D000328:Adult; D000368:Aged; D001365:Axilla; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D061305:Lymphoscintigraphy; D008875:Middle Aged; D019275:Radiopharmaceuticals; D021701:Sentinel Lymph Node Biopsy; D013671:Technetium Tc 99m Sulfur Colloid; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D019275:Radiopharmaceuticals; D013671:Technetium Tc 99m Sulfur Colloid
keywords: Axilla; Breast cancer; Internal mammary; SPECT/CT lymphoscintigraphy; Sentinel lymph node