title: Ultrasound-guided sentinel node procedure for nonpalpable breast carcinoma.
abstract: OBJECTIVE
  Peritumoral and periareolar tracer injection techniques lead to different lymphatic drainage in sentinel lymph node biopsy procedures. In a prospective study, the visualization and identification rates of the ultrasound (US)-guided tracer injection technique for palpable and nonpalpable breast tumors were evaluated.
  
  
  METHODS
  In 1262 consecutive patients with cT₁₋₂N0 breast cancer, sentinel lymph node biopsy was performed following peritumoral tracer injection. In the case of nonpalpable breast lesions, Tc-99m nanocolloid injections were given using a 7.5 MHz US probe. In the case of ultrasonographically nonvisible microcalcifications, the US-guided injection technique was wire guided.
  
  
  RESULTS
  In 331 patients with nonpalpable breast lesions (26.2%), the lymphoscintigraphic visualization and surgical retrieval rates of axillary sentinel lymph nodes (SLNs) were 98.5 and 99.4%, respectively. For internal mammary (IM) SLNs, these rates were 21.1 and 17.8%, respectively. These rates were similar in patients with palpable and nonpalpable tumors. Axillary metastases were detected in 38.7% of the patients with palpable tumors versus 16.5% of those with nonpalpable tumors (P<0.001), whereas IM metastases were found in 4.8 and 3.0% of patients, respectively (P=0.165).
  
  
  CONCLUSIONS
  In nonpalpable breast lesions, the US-guided injection technique is an accurate technique for SLN identification and retrieval. The substantial rates of IM metastases in both palpable and nonpalpable lesions favor a peritumoral tracer injection technique.
authors: Department of Surgery, Amphia Hospital, Breda, The Netherlands. pgobardhan@amphia.nl
authors: Paul D
authors: PD
authors: Gobardhan
authors: Eva V E
authors: EV
authors: Madsen
authors: Thijs
authors: T
authors: van Dalen
authors: Cornelis I
authors: CI
authors: Perre
authors: Vivian
authors: V
authors: Bongers
mesh_terms: D000368:Aged; D001365:Axilla; D001940:Breast / Q000000981:diagnostic imaging*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D005260:Female; D006801:Humans; D015552:Injections, Intralesional; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D013668:Technetium Tc 99m Aggregated Albumin; D018084:Ultrasonography, Interventional; D016217:Ultrasonography, Mammary
chemical_list: D019275:Radiopharmaceuticals; D013668:Technetium Tc 99m Aggregated Albumin; C083602:technetium Tc 99m nanocolloid