title: Internal mammary lymph drainage and sentinel node biopsy in breast cancer - A study on 1008 patients.
abstract: BACKGROUND
  Nowadays, axillary sentinel node (SN) biopsy is a standard procedure in the staging of breast cancer. Although the internal mammary (IM) lymph node status is a major independent prognostic factor in breast cancer patients, sampling of IM sentinel nodes (IMSNs) is not performed routinely. The aim of this study was to determine the likelihood of finding IM lymph node metastases in case of IM hotspots on lymphoscintigraphy and evaluate the relevance of IMSN biopsy as a method to improve staging.
  
  
  METHODS
  Between April 1997 and May 2006, a total of 1008 consecutive patients with clinically node-negative operable primary breast cancer were enrolled in a prospective study on SN biopsy. Both axillary and IMSNs were sampled, based on lymphoscintigraphy, intraoperative gamma probe detection and blue dye mapping, using 10 mCi (370 MBq) (99m)Tc-nanocolloid injected peritumorally, and 0.5-1.0 ml Patent Blue V injected intradermally.
  
  
  RESULTS
  Lymphoscintigraphy showed axillary sentinel nodes in 98% (989/1008) and IMSNs in 20% of the patients (196/1008). Sampling the IM basin, as based on the results of lymphoscintigraphy, was successful in 71% of the patients (139/196) and revealed metastases in 22% (31/139). In 29% of the patients with positive IMSNs (9/31) no axillary metastases were found.
  
  
  CONCLUSIONS
  Evaluation of IMSNs improves nodal staging in breast cancer. Patients with IM hotspots on lymphoscintigraphy have a substantial risk (22%) of metastatic involvement of the IM chain. In addition, true IM node-negative patients can be spared the morbidity associated with adjuvant radiotherapy.
authors.affiliation: Department of Surgery, University Hospital Maastricht, The Netherlands. e.heuts@surgery.azm.nl
authors.forename: E M
authors.initials: EM
authors.lastname: Heuts
authors.forename: F W C
authors.initials: FW
authors.lastname: van der Ent
authors.forename: M F
authors.initials: MF
authors.lastname: von Meyenfeldt
authors.forename: A C
authors.initials: AC
authors.lastname: Voogd
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001365:Axilla; D044963:Biopsy, Fine-Needle; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging / Q000473:pathology*; D042361:Mammary Glands, Human / Q000000981:diagnostic imaging / Q000473:pathology*; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D011877:Radionuclide Imaging / Q000379:methods; D019275:Radiopharmaceuticals; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D013668:Technetium Tc 99m Aggregated Albumin
chemical_list: D019275:Radiopharmaceuticals; D013668:Technetium Tc 99m Aggregated Albumin; C083602:technetium Tc 99m nanocolloid