title: Marking axillary lymph nodes with radioactive iodine seeds for axillary staging after neoadjuvant systemic treatment in breast cancer patients: the MARI procedure.
abstract: OBJECTIVE
  The MARI procedure [marking the axillary lymph node with radioactive iodine (I) seeds] is a new minimal invasive method to assess the pathological response of nodal metastases after neoadjuvant systemic treatment (NST) in patients with breast cancer. This method allows axilla-conserving surgery in patients responding well to NST.
  
  
  METHODS
  Prior to NST, proven tumor-positive axillary lymph nodes were marked with a I seed. This marked lymph node is the so-called MARI-node. After NST, the MARI node was selectively removed using a γ-detection probe. A complementary axillary lymph node dissection was performed in all patients to assess whether pathological response in the MARI node was indicative for the pathological response in the additional lymph nodes.
  
  
  RESULTS
  A tumor-positive axillary lymph node was marked with a I seed in 100 patients. The MARI node was successfully identified in 97 of these 100 patients (identification rate 97%). Two patients did not undergo subsequent axillary lymph node dissection, leaving 95 patients for further analysis. The MARI node contained residual tumor cells in 65 of these 95 patients. In the other 30 patients, the MARI node was free of tumor, but additional positive lymph nodes were found in 5 patients. Thus, the MARI procedure correctly identified 65 of 70 patients with residual axillary tumor activity (false negative rate 5/70 = 7%).
  
  
  CONCLUSIONS
  This study shows that marking and selectively removing metastatic lymph nodes after neoadjuvant systemic treatment has a high identification rate and a low false negative rate. The tumor response in the marked lymph node may be used to tailor further axillary treatment after NST.
authors.affiliation: Departments of *Surgical Oncology †Pathology ‡Radiology §Medical Oncology; and ¶Statistics, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Mila
authors.initials: M
authors.lastname: Donker
authors.forename: Marieke E
authors.initials: ME
authors.lastname: Straver
authors.forename: Jelle
authors.initials: J
authors.lastname: Wesseling
authors.forename: Claudette E
authors.initials: CE
authors.lastname: Loo
authors.forename: Margaret
authors.initials: M
authors.lastname: Schot
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Drukker
authors.forename: Harm
authors.initials: H
authors.lastname: van Tinteren
authors.forename: Gabe S
authors.initials: GS
authors.lastname: Sonke
authors.forename: Emiel J Th
authors.initials: EJ
authors.lastname: Rutgers
authors.forename: Marie-Jeanne T F D
authors.initials: MJ
authors.lastname: Vrancken Peeters
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology / Q000601:surgery; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001365:Axilla; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D008207:Lymphatic Metastasis; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D016896:Treatment Outcome
chemical_list: D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals