title: Detection of extra-axillary lymph node involvement with FDG PET/CT in patients with stage II-III breast cancer.
abstract: OBJECTIVE
  The aim of this prospective study was to assess the incidence of extra-axillary lymph node involvement on baseline FDG PET/CT in patients with stage II-III breast cancer scheduled for neo-adjuvant chemotherapy.
  
  
  METHODS
  Patients with invasive breast cancer of >3 cm and/or proven axillary lymph node metastasis were included for before neo-adjuvant chemotherapy. Baseline ultrasound of the infra- and supraclavicular regions was performed with fine-needle biopsy as needed. Subsequently FDG PET/CT was performed. All visually FDG-positive nodes were regarded as metastatic based on the previously reported high specificity of the technique.
  
  
  RESULTS
  Sixty patients were included. In 17 patients (28%) extra-axillary lymph nodes were detected by FDG PET/CT, localised in an intra-mammary node (1 lymph node in 1 patient), mediastinal (2 lymph nodes in 2 patients), internal mammary chain (9 lymph nodes in 8 patients), intra- and interpectoral (6 lymph nodes in 4 patients), infraclavicular (5 lymph nodes in 4 patients) and in the contralateral axilla (3 lymph nodes in 2 patients). Ultrasound-guided cytology had detected extra-axillary lymph node involvement in seven of these patients, but was unable to detect extra-axillary nodes in the other 10 patients with positive extra-axillary lymph nodes on FDG PET/CT. Radiotherapy treatment was altered in 7 patients with extra-axillary involvement (12% of the total group).
  
  
  CONCLUSIONS
  FDG PET/CT detected extra-axillary lymph node involvement in almost one-third of the patients with stage II-III breast cancer, including regions not evaluable with ultrasound. FDG PET/CT may be useful as an additional imaging tool to assess extra-axillary lymph node metastasis, with an impact on the adjuvant radiotherapy management.
authors: Department of Nuclear Medicine, The Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
authors: Tjeerd S
authors: TS
authors: Aukema
authors: Marieke E
authors: ME
authors: Straver
authors: Marie-Jeanne T F D Vrancken
authors: MJ
authors: Peeters
authors: Nicola S
authors: NS
authors: Russell
authors: Kenneth G A
authors: KG
authors: Gilhuijs
authors: Wouter V
authors: WV
authors: Vogel
authors: Emiel J T
authors: EJ
authors: Rutgers
authors: Renato A Valdés
authors: RA
authors: Olmos
mesh_terms: D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging / Q000556:secondary* / Q000628:therapy; D018275:Carcinoma, Lobular / Q000000981:diagnostic imaging / Q000556:secondary* / Q000628:therapy; D017024:Chemotherapy, Adjuvant; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods; D011446:Prospective Studies; D019275:Radiopharmaceuticals
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18