title: The yield of SPECT/CT for anatomical lymphatic mapping in patients with breast cancer.
abstract: OBJECTIVE
  The recently introduced hybrid single-photon emission computed tomography camera with integrated CT (SPECT/CT) fuses tomographic lymphoscintigrams with anatomical data from CT. The purpose of this study was to explore this sophisticated technique in lymphatic mapping in breast cancer patients.
  
  
  METHODS
  We studied 134 patients who underwent SPECT/CT immediately after late planar imaging when these images showed an unusual drainage pattern (85 patients), a pattern that was difficult to interpret (27 patients), or nonvisualization (22 patients).
  
  
  RESULTS
  Planar imaging suggested 271 sentinel nodes in 112 of the 134 patients (84%). SPECT/CT showed 269 of these same nodes and indicated that two sites of radioactivity were caused by skin contamination. SPECT/CT visualized 19 additional sentinel nodes in 15 patients, of whom 11 had non-visualization on planar images. One or more tumour-positive sentinel nodes were seen in 27 patients, and in 4 of these patients (15%), these were visualized only by SPECT/CT. SPECT/CT had no additional value for the surgical approach in 11 patients with persisting nonvisualization (8%), and was of questionable value in 67 other patients (50%). Based on the SPECT/CT images, a more precise incision was made in 48 patients (36%), an extra incision was made in 6 (4%), and an incision was omitted in 2 (1.5%).
  
  
  CONCLUSIONS
  SPECT/CT detected additional sentinel nodes and showed the exact anatomical location of sentinel nodes in breast cancer patients with inconclusive planar images. SPECT/CT was able to visualize drainage in patients whose planar images did not reveal a sentinel node. Therefore, SPECT/CT facilitates surgical exploration in difficult cases and may improve staging.
authors.affiliation: Department of Surgery, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands. i.vd.ploeg@nki.nl
authors.forename: Iris M C
authors.initials: IM
authors.lastname: van der Ploeg
authors.forename: Omgo E
authors.initials: OE
authors.lastname: Nieweg
authors.forename: Bin B R
authors.initials: BB
authors.lastname: Kroon
authors.forename: Emiel J T
authors.initials: EJ
authors.lastname: Rutgers
authors.forename: Marie-Jeanne T F D
authors.initials: MJ
authors.lastname: Baas-Vrancken Peeters
authors.forename: Wouter V
authors.initials: WV
authors.lastname: Vogel
authors.forename: Cornelis A
authors.initials: CA
authors.lastname: Hoefnagel
authors.forename: Renato A Valdés
authors.initials: RA
authors.lastname: Olmos
mesh_terms: D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008875:Middle Aged; D009367:Neoplasm Staging; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed