title: Added value of semi-quantitative breast-specific gamma imaging in the work-up of suspicious breast lesions compared to mammography, ultrasound and 3-T MRI.
abstract: OBJECTIVE
  To prospectively analyse the diagnostic value of semi-quantitative breast-specific gamma imaging (BSGI) in the work-up of suspicious breast lesions compared with that of mammography (MG), breast ultrasound and MRI of the breast.
  
  
  METHODS
  Within a 15-month period, 67 patients with 92 breast lesions rated as Category IV or V according to the breast imaging reporting and data system detected with MG and/or ultrasound were included into the study. After the injection of 740-1110 MBq of Technetium-99m ((99m)Tc) SestaMIBI intravenously, scintigrams were obtained in two projections comparable to MG. The BSGI was analysed visually and semi-quantitatively by calculating a relative uptake factor (X). With the exception of two patients with cardiac pacemakers, all patients underwent 3-T breast MRI. Biopsy results were obtained as the reference standard in all patients. Sensitivity, specificity, positive- and negative-predictive values, accuracy and area under the curve were calculated for each modality.
  
  
  RESULTS
  Among the 92 lesions, 67 (72.8%) were malignant. 60 of the 67 cancers of any size were detected by BSGI with an overall sensitivity of 90%, only exceeded by ultrasound with a sensitivity of 99%. The sensitivity of BSGI for lesions <1 cm declined significantly to 60%. Overall specificity of ultrasound was only 20%. Specificity, accuracy and positive-predictive value were the highest for BSGI (56%, 80% and 85%, respectively). X was significantly higher for malignant lesions (mean, 4.27) and differed significantly between ductal types (mean, 4.53) and the other histopathological entities (mean, 3.12).
  
  
  CONCLUSIONS
  Semi-quantitative BSGI with calculation of the relative uptake factor (X) can help to characterize breast lesions. BSGI negativity may obviate the need for biopsy of breast lesions >1 cm with low or intermediate prevalence for malignancy.
  
  
  CONCLUSIONS
  Compared with morphological imaging modalities, specificity, positive-predictive value for malignancy and accuracy were the highest for BSGI in our study. BSGI negativity may support the decision not to biopsy in selected lesions with a low or low-to-moderate pre-test probability for malignancy.
authors.affiliation: 1 Department of Radiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: T
authors.initials: T
authors.lastname: Meissnitzer
authors.affiliation: 2 Department of Sociology and Cultural Science, University of Salzburg, Salzburg, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Seymer
authors.affiliation: 3 Department of Nuclear Medicine, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: P
authors.initials: P
authors.lastname: Keinrath
authors.affiliation: 3 Department of Nuclear Medicine, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: J
authors.initials: J
authors.lastname: Holzmannhofer
authors.affiliation: 3 Department of Nuclear Medicine, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Pirich
authors.affiliation: 1 Department of Radiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Hergan
authors.affiliation: 1 Department of Radiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: M W
authors.initials: MW
authors.lastname: Meissnitzer
mesh_terms: D001941:Breast Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D061705:Image-Guided Biopsy; D008279:Magnetic Resonance Imaging; D008327:Mammography; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi; D016217:Ultrasonography, Mammary
chemical_list: D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi