Katja Pinker MD, Presenter: Nothing to Disclose

Hubert Bickel MD, Abstract Co-Author: Nothing to Disclose

Benedikt Brück, Abstract Co-Author: Nothing to Disclose

Heinrich Magometschnigg, Abstract Co-Author: Nothing to Disclose

Stephan Gruber MD, Abstract Co-Author: Nothing to Disclose

Wolfgang Bogner MSC, Abstract Co-Author: Nothing to Disclose

Thomas Hans Helbich MD, Abstract Co-Author: Research Consultant, Siemens AG Research Consultant, Hologic, Inc Research Grant, Siemens AG

To demonstrate the feasibility of assessment of breast tumors with proton MR spectroscopy (3D-1H-MRSI), diffusion-weighted imaging (DWI), contrast-enhanced magnetic resonance imaging (CE-MRI) and positron emission tomography (PET) and to assess diagnostic accuracy, sensitivity and specificity.

28 patients with BIRADS 3-5 breast lesions detected by mammography or ultrasound were included in this IRB approved prospective study. All patients were examined with dedicated 18FDG-PET-CT and 3T MRI of the breast. Examinations were scheduled no longer than 7 days apart. MRI protocol included: 3D-1H-MRSI, DWI and a high resolution CE-3D-T1-w sequence before and after application of a standard dose Gd-DOTA. For PET-CT patients fasted at least 6 h before injection of approximately 300 MBq 18F-FDG based on the patients weight. A prone PET over the breasts was acquired allowing the same patient geometry as the breast MRI coil. CT data was used for attenuation correction. Co-registration of imaging data and image fusion were performed. PET-MRI was assessed for lesion morphology and EH-kinetics according to BIRADS, decrease ADC (threshold for malignancy 1.25 x10-3mm2/s), increased Choline-levels (SNR resonance  peak >2.55) and FDG-avidity. Lesions were classified as positive when FDG-uptake was greater than blood-pool activity. All lesions were histopathologically verified.

There were 19 malignant and 9 benign lesions. CE-MRI had a sensitivity of 100% and a specificity of 56%. Diagnostic accuracy was 86%. DWI had a sensitivity of 84% and a specificity of 78%. Diagnostic accuracy was 82%. MRSI had a sensitivity of 79% and a specificity of 100%. Diagnostic accuracy was 86%. PET had a sensitivity of 89% and a specificity of 67%.  Diagnostic accuracy was 82%. The combined use of all modalities achieved an excellent sensitivity of 95% and good specificity of 78% in the diagnosis of breast cancer. Diagnostic accuracy was 89%. The PPV was 0.9  and the NPV was 0.88.

Combined use of 3D-1H-MRSI, DWI, CE-MRI and PET in the assessment of breast lesions enabled an accurate breast cancer diagnosis with improved sensitivity, specificity and diagnostic accuracy and in breast biopsies would have been obviated in 11%.

By the combined use of 3D-1H-MRSI, DWI, CE-MRI and PET in the assessment of breast tumors unnecessary breast biopsies can be obviated.

Pinker, K, Bickel, H, Brück, B, Magometschnigg, H, Gruber, S, Bogner, W, Helbich, T, Combined Use of Proton MR Spectroscopy, Diffusion-weighted MR Imaging, Contrast-enhanced MRI, and PET in the Assessment of Breast Lesions: Initial Results.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11015533.html