Hubert Bickel MD, Presenter: Nothing to Disclose

Katja Pinker-Domenig MD, Abstract Co-Author: Nothing to Disclose

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

Heinrich Magometschnigg, Abstract Co-Author: Nothing to Disclose

Michael Weber, 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 assess if diffusion weighted imaging (DWI) at 3T can serve as a non-invasive biomarker for breast tumor malignancy and invasiveness.

233 consecutive patients with 279 suspicious breast lesions detected in routine breast screening (BI-RADS® 3-5) were examined. All examinations were performed before any intervention and histopathological verification was obtained in all patients after the MRI. A 3T Scanner with a dedicated 4-channel breast coil and a standardized measurement protocol was used for the examinations. The protocol consisted of a T2-weighted, a dynamic contrast enhanced (DCE) T1 and a diffusion weighted sequence using b-values of 50 and 850. ADC maps were calculated and 2-dimensional ROIs were drawn in the area with the lowest ADC-values. An ADC-threshold of 1.25×10-3mm²/s was used. ADC-values below this threshold were considered as malignant. Mean values were compared using ANOVA and Games Howell post hoc test and sensitivity and specificity were calculated.

The mean ADC-values were 1.58×10-3mm²/s for the benign lesions, 1.24×10-3mm²/s for the ductal carcinomas in situ (DCIS), 0.91×10-3mm²/s for the invasive ductal (IDC), 0.86×10-3mm²/s for the invasive lobular carcinomas (ILC) and 1.62×10-3mm²/s for the invasive mucinous carcinomas. ADC-values were significantly lower in all malignant subtypes, except mucinous carcinomas, compared to the benign tumors. The ones for DCIS were significantly higher than those for most common the invasive types (IDC and ILC) while no significant difference was found between the latter two. Overall sensitivity was 92.2% and specificity was 90.1%.

DWI at 3T is a powerful biomarker, which allows the non-invasive differentiation between invasive and non-invasive breast cancer. Also, benign and malignant breast tumors can be differentiated with high sensitivity and specificity.

DWI provides information that is crucial for therapy decision and might be, combined with other imaging methods, another step towards a non-invasive gold standard for breast tumor evaluation.

Bickel, H, Pinker-Domenig, K, Bogner, W, Magometschnigg, H, Weber, M, Helbich, T, Diffusion-weighted Imaging: A Noninvasive Biomarker for Breast Cancer Invasiveness.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12036598.html