Registration between MRI and spot mammograms: results and applicability for x-ray guided biopsy of MRI only lesions

Breast cancer is the most common type of cancer among women worldwide. Contrast-enhanced magnetic resonance imaging (CE-MRI) is routinely used to find suspicious lesions in breasts, which are not visible on mammography. These lesions need to be further evaluated using an MRI-guided biopsy. MRI-guided biopsy is not available everywhere, and it is expensive and time-consuming. A novel method was proposed in our earlier work for matching between magnetic resonance imaging (MRI) and spot mammograms. Having such a method would allow biopsying lesions, which are only visible in MRI, by the widely available and cheaper X-ray guided biopsy. Two registration methods have been developed to achieve this goal: a biomechanical model-based registration between MRI and full X-ray mammograms, followed by an image-based registration between full and spot mammograms. In this paper, we focus on evaluating the cumulative registration of the two methods using 51 patients from the Medical University of Vienna. We also simulate and assess whether the biopsy needle hits the predicted position of the lesion. The median target registration error (TRE) achieved is 35.6mm. For 11 or 14 of the 51 datasets, an X-ray guided biopsy would be successful when extracting 12 or 24 specimens with a standard needle biopsy, respectively.