1. Method of processing X-ray images of a breast, the method comprising the steps of: generating a 3D volume from a plurality of X-ray images, the 3D volume comprising a set of parallel slice images distributed along a main axis, the method being characterized in that it further comprises the steps of processing the 3D volume and/or the plurality of X-ray images so as to detect at least one region of interest in the breast, computing, for each region of interest in the 3D volume, a 3D characteristic position of the region of interest, computing at least one needle target 3D position from a plurality of said computed 3D characteristic positions, each needle target 3D position being a position where tissue contained in corresponding regions of interest can be sampled therefrom, associating each needle target position with a target image, said target image being determined from comparing the needle target position with positions of the slice images along the main axis, displaying a slice image on a graphical interface, and if the current slice image is a target image, displaying on the graphical interface a target marker indicating each needle target position associated with the displayed current slice image.