Fig. 2

Procedure for constructing a simulated PET image (histoPET). The histoPET was created from the histopathologic information matched to ex vivo CT (axial, sagittal, and coronal views from left to right). Delineation of PCa (=“1”) and non-neoplastic prostate tissue (=“0.1”) was performed at every histopathologic slice (top row). Note that the transaxial slice thickness of the pathological slices in this row was increased to 1 mm (from originally 2 μm) for illustration purposes only. The discretized histopathological slices were then used to approximate the entire PCa volume in a 4-mm slice (distance of histopathologic slices, middle row, see also step I) and smoothed in order to account for the limited spatial resolution of PET scans (bottom row, see also step III)