Fig. 2
Examples of ROI segmentation in pancreatic ductal adenocarcinoma (PDAC) using 18F-FDG PET/CT images. One physician segmented tumor in blue along the edge of tumor (above), and the other physician segmented tumor in green to include voxels presenting SUV values greater than 50% of SUVmax (below). a The axial CT (above) and fusion (below) images of grade 3 (2010 World Health Organization classification system) PDAC in a 69-year-old man. The images showed a mass measuring about 3.7 × 3.4 × 2.8 cm with SUVmax of 3.7 in pancreatic head. b The axial images of grade 2 PDAC in a 57-year-old man. The image showed a mass with necrotic lesion in tail of pancreas, and SUVmax was 4.1. c The axial images of grade 1 PDAC in a 56-year-old man. The images showed a mass measuring about 2.7 × 2.7 × 2.8 cm with SUVmax of 3.0 in pancreatic body