CT and histological sections of mouse bladders with space-filling tumors. (A) Sequential whole body axial slices from FPDCT scans taken at three time points (24, 28, and 32 weeks of age) were cropped to select the bladder, with the lumen filled with a radiopaque agent and appearing lighter than the surrounding tissue. Areas of radiopaque exclusion in the lumen are indicated with arrows. Animals were either sham-operated, castrated + DHT pellet, or castrated within one week after the initial 24-week FPDCT scan. Tumor volumes were calculated from the difference in area in each slice after thresholding to select the bladder area and the Omnipaque™-filled area. (B) Hematoxylin/eosin stained sections of bladders from UPII-SV40T male intact, castrate + DHT pellet, and castrate mice. 100× original magnification.