This is a contrast-enhanced CT image showing a segment of focal circumferential wall thickening in the sigmoid colon. This is the CT-equivalent of the apple core sign we see at barium enema, typical of primary colorectal carcinoma.
Primary tumor post-treatment image:
Note that the wall thickening is much less apparent. One could easily miss this primary tumor if the post-treatment image was the only image available.
Liver pretreatment image:
This is a single image from a contrast-enhanced CT showing a large, probably 5-cm suspicious hypodense mass in segment VII, abutting both the IVC and the right hepatic vein. This is in a somewhat difficult location surgically.
Liver post-treatment image:
The lesion has shrunk substantially and has pulled away from both of those venous structures, at least in part.
