Synchronous Colorectal Carcinomas
Colorectal cancer. This is an example of ‘synchronous’ colorectal carcinomas. The image on the left shows circumferential thickening of the wall of the descending colon, while on the right there a polypoid soft tissue mass protruding into the lumen of the upper rectum. The presence of two or more tumours at the same time occurs in 2 to 5% of cases of colorectal cancer, however this figure rises to up to 20% in patients with risk factors such as familial adenomatous polyposis.