http://pathways.nice.org.uk/colorectal-cancer.
In colorectal cancer, cells in the colon or in the rectum start to grow in an uncontrolled way, forming a lump called the primary cancer or primary tumour. Like other cancers, colorectal cancer starts in a small area but can spread to other parts of the body to form metastatic tumours.
The term colorectal cancer covers cancers in both the colon (colon cancer) and the rectum (rectal cancer).uk/pathways/colorectal-cancer.
UPDATED EVIDENCED BASED DOCUMENT.
G.MOHAN