Where does colorectal cancer affect before metastasis?

Mesenteric nodes: As colon cancer grows from premalignant cells in the mucosa of bowel it invades the muscularis reaching serosal outer surface (Dukes B). It then invades nodes of the mesentery C1 expanding to 4 or more nodes C2 and then along the mesenteric lymphatics to liver. Subpopulations in the primary however can eventually spread directly to lung or bone depending on their surface antigens.