METASTASIS

• If patient has colorectal carcinoma, because the venous drainage of the intestinal tract is via the portal system, the first site of hematogenous dissemination is usually liver, followed by lungs, bone, and many other sites, including brain [25]
• If the tumor arises in the distal rectum, it may metastasize initially to the lungs because the inferior rectal vein drains into the inferior vena cava rather than into the portal venous system [25]