How is rectal cancer treated?
Rectal cancer is treated slightly differently than colon cancer and that's because of the different blood flow that happens to the rectum. It's in a very tight area of the body where the blood flow does not necessarily go back into the liver and goes outside into the general circulation. The patterns of relapse for a rectal cancer are different than those for a colon cancer. For colon cancer, relapses usually occur in the liver or spread as at first to the liver. For rectal cancer there is a greater risk for a local cancer, in other words, in the tissues where the cancer was resected. Due to that, there's a role for radiation for rectal cancer whereas for colon cancer there usually is not a role for radiation. When somebody is diagnosed with a rectal cancer, usually they are started on neoadjuvant treatment which means treatment before surgery with both chemotherapy and radiation together. The radiation is given just locally to the rectum where the cancer is. The chemotherapy is usually given through the vein to help the radiation work better. After this neoadjuvant treatment, an individual goes to surgery because the rectal cancer then has been shrunk. Therefore surgery at that point is usually a less extensive surgery and depending upon the location of the rectal cancer, hopefully the anal sphincter can be spared.
