Rectal cancer is cancer that begins in the rectum. The rectum is the last several inches of the large intestine. It starts at the end of the final segment of your colon and ends when it reaches the short, narrow passage leading to the anus.
Cancer inside the rectum (rectal cancer) and cancer inside the colon (colon cancer) are often referred to together as “colorectal cancer.”
According to the American Cancer Society, colorectal cancer disproportionately affects the Black community, where the rates are the highest of any racial/ethnic group in the US. Blacks are about 20% more likely to get colorectal cancer and about 40% more likely to die from it than most other groups.
Signs and symptoms of rectal cancer include:
Rectal cancer can be found during a screening test for colorectal cancer or a diagnosis can be based on your symptoms.
Rectal cancer begins when healthy cells in the rectum develop changes (mutations) in their DNA. A cell’s DNA contains the instructions that tell a cell what to do.
The changes tell the cells to grow uncontrollably and to continue living after healthy cells would die. The accumulating cells can form a tumor. With time, the cancer cells can grow to invade and destroy healthy tissue nearby. Cancerous cells may also break away and travel (metastasize) to other parts of the body.
In many rectal cancers, it’s unclear what causes the mutations that cause the cancer to form.
Gene mutations may be passed from parents to children and increase the risk of colorectal cancer. However, these mutations are involved in only a small percentage of rectal cancers. Some genes linked to colorectal cancer increase the risk of developing the disease, but they don’t make it inevitable.
The following are genetic colorectal cancer syndromes are:
Either of these syndromes other, rarer inherited colorectal cancer syndromes can be detected by genetic testing. If you have a family history of colon cancer, you should talk with your doctor about your risk factors.
Factors that may increase the risk of rectal cancer are the same as those that increase the risk of colon cancer. Colorectal cancer risk factors include:
In the past, long-term survival was uncommon for people with rectal cancer, even if they had extensive treatment. However, treatment advances over the last few decades have caused rectal cancer survival rates to greatly improve.
Rectal cancer treatment often involves a combination of therapies. When possible, surgery is used to cut away the cancer cells. Other treatments, such as chemotherapy and radiation therapy, may be used after surgery to kill any cancer cells that remain and reduce the risk that your cancer returns.
If surgeons are concerned that the cancer can’t be removed completely without hurting nearby organs and structures, your doctor may suggest a combination of chemotherapy and radiation therapy as your initial treatment. These combined treatments can shrink the cancer making it easier to remove during an operation.
To reduce your risk of colorectal cancer, consider trying to:
Although rectal and colon cancers are similar in many ways, their treatments are quite different. This is mainly because the rectum sits in a tight space, barely separated from other organs and structures. The tight space can make surgery to remove rectal cancer complex.
