What is colon cancer?
Like all cancers, colon cancer begins when cells mutate and spread. Most colon cancers develop from adenomatous polyps – harmless clumps of cells that form inside the intestine. These polyps can develop into colon cancer at a later stage if they are not removed, and cancer cells may spread to other parts of the body (a process known as metastasis).
Colon cancer is sometimes grouped together with rectal cancer and called colorectal cancer. While no single cause has been identified, research has identified risk factors that include:
- Being over age 50
- Family history of colon cancer or polyps
- Personal history of colon cancer or polyps
- A high-fat diet
- Ulcerative colitis, Crohn’s Disease or other inflammatory bowel diseases
- Sedentary lifestyle
- Diabetes
- Obesity
- Smoking
- Alcohol
- Growth hormone disorder
- Radiation therapy for cancer
80% of those diagnosed with colon cancer have no family history or symptoms. Unfortunately, symptoms of colon cancer don’t tend to appear until it is quite advanced – making regular screening vital. The symptoms may also mimic those of other gastrointestinal conditions, so it’s important to get the correct diagnosis.
Symptoms include:
- Abdominal pain, tenderness or cramps in the lower abdomen
- Bloody stool, either bright red or very dark
- Diarrhea
- Constipation
- Changes in bowel function or stools, including stools that are narrower than normal
- Intestinal obstruction
- Unexplained anemia
- Unexplained weight loss
- Abdominal bloating
- Vomiting
- Polyps
Polyps do not generally cause symptoms themselves, but if you notice blood in your stool or on underwear or toilet paper after a bowel movement, or have constipation or diarrhea that lasts more than a week, see your doctor.
Treatment options for colon cancer depend on the stage of the cancer, whether it is a recurrence, and your general health. If your cancer is small, early stage and localized in a polyp, the gastroenterologist may be able to remove it all during a colonoscopy.
Often, partial colectomy surgery is performed, which removes the affected part of the colon and a margin of surrounding healthy tissue to ensure all the cancer is removed. It’s usually possible to reconnect the remaining parts of your colon, but if this isn’t possible, you will need a temporary or permanent colostomy bag to collect solid waste.
You may receive chemotherapy and/or radiation treatment as well to ensure any remaining cancer cells are destroyed. This will depend on where the cancer is located, how deeply it has penetrated the bowel and if it has spread to other areas of the body.