Colon cancer is caused by the uncontrolled growth of cells in the colon. It may take years to develop, and at the early stage, there may only be an abnormal growth of tissues known as polyps. However, these polyps can then develop into cancer if left untreated or not removed.
Risk Factors for Colon Cancer
Although the exact cause of colon cancer is unknown, there are some risk factors that may increase the chance of developing the disease.
- Personal history of polyps: These are usually found on the wall of the large intestine and are not malignant. However, over time some of these polyps can develop into colon cancer.
- Age: While colon cancer can be found in younger people and teens, it is much more common in older people. 90% of cases involve people over the age of 50.
- Personal history of IBD (inflammatory bowel disease): Ulcerative colitis and Crohn’s disease are more commonly known as IBD (inflammatory bowel disease) and increase the risk for developing colon cancer.
- Family history of colon cancer: Having a family member under the age of 60 years with colon cancer increases the risk of colon cancer.
- Obesity and lack of exercise: There is evidence to suggest that the risk of developing colon cancer may higher in people who are overweight and do not exercise regularly.
- Smoking: Studies have reported that the risk of colon cancer is higher among smokers than non-smokers.
Symptoms of Colon Cancer
In some cases, people with colon cancer have no abnormal symptoms, so they do not know that they have cancer. Also, there are other diseases with similar symptoms, which can confuse the issue. However, it is important to seek medical attention when the following symptoms appear:
- Diarrhea, constipation or bloating
- Blood, bright red or very dark, in the stool
- Narrowing of stools
- Abdominal discomfort, burning sensation, bloating and clamping
- Unexplained weight loss
- Fatigue or weakness
Colon Cancer Screening
Colon cancer screening is a method of helping to prevent colon cancer by find the polyps before they turn into cancer. Men and women should begin screening at age 50. The screening can be performed in the following ways:
- Fecal Occult Blood Test (FOBT) is a test that looks for the presence of polyp or cancer cells. Annual testing with this method significantly reduces colon cancer mortality, while biennial testing reduces mortality rates from colon cancer by 18%.
- Sigmoidoscope is a procedure where a doctor inserts a tube through the anus to the lower part of the colon so as to examine for polyps, abnormalities and cancer. Using this method, the doctor can cut any abnormal polyps and extract them for further examination.
- Colonoscopy enables visual inspection of the entire large bowel and specimen collection for biopsy.
- Double Contrast Barium Enema (DCBE) and CT Scan are alternative methods when patients cannot undergo colonoscopy.
Diagnosis of Colon Cancer
Doctors use a range of tests to diagnose cancer and determine if it has spread to other organs. The method of diagnosis varies depending on several factors, such as age and health of the patient, type of cancer, severity of symptoms and earlier test results. Diagnosis of colon cancer can be performed in the following ways:
- Biopsy, which involves taking small amounts of tissue samples from the patient, is the most accurate method of detecting colon cancer and providing biomolecular predictors of cancer.
- Carcinoembryonic Antigen (CEA) is a blood test used to determine the amount of red blood cells or measure the amount of a protein.
- CT Scan is used to find the location of the cancer and determine how far it has spread to other parts of the body.
- Ultrasound uses high frequency sound waves to determine how much the cancer has spread to the lungs or other organs.
- Chest X-ray is used to determine how much the cancer has spread to the lungs.
- PET Scan is a test that involves the injection of a radioactive substance into an organ or tissue in order to create images that can be examined.
Treatment of Colon Cancer
Treatment of colon cancer requires a multidisciplinary team of physicians such as surgeons, radiologists and cancer specialists who together will make the most suitable treatment plan for each individual patient. The doctors will make their decision based on the following factors:
- Size, location and characteristics of the cancer cells
- Stage of disease and spread of cancer
- Patient’s general health
Treatment Options for Colon Cancer