Millions of adults avoid colorectal cancer screening. Don’t put your life at risk – get tested this March
March is National Colorectal Cancer Awareness Month, a time dedicated to raising awareness of a disease that affects 1 in 77 men, and 1 in 132 women in South Africa every year.1 Colorectal cancer (also known as bowel cancer) is the second most common cancer in men after prostate cancer, and the third most common cancer in women after breast and cervical cancer.1
Many people are unaware of the risks that colorectal cancer presents, while others don't like to talk about diseases that happen "down there." However, colorectal screening can accurately detect colorectal cancer long before the disease causes symptoms, and early detection may save lives.2
Survival is dependent on the stage of the disease at diagnosis. If the cancer is diagnosed at a localised stage, the survival rate is 91%.2 If the cancer has spread to surrounding tissues or organs and/or the regional lymph nodes, the 5-year survival rate is 72%.2 When colorectal cancer has already spread to distant sites by the time it is diagnosed, it is referred to as metastatic (stage IV) colorectal cancer, and the 5-year survival rate is 14%.2
“Colorectal cancer is one of the leading causes of malignancy related illness and death worldwide,” says Dr Thulo Molefi, Specialist and Senior Lecturer at the Department of Medical Oncology at Steve Biko Academic Hospital and the University of Pretoria. “The high incidence in Africa is thought to be related to high exposure to carcinogens such as processed meats, alcohol and smoking, as well as rising westernisation and sedentary lifestyles, resulting in obesity. South Africa doesn’t have a national screening program, however, based on international data we encourage everyone over the age of 50 to have a screening test. This will often include a colonoscopy, a physical examination and testing for blood not readily seen in the stool where necessary. Despite the difficulties potential patients experience in accessing cancer screening services in South Africa, particularly in the public health sector, it's prudent that people at risk seek out such services, as detecting colon cancer at its early stages leads to better disease outcomes.”
What is the colon?The colon and rectum make up the large intestine, which is part of the digestive system.3 Most of the large intestine is made up of the colon which consists of four sections, namely:3
- The ascending colon which extends upward on the right side of the abdomen.
- The transverse colon which goes across the body from the right to the left side.
- The descending colon which travels down on the left side of the body.
- The sigmoid colon which joins the rectum and connects to the anus.
What are the risk factors for colorectal cancer?
There are a number of risk factors for colorectal cancer, including:
Lifestyle: Alcohol and smoking both increase the risk of bowel cancer.3
Age: As a person’s age increases, so does their likelihood of developing bowel cancer. Most people with colorectal cancer are over the age of 50, and the risk of having the disease increases with age.4
Bowel disease: People with inflammatory bowel disease (IBD) have a higher risk of developing bowel cancer than the general population. The risk increases with extent and duration of IBD.4
Genetics: There are some rare inherited conditions or syndromes associated with certain gene changes. Family members have an increased risk of bowel cancer if they inherit these gene changes and if they are a blood relative with the disease.4,5
Being overweight: Being obese or overweight increases the risk of bowel cancer. Try to keep a healthy weight by being physically active and eating a healthy, balanced diet. There is compelling evidence showing a lower risk of bowel cancer in people who are more physically active.4,5
“You can decrease your risk of colorectal cancer by improving your lifestyle,” says Dr Molefi. “Regular exercise and a diet that includes lots of vegetables, fruits, and whole grains have been linked to a decreased risk of colorectal cancer. It’s wise to eat less red meat and processed meats which have all been linked to an increased risk of colorectal cancer. We also recommend decreasing the amount of alcohol you consume. For cancer prevention, it's best not to drink alcohol at all.”
How does colorectal cancer start?3Most colorectal cancers start as a growth, called a polyp, on the inner lining of the colon or rectum. Certain types of polyps may change into cancer over time, but this usually occurs after many years. Cancer is when abnormal cells start to divide and grow in an uncontrolled way. The cells can grow into surrounding tissues or organs and may spread to other areas of the body.
What are the symptoms?People with colorectal cancer may not experience symptoms in the early stages. When symptoms appear, they usually vary, depending on the cancer’s size and location in the large intestine.
Common symptoms may include4:
a change in bowel habit, such as diarrhoea, constipation, or smaller, more frequent bowel movementsa change in appearance of bowel movements i.e., narrower stools or mucus in stoolsa feeling of fullness or bloating in the abdomen or a strange sensation in the rectum, often during bowel movementa feeling that the bowel hasn’t emptied completelyblood in the stools or on the toilet paperunexplained weight lossweakness or fatiguerectal or anal paina lump in the rectum or anusabdominal pain or swellinga low red blood cell count (anaemia), which can cause tiredness and weakness
Treatment optionsIf you experience any signs or symptoms of colorectal cancer, you should consult your doctor. A colonoscopy is a procedure where a fibre-optic camera is inserted through the anus in order to examine the colon.4 If colorectal cancer is suspected, a biopsy of abnormal tissue will be obtained during a colonoscopy.4
Treatment will depend on how far the cancer has advanced and may include surgery, radiation, and chemotherapy, or a combination of these.
If the cancer has spread or cannot be removed by surgery, you may be a candidate for targeted therapy. Targeted therapy drugs target specific molecules within the cancer cells to stop their growth.4
Your doctor will develop a treatment plan that’s right for you based on the location of the cancer, whether the cancer has spread, your general health and preferences, and ultimately, what will lead to the best outcome.
For more information, visit: https://merckpatientoncology.co.za/colorectal-cancer/
1. The Cancer Association of South Africa (CANSA). Colorectal Cancer. [Feb 2023]. Available at: https://cansa.org.za/colorectal-cancer/
2. Cancer.Net. Colorectal Cancer Statistics. [Feb 2023]. Available at: https://www.cancer.net/cancer-types/colorectal-cancer/statistics#:~:text=rate%20is%2091%25.-,If%20the%20cancer%20has%20spread%20to%20surrounding%20tissues%20or%20organs,rate%20for%20people%20is%2067%25
3. American Cancer Society. About Colorectal Cancer. [Feb 2023]. Available at: https://www.cancer.org/cancer/colon-rectal-cancer.html
4. Cancer Council. Understanding bowel cancer: a guide for people with cancer, their families and friends. January 2019 Edition. Available at www.cancer.org.au.5. Cancer Research UK. Bowel cancer risk factors. . [Feb 2023]. Available at: https://www.cancerresearchuk.org/about-cancer/bowel-cancer/risks-causes