Overview

Colorectal cancer, also known as colon cancer, is a type of cancer that affects the colon and rectum. It is usually caused by the abnormal growth of cells in the colon or rectum, which can form a tumour. The most common symptoms include rectal bleeding, abdominal pain, changes in bowel habits, and unexplained weight loss. Colon cancer is usually diagnosed with a combination of tests such as a colonoscopy, stool tests, and imaging studies like X-rays or CT scans. The treatment options for colon cancer may include surgery, chemotherapy, radiation therapy, or a combination of these. It is important to get screened for colon cancer starting at age 50, or earlier if there is a family history of the disease.

Causes

The exact cause of colon cancer is not known, but several risk factors have been identified, including:

• Age: The risk of colon cancer increases as people get older.
• Family history: People with a family history of colon cancer have an increased risk of developing the disease.
• Lifestyle factors: Poor diet, lack of physical activity, obesity, and tobacco use can increase the risk of colon cancer.
• Chronic conditions: Inflammatory bowel disease (IBD), such as Crohn’s disease or ulcerative colitis, can increase the risk of colon cancer.
• Polyps: Certain types of polyps (growths in the colon) can turn into cancer over time.
• Personal history: People who have had colon cancer before are at increased risk of developing the disease again.

It is important to talk to a doctor about the risk factors and to get screened for colon cancer starting at age 50, or earlier if there is a family history of the disease.

Symptoms

The symptoms of colon cancer may include:

• Changes in bowel habits: This can include constipation, diarrhoea, or a change in the consistency of stools.
• Rectal bleeding: Blood may be seen in the stool or on toilet paper after wiping.
• Abdominal pain: Pain may be felt in the abdomen or the rectum.
• Unexplained weight loss: People with colon cancer may lose weight without trying.
• Weakness or fatigue: People with colon cancer may feel weak or tired.
• Anaemia: A low red blood cell count can cause weakness and fatigue.

Other conditions, such as haemorrhoids, can cause similar symptoms. It is important to see a doctor if any of these symptoms persist for more than a few weeks. A doctor can determine the cause and recommend the appropriate treatment.

Diagnosis

Diagnosis of colon cancer usually involves a combination of tests, including:

1. Colonoscopy: This is a procedure in which a doctor uses a flexible scope to examine the inside of the colon and rectum.
2. Stool tests: Stool samples may be tested for blood, which can be a sign of colon cancer.
3. Imaging tests: X-rays, CT scans, or MRI scans may be used to visualize the inside of the colon and rectum.
4. Biopsy: A small sample of tissue may be removed during a colonoscopy and tested for cancer cells.

There’s need to talk to a doctor about the appropriate screening tests based on age, risk factors, and personal and family medical history. It is also necessary to follow recommended screening guidelines, as early detection is key to successful treatment of colon cancer.

Treatment

Treatment options for colon cancer may include:

• Surgery: This is the most common treatment for colon cancer. The goal of surgery is to remove the cancer and a portion of the healthy tissue surrounding it. The type of surgery will depend on the location and size of the tumour.
• Chemotherapy: This treatment uses drugs to kill cancer cells. Chemotherapy may be given before or after surgery, or as a standalone treatment.
• Radiation therapy: This treatment uses high-energy radiation to kill cancer cells. Radiation therapy may be given before or after surgery, or as a standalone treatment.
• Targeted therapy: This treatment uses drugs that target specific genetic changes in cancer cells.
• Immunotherapy: This treatment uses the body’s immune system to fight cancer.

The specific treatment plan will depend on the stage and type of colon cancer, as well as the overall health of the patient. A team of specialists, including a surgeon, medical oncologist, and radiation oncologist, will work together to determine the best course of treatment.

Related: colon cleanse benefits and risks

Prevention

There is no sure way to prevent colon cancer, but there are steps that can be taken to reduce the risk:

• Get screened: Regular screening starting at age 50 is the best way to detect colon cancer early, when it is most treatable. People with a family history of the disease may need to start screening at an earlier age.
• Eat a healthy diet: A diet high in fruits, vegetables, and whole grains, and low in red and processed meats, can reduce the risk of colon cancer. (see 10 best colon-cleansing foods)
• Exercise regularly: Physical activity can help maintain a healthy weight, which can reduce the risk of colon cancer.
• Don’t smoke: Smoking can increase the risk of colon cancer, as well as many other health problems.
• Limit alcohol consumption: Heavy alcohol use can increase the risk of colon cancer.
• Maintain a healthy weight: Being overweight or obese can increase the risk of colon cancer. A healthy diet and regular exercise can help maintain a healthy weight.
• Manage chronic conditions: Chronic conditions such as inflammatory bowel disease (IBD) can increase the risk of colon cancer. It is important to manage these conditions with the help of a doctor.

Early detection is key to successful treatment of colon cancer. It is also important to talk to a doctor about the appropriate screening tests and schedule regular check-ups based on age, risk factors, and personal and family medical history.