How is colon cancer diagnosed: First signs, risks and prevention

With subtle symptoms that are often overlooked, unhealthy lifestyles and irregular screening, the disease can spread fast and undetected

Unlike other cancers, the symptoms of colon cancer can be subtle and not immediately recognised. Accuray / Unsplash

Hollywood actress Kirstie Alley’s death at the age of 71 from colon cancer made headlines, not only because she was famous, but also because of the speed at which she died following her diagnosis.

Many cancers, such as colorectal or colon cancer, can be treated successfully with early detection. However, the symptoms of this particular kind of cancer can be subtle and easily missed if you’re not keeping an eye out for them.

“Colon cancer often does not have any symptoms and so can be detected quite late,” says Dr Ruhil Badiani, family physician at Cornerstone Clinic. “Screening tests can detect cancer before the symptoms develop and it is recommended that those with average risk start screening from the age of 45. Personal and family history is also important and some may be recommended to start screening at an earlier age.”

What are the early signs of colon cancer?

According to the Cleveland Clinic Abu Dhabi: “In the UAE, colorectal cancer is the most common cancer among males and the third most common cancer in females.”

It adds: “As it often has no symptoms early on, color​ectal cancer screening is vital. It can help detect cancer in its earliest stages, or even before it develops.”

While symptoms can differ from person to person, experts agree there are some common signs to look out for. A change in bowel habits as well as diarrhoea, constipation, or feeling that the bowel does not empty all the way are symptoms to look out for. Blood in the stool should be checked out immediately, along with unexplained abdominal pain, aches or cramps and weight loss.

“Colon cancer and rectal cancer are often grouped together because they have many features in common,” says the American Cancer Society. “Most colorectal cancers start as a growth on the inner lining of the colon or rectum. These growths are called polyps.”

How does colon cancer develop?

While not all polyps are cancerous, the two most likely to develop into the disease are adenomatous polyps (adenomas), sessile serrated polyps (SSP) and traditional serrated adenomas (TSA).

“Colon cancer can occur in anyone and there is no single cause of it,” says Dr Badiani. “Nearly all colon cancer starts as non-cancerous (benign) polyps which slowly develop into cancer.”

She adds: “When the cancer cells have been examined under the microscope, they assign a grade to it based on how abnormal the cells look. The more abnormal, the higher the number, the faster the cancer grows and spreads. How quickly it has spread is very much dependent on the grade of the cancer.”

How does lifestyle affect the risk of colon cancer? As with many other illnesses, genetics aside, lifestyle has a major effect on how likely it is that someone will develop colon cancer.

Age plays a factor, with those over the age of 45 at greater risk. Alcohol and tobacco also play a role, as does a diet which is heavy in processed foods and red meats.

“Lifestyle factors play a very large part in developing colon cancer,” says Dr Badiani. “Obesity, smoking, and a poor diet are common throughout the world and worsening. Westernised diets which are low in fibre and high in fat are becoming more popular throughout the world. The population is also ageing. This all leads to colon cancer being one of the most common cancers in men and women.” A family history of colon cancer, as well as existing inflammatory bowel diseases such as Crohn’s or ulcerative colitis can also influence the likelihood of cancer developing.

How to lower the risk of colon cancer

Diet and lifestyle are the two biggest factors in reducing the risk of colon cancer

“Maintain a healthy weight,” says Dr Badiani. “If you are at a healthy weight, work to maintain your weight by combining a healthy diet with daily exercise. Eat a variety of fruits, vegetables and whole grains. These contain vitamins, minerals, fibre and antioxidants, which may play a role in cancer prevention.”

Along with a healthy lifestyle, regular screening is a must to maintain colon and bowel health and is the most effective way to catch colon cancer early.

Dr Badiani adds: “Lifestyle changes are the most important risk factor that we can reverse.”