The 10 Signs Of Colon Cancer

Colon cancer is often associated with rectal cancer, and both conditions are grouped together as colorectal cancer. The condition affects about one in 23 men and one in 25 women¹. It is the second-most lethal cancer for men and women combined, and it is the third-leading cause of cancer deaths in men and women individually. 

Colon cancer is manageable when diagnosed early. So, it helps to know which signs and symptoms to look out for.

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What are the 10 signs of colon cancer? 

Colon cancer has a range of signs and symptoms, some of which are relatively uncommon. Ten of the most common and telling signs of colon cancer include: 

1. Changes in your stool's shape, color & texture 

Colon cancer can cause noticeable changes in your stool's shape, color, and texture. The stool tends to appear ribbon-like and has a thin, smooth texture. It may also appear blackish. 

2. Difficulty passing stools 

You may also find it difficult to pass stool even when you feel like going. Additionally, you may notice a disruption in your bowel habits. 

3. Rectal bleeding 

Colon cancer affects the colon walls and can cause open wounds. This results in rectal bleeding, which can range from mild to severe (and persistent over long periods). 

4. Blood in the stools 

Rectal bleeding is one of the common signs of colon cancer. The blood can become mixed with the stool in the rectum, resulting in blood-stained stools. 

5. Anemia

Rectal bleeding caused by colon cancer can be severe and persistent over long periods. It can result in significant blood loss over time, resulting in anemia.

6. Abdominal pain

Abdominal pain is one of the earliest and most common signs of colon cancer. It can also be accompanied by gas buildup and persistent cramps.

7. Weight loss

Cancer cells often release toxic substances that affect the digestive system and change how food is converted to energy. This often results in unwanted and unexplained weight loss.

8. Constipation

Constipation is one of the common changes in bowel movements in cases of colon cancer. Colon cancer can cause a person to have fewer than three bowel movements per week.

9. Diarrhea

Colon cancer can also cause diarrhea (very loose, frequent stools) rather than constipation. The symptom can be made worse by eating certain types of food. In this case, it is recommended to eat foods high in soluble fiber, such as oatmeal, white rice, and ripe bananas. Drink enough water to replace the lost fluids and prevent dehydration.

10. Vomiting

Colon cancer can result in the growth of tumors that block the bowel, obstructing the passage of food and waste. This often results in nausea and vomiting – it also discourages eating and contributes to weight loss.

When to visit a doctor

Colon cancer starts with mild symptoms that become worse over time. Some of these symptoms are barely noticeable until cancer has progressed for some time. Additionally, some of these symptoms are mild and common, and it is easy to mistake them for temporary pain or discomfort. For example, many people don't notice changes in their stools or give much thought to mild abdominal pain.

Fortunately, colon cancer is also one of the most treatable (and preventable) types of cancer. The disease has a survival rate of 91%² when diagnosed and treated at a localized stage.

You should visit a doctor as soon as you notice these or other symptoms associated with colon cancer. Ideally, you should call your doctor as soon as you experience abnormal abdominal pain and other symptoms such as blood in your stools.

It is also advisable to have regular cancer screening tests done for colon cancer and other diseases. Regular screening is especially advised if there is a history of colon cancer in your family.

Diagnosis & treatment of colon cancer

Colon cancer is easily treatable when diagnosed early. Diagnosis may require a series of tests. The initial test is a screening test designed to identify abnormalities such as the signs and symptoms discussed above. Other tests are:

  • Stool tests to check for blood 

  • Blood tests for tumor markers, liver enzymes, and complete blood count 

  • Diagnostic colonoscopy, proctoscopy, and biopsy 

  • Imaging tests, including CT scans, CAT scans, MRIs, x-rays, ultrasounds, and PET scans

Diagnosis and treatment are conducted by a range of colon cancer specialists, including:

  • Gastroenterologist (specializes in digestive and gastrointestinal disorders)

  • A surgical oncologist (specializes in surgery to treat cancer)

  • Colorectal surgeon (specializes in surgery to treat colon and rectum disorders)

  • Radiation oncologist (uses radiation therapy to kill cancer cells)

  • A medical oncologist (specializes in cancer medicines such as chemotherapy)

The lowdown

Colon cancer is preventable and highly treatable when diagnosed early. It is, therefore, advisable to take regular screening tests for early detection. Additionally, don't ignore these and other signs and symptoms related to the condition. 

Learn more about diagnosing and treating colon cancer.

Have you considered clinical trials for Colon cancer?

We make it easy for you to participate in a clinical trial for Colon cancer, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

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