7 Signs of Colon Cancer - Know What to Look For

Do you know the signs of colon cancer? Being aware may save your life. Colon cancer is the third most common cancer in men and women across Europe and the USA. Read on and find out what to look out for.

The colon is another name for the large bowel and cancer can be found in different parts of the colon and the rectum (the end part of the large bowel often called the back passage). Sometimes you will hear the term colorectal cancer which is a term covering both areas or simply bowel cancer.

The over sixties are most at risk (9 out of 10 people with a diagnosis of colon or bowel cancer are over 60) but it can be diagnosed at any age. Survival rates are now good if the cancer is caught early so knowing what to look for is very important and when you discover those early signs of colon cancer you must act quickly. Ninety percent of people diagnosed will survive five years or longer if the cancer is caught early.

Signs of Colon Cancer Stages

Rectal Bleeding

If you find blood when you have a bowel movement then this is one of the signs of colon cancer. You may find blood on the toilet paper or you may see it in your stools. Yes it is a good idea to look! It might be mixed in or it could be on the outside. It might be bright red or it could be darker (darker blood comes from higher up).

Remember the color and where you saw it because all these things will give your doctor clues to help him or her decide what is going on.

It can be difficult to see what you are looking for in the toilet pan so a good tip is to open your bowels onto a large pad of folded toilet paper so you can inspect things more closely before flushing.

If I see blood does this mean that I have cancer? No, the blood may be a sign of other things like hemorrhoids but it is best to get it checked out because it is one of the signs of colon cancer.

Last year I noticed blood when I had a bowel movement. I felt worried as I knew this was one of the signs of colon cancer but I knew what I had to do.

I went to see my family physician who referred me to a specialist for tests. I was lucky and it turned out that the fresh blood that I saw on the paper when I wiped myself was caused by hemorrhoids. I was relieved but I am glad that I went straight away to get the checks, as I might not have been so lucky.

Sometimes the bleeding caused by colon cancer cannot be seen with the naked eye and this is why fecal occult (hidden) blood tests are offered by many countries in their healthcare programs. If this is offered to you do not hesitate to do the test.

You may also be offered the newer fecal immunochemical test which is now taking over as the test of choice. It may seem horrible to have to collect your own poop but a special applicator stick is provided. Only very small samples are needed and may be a life saver.

These test kits can also be bought privately for home use and it is a good idea for the over fifties to check regularly.

The recommendations for this vary between countries. For example every year in America, every two years in Australia, over the age of fifty.

If you have a history of this type of cancer in your family then take advice from your doctor as testing may need to start from age 40 and other screening tests such as a colonoscopy may be recommended.

A Change in Bowel Habit - The Commonest Sign of Colon Cancer

So now we get to diarrhea which is the main focus of this website. Of course most people with chronic diarrhea or diarrhea symptoms do not have colon cancer as there are many causes of diarrhea but if your bowel habits have changed and you have developed persistent loose stools or constipation or both which has lasted for longer than 3 weeks then you should seek advice.

If your back passage still feels full even after you have had a bowel movement you should ask for evaluation, as this is also one of the bowel cancer symptoms.

Another one of the signs of colon cancer to be aware of is stools that are thin and ribbon shaped. This shape can be a sign that the width of the bowel is narrowed by a growth or other obstruction.

So really think about what your personal bowel habits are like and if you have seen a change which has persisted for more than three weeks it is time to see your doctor. A change in bowel habit is one of the most common signs of colon cancer.


You may see mucus in your stools. This is a clear, sticky odorless secretion which is normally produced by the bowel to help the stools slip through but if the bowel is irritated then it may produce more which will be either on the outside of the stools or separate from them.

Abdominal Lump

Lumps in the abdominal area can be caused by many things but as they could be one of the signs of colon cancer they should always be checked out. You could just have a bad case of constipation or a hernia but you could have a cancerous lump. This is always something that should send you running to your doctor immediately.

Unexplained Weight Loss

Have you stepped on the scales recently and thought to yourself “that’s funny I have lost weight’ but you have not been eating any differently? This is a warning sign that something is not right. It is one of the signs of colon cancer and other illnesses too.

You could also be losing weight because you have lost your appetite, you are feeling sick or bloated, all possible bowel cancer symptoms. If you have lost weight and you have not been dieting then you need to have this checked out.


Anemia is caused by having too few red blood cells or low hemoglobin. When this happens the blood cannot carry enough oxygen and we will experience symptoms such as tiredness, breathlessness and dizziness.

Sometimes colon cancer is diagnosed when a routine blood test detects anemia which has been caused by bleeding at the site of the cancer in the bowel.
More often the patient will complain of feeling tired all the time.

If you have unexplained tiredness, if you are pale and especially if you have breathlessness and or dizziness then you should seek medical help.

Abdominal Pain

Strictly speaking abdominal pain is one of the bowel cancer symptoms not a sign (a sign is something you can observe, a symptom is something you experience) but it is very common when colon cancer is present. Of course abdominal pain can be caused by many other things.

If you suffer from constant or intermittent pain in the abdomen which may or may not be associated with going to the toilet or may be like cramps or colic then you should seek assistance.

You Now Know the 7 Main Signs of Colon Cancer but What Should You Do?

Having any one of these signs of colon cancer does not necessarily mean that you have it but obviously the more signs that you have the more likely it is. Only further tests arranged by your doctor will give you the answer.

We all worry when changes happen to our body and it is very easy to tell ourselves that if we ignore things that they will probably go away but this, although understandable is like gambling with our health.

If you see and experience changes that you cannot explain which could be signs and symptoms of colon cancer then it is always a good idea to get advice from your doctor.

If your main problem is diarrhea then this could be one of the signs of colon cancer but it could be caused by other things so browse this site for more information about the causes of diarrhea.

Return to Causes of Diarrhea from Signs of Colon Cancer

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