colon cancer
Colon cancer starts in cells that line the inside of the colon. Colorectal cancer, which includes colon and rectum cancer, is the second leading cause of death from cancer in men. It represents about 11% of all cancers diagnosed in Canada. Approximately 1 in 14 men will develop colorectal cancer. The good news is that these rates are declining, likely due to increased colorectal cancer screening, which can identify and remove precancerous polyps.
There are a few different types of colon cancer. The most common one is adenocarcinoma, where cancer develops from the surface of the lining in the colon itself.
Causes
Colon cancer, like all cancers, has many causes. One of the primary risk factors is having first-degree relatives who have had colon cancer. The age when your relatives developed colon cancer is an important factor that helps determine your risk level, especially when they developed colon cancer before the age of 60.
Males are at a higher risk than females; about 1 in 14 males will develop colon cancer in their lifetime, while one in 18 females will develop colon cancer.
Other bowel conditions, like ulcerative colitis or Crohn’s colitis, can potentially put one at an increased risk of colon cancer.
Prevention
About 4 in 10 cancer cases can be prevented through healthy lifestyle choices. You can also reduce your risk of cancer right now if you start to make positive lifestyle changes that will make you feel better and live longer.

Get Active
It is important to try and get 30 minutes of moderate physical activity every day. If you sit a lot during the day, remember to take short, frequent breaks to get your body moving.
Going outside and getting active on sunny days will help increase your vitamin D levels. Vitamin D is important because it helps to create a healthy immune system. The healthier your immune system is, the better your body is at discovering abnormal cells that your body can take care of before they potentially become a problem.
Eat Healthier
Eat cruciferous vegetables like broccoli and Brussels sprouts to help protect against colon cancer. Reduce red meat and processed meat, like salami.
Eating a high fibre diet is a great way to add bulk to your stool, so that food waste passes through your system quickly. On its way out, it removes toxins and carcinogens from your system. This reduces your risk of colon cancer.


Drink Less
Drinking alcohol increases your risk of colorectal cancer. Drinking 3.5 drinks a day increases your risk of developing colorectal cancer and breast cancer by 1.5 times. The less alcohol you drink, the more you reduce your risk of developing cancer.
If you do drink alcohol, have 2 or less drinks a day for men. With no more than 3 drinks in one sitting, and take at least 2 days off a week.
Stop Smoking
Smoking is responsible for an estimated 30% of all cancer deaths in Canada. 72% of lung cancer cases are caused by smoking tobacco. It’s never too late to start quitting. Take it one day at a time and know that quitting now does reduce your risk of cancer.

Diagnosis
The best way to prevent colon cancer is to screen for it, and there are two ways you can get screened.
- Fecal immunochemical test (FIT). This is a stool test that looks for microscopic blood because sometimes polyps can bleed. This FIT test is done when you are feeling well and have no symptoms. Having a positive FIT test doesn’t necessarily mean you have cancer, and it also doesn’t necessarily mean you have polyps, but the likelihood of you having a polyp is greater. If a FIT test finds microscopic blood, you will then do a colonoscopy.
- Colonoscopy. A colonoscopy requires you to prepare your bowels by drinking fluids that your doctor will give you to flush out your stool. Your doctor will take a tube with a camera on its end to look into the bowel to see if there are polyps and will then remove them. It’s not a particularly painful procedure. In many places, the procedure is done with some sedation, but most patients fall asleep during the process.
Before someone has colon cancer, they develop polyps (i.e., small clumps of cells) in their bowels. Non-cancerous polyps don’t cause symptoms, so you won’t feel anything if you have them. However, after quite a long time – at least five years – the polyp will slowly turn into cancer.
You can prevent cancer by screening, identifying polyps, and removing them before they turn into cancer.
A person who is considered average risk is a 50 year old male or female who has no family history, no other medical conditions that increase their risk of colon cancer, and does not have symptoms. In this case, the FIT test is best for screening for polyps and preventing cancer.
Higher-risk individuals i.e., those with a family history, have ulcerative colitis, or have a history of polyps, will need a colonoscopy.
Signs & symptoms
Not all of the symptoms below necessarily mean you have colon cancer since they can also be indicative of other issues. It’s always important to speak to your doctor if you are experiencing any of the problems below on an ongoing basis because they are potentially a reason to investigate the symptoms further.
The type of symptoms that doctors are most concerned with are:
- A change in your bowel routine. A normal bowel routine – for the most part – is whatever is normal for you. However, three bowel movements a day to three bowel movements a week is normal for the general population. If you usually have a bowel movement three times a day and are now having a bowel movement every other day, that is of concern.
- A change in the shape or look of stool. Particularly if it’s consistently different from what the patient is used to.
- Blood with or around the stool.
- Abdominal pain. There are many reasons for abdominal pain; colon cancer is only one of many.
- Weight loss. If you are not trying to lose weight, losing 10 percent of your body weight over six months is something to talk to your doctor about.
Treatment
Cancer is when cells divide abnormally without proper control. Colon cancer can spread to other places such as the lymph nodes and the lymphatic system in that area. It can also spread to other organs, with the most common one being the liver. Patients won’t necessarily know it has spread until after the surgery when doctors have looked at the specimen under a microscope.
- Surgery. If colon cancer is identified early enough and it hasn’t spread anywhere else, the lesions can be removed in surgery. This surgery can cure colon cancer.
- Chemotherapy. Further treatment can be offered through chemotherapy, which is designed to kill rapidly dividing cells to prevent them from growing further and causing problems.
- Radiation therapy. This treatment uses high-energy rays (such as x-rays) or particles to destroy cancer cells. If someone has cancer very low in their bowel, i.e., the rectum, radiation is an option to help manage cancer. Often, it is used alongside chemotherapy.
Surgery is almost always part of colon cancer’s treatment strategy. Chemotherapy would be an additional strategy to help prevent it from coming back or causing problems.
Coping
Having this diagnosis is very challenging to deal with, without a doubt. What’s important to help cope with diagnosis is reaching out to friends, family, and provincial cancer support specialists. There are resources available to connect with experts whose professional lives are dedicated to helping colon cancer patients through this very troubling time in their life.
The most important point about coping with diagnosis is not to keep it in. Communicate what is of concern to you so that you can get the support you need from friends and family. It’s also important to learn how to properly take care of yourself after diagnosis.
Frequently asked Questions
How serious is colon cancer?
The diagnosis of cancer is serious, no matter what that cancer is.
Can colon cancer kill you?
Unfortunately, it can. In non-smokers, it’s the leading cause of cancer death (for smokers, the leading cause of cancer death is lung cancer).

A Guy’s
Guide to Eating
Healthy
Start eating healthier today with simple dietitian recommendations, healthy meal ideas, and cost-saving tips.
Download the free guide now!
