Colon cancer happens when cancer tumors form in the large intestine. Usually, there are no symptoms early on. So, it’s important to see a doctor if you notice any lasting changes in your bowel habits.
The colon or large intestine is where the body pulls water and salts from solid waste. Then, the waste moves through the rectum and leaves the body through the anus.
Health experts recommend regular screenings forcolon and rectal cancer for adults aged 45-75, since this cancer is the third most common worldwide.
This article covers colon cancer symptoms, causes, how it’s diagnosed, and treatment options.
Colon cancer symptoms
Colon cancer often has no symptoms in early stages, but symptoms get clearer as it progresses. Early symptoms people might notice include:
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Blood in the stool.
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Change in how often or the type of bowel movement, like diarrhea or constipation, or narrow stool that looks like a ribbon.
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Feeling like you haven't fully emptied your bowels, even after using the bathroom.
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Stomach pain, cramps, or bloating.
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Vomiting and nausea.
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Anemia Due to intestinal bleeding.
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Loss of appetite.
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Constant fatigue and weakness.
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Unexplained weight loss.
Also, more advanced symptoms of colon cancer might include these:
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Dark brown or black stool with blood present.
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Bright red bleeding from the rectum.
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Stomach pain, cramps, bloating, and gas.
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A constant urge to poop, even after going.
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Continued weight loss.
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Iron deficiency anemia.
Also, when colon cancer spreads to other parts of the body, like the liver, it can cause extra symptoms like jaundice. Some women might have irregular periods.
Stages of colon cancer
There are different ways to define the stage of colon cancer. The stages show how far the cancer has spread and the size of the tumor. Stages of colon cancer can include:
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Stage zeroThis stage means the cancer is just in place. It's very early and hasn't grown past the inner layer of the colon. Usually, it's easy to treat.
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Stage oneThis stage means the cancer started to grow into the next layer of tissue in the colon.
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Stage TwoThis stage means the cancer has reached the outer layers of the colon but hasn't spread outside the colon.
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Stage ThreeThis stage means the cancer started to grow outside the colon and reached 1-3 lymph nodes but hasn't spread far in the body.
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Stage FourThis stage means colon cancer has spread to other parts of the body like the liver.
Causes of Colon Cancer
Usually, body cells follow an ordered process of growth, division, and death. Cancer happens when cells grow and divide abnormally and can’t be controlled. Also, these cells don’t die when they normally should in their life cycle.
Research shows the real cause of colon cancer isn't clearly known, but many factors can raise the risk.
Cancer happens due to changes in DNA inside cells. Some genes called oncogenes help cells survive, grow, and divide abnormally and uncontrollably. This can lead to many genetic changes that cause colon cancer.
Risk factors that may increase colon cancer include:-
- Polyps
Colon cancer can develop from precancerous polyps growing in the large intestine. Some polyps can turn into malignant colon cancer if not removed early.
These polyps can include:-
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Adenomas.
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Hyperplastic polyps.
- Genetics
About 5-10% of colon cancers come from specific inherited cases that raise the risk of cancerous polyps, like colon cancer, and other cancers in some family members.
- Some medical conditions
Some conditions and treatments can raise the risk of colon cancer, These conditions include:-
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History of benign tumors.
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Inflammatory bowel diseases, like ulcerative colitisand Crohn's disease.
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Other cancers, like cancer of the breast and the ovary andthe uterine lining.
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weight gain andObesity.
- Other Risk Factors
Other risk factors for colon cancer can include:-
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Having a family member with a history of colon or rectal cancer.
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Eating large amounts of saturated fats.
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Getting older, but colon cancer is becoming more common in people under 50.
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Alcohol use.
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Eating processed foods and meats.
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Lack of physical activity.
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Smoking.
Also, since the colon is part of the digestive system, diet and nutrition play key roles in colon cancer development.
Colon cancer diagnosis
To diagnose colon cancer, the healthcare provider will do a full physical exam and ask about personal and family medical history. Other diagnostic techniques can also be used to identify colon cancer and its stages.
Options for diagnosing colon cancer can include:-
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Blood tests.
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Stool tests to check for blood.
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X-ray imaging.
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Colonoscopy.
Treatment of colon cancer
Treatment depends on the type and stage of the cancer. The doctor will also consider the patient's age, overall health, and other factors to decide the best available option.
There is no single cure for colon cancer. Treatment options may include surgery, chemotherapy, and radiation therapy. The goal is to remove the cancer, stop it from spreading, and ease any uncomfortable symptoms.
Treatment options for colon cancer include:
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Surgery
Usually the main treatment for early-stage colon cancer is surgery. Some people might only need the cancerous polyp removed. Surgery can also involve removing part or all of the colon. The doctor removes the cancer part and some surrounding areas.
The surgeon may also take out nearby lymph nodes to lower the risk of the cancer spreading to other parts of the body.
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Chemotherapy
During chemotherapy, the healthcare provider gives drugs that mess with cell division by disrupting proteins or DNA to kill cancer cells.
Chemo targets all fast-dividing cells, including healthy ones. Usually, healthy cells can recover from damage caused by chemo, but cancer cells cannot.
A healthcare provider might recommend chemotherapy for colon cancer in various cases, before surgery to shrink the tumor and make it easier to remove, after surgery to kill leftover cells, or if the cancer has spread to other organs.
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Radiation therapy
Radiation therapy kills cancer cells by focusing high-energy gamma rays on them. This treatment destroys cancer cells and can also work well with other treatment options.
Preventing colon cancer
There is no sure way to prevent colon cancer, but some preventive measures may include:-
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Maintaining a healthy weight.
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Regular physical activity.
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Improving a healthy diet.
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Cutting down on saturated fats and red meat.
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Stopping alcohol consumption.
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Quitting smoking.
