Colon cancer, also called colorectal cancer, is one of the most common cancers around the world.
It begins in the colon or rectum, which are parts of the large intestine. The large intestine is the final part of the digestive system.
It absorbs water from food waste and helps remove waste from the body. Colon cancer usually starts as small growths called polyps. Most polyps are harmless at first, but some can slowly turn into cancer over many years if they are not removed.
One reason colon cancer is so dangerous is that it often develops quietly. In the early stages, many people feel completely healthy and notice no obvious problems. By the time symptoms appear, the cancer may have already grown or spread.
The good news is that colon cancer is one of the most preventable cancers because doctors can often find and remove polyps before they become cancer. Early treatment also gives people a much better chance of making a full recovery.
Doctors recommend regular screening for many adults, especially those aged 45 and older. People with a family history of colon cancer or certain bowel diseases may need to begin screening even earlier. Screening tests can find hidden signs of cancer before symptoms appear, making them one of the best ways to protect your health.
Even though early colon cancer often causes no symptoms, there are several warning signs that should never be ignored. One of the most common is a lasting change in bowel habits. This may include diarrhea, constipation, or stools that look different from normal.
Some people feel that they still need to use the toilet even after they have had a bowel movement. These changes can happen for many reasons, such as diet or stress, but if they continue for more than a few days or keep returning, they should be checked by a doctor.
Another important warning sign is blood in the stool. The blood may be bright red, dark red, or make the stool look black. Sometimes the amount of blood is so small that it cannot be seen without a laboratory test.
Any unexplained bleeding from the digestive system should always be taken seriously because it can be caused by colon cancer or another medical condition that needs treatment.
Losing weight without trying is another symptom that should not be ignored. Cancer can change the way the body uses energy and nutrients. If you notice steady weight loss without changing your diet or exercise habits, especially together with bowel problems, it is important to seek medical advice.
Feeling tired all the time can also be an early sign. Colon cancer may cause slow bleeding inside the bowel over many weeks or months. This blood loss can lead to anemia, a condition in which the body does not have enough healthy red blood cells to carry oxygen. People with anemia often feel weak, tired, dizzy, or short of breath even after getting enough rest.
Some people also develop stomach pain, cramping, bloating, or a feeling of fullness after eating only a small amount of food. These symptoms may come and go at first but can gradually become more frequent. While these problems are often caused by less serious conditions, they should not be ignored if they continue.
Research supports the importance of paying attention to these early symptoms. A study published in the journal BMJ Open found that many people with early-stage colon cancer experienced rectal bleeding and changes in bowel habits months before they were diagnosed.
Another study published in Cancer Epidemiology reported that many patients waited too long before seeing a doctor, which meant their cancer was discovered at a later stage when treatment was more difficult.
Several screening tests are available. Stool tests can detect hidden blood or abnormal DNA linked to cancer. A colonoscopy allows a doctor to examine the entire colon with a small camera and remove suspicious polyps during the same procedure. Flexible sigmoidoscopy is another test that examines the lower part of the large intestine.
Although having one or more of these symptoms does not automatically mean you have colon cancer, it is always better to have persistent symptoms checked early. Prompt medical attention can find many conditions before they become serious.
The research published in BMJ Open and Cancer Epidemiology highlights an important message: recognizing early warning signs and taking part in regular screening can save lives.
If you notice ongoing changes in your bowel habits, blood in your stool, unexplained weight loss, unusual tiredness, or persistent stomach pain, speak with your healthcare provider. Early diagnosis offers the best chance of successful treatment and long-term health.
If you care about cancer, please read studies that a low-carb diet could increase overall cancer risk, and berry that can prevent cancer, diabetes, and obesity.
For more health information, please see recent studies about how drinking milk affects the risks of heart disease and cancer and results showing vitamin D supplements could strongly reduce cancer death.
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