Colorectal cancer results from the uncontrollable growth of the cells that line the colon or the rectum. Although many people refer to colorectal cancer as colon cancer, there is only a slight difference. Cancer that affects the colon is colon cancer, and cancer that affects the rectum is rectal cancer. So, colorectal cancer that involves both of those organs is colorectal cancer. 

In most cases, most colorectal cancer cells develop over time from precancerous polyps. Polyps are growths that can change when a series of mutations happen in their cellular DNA. Some of the risk factors of colorectal cancer include inflammatory bowel disease, a family history of colorectal cancer, diet, alcohol intake, and smoking.

You may not notice the symptoms of colorectal cancer until it has advanced, so it is necessary to undergo regular Hong Kong colorectal cancer screening to catch any abnormalities early. 

How does the colon work?

The colon is a part of the human body, basically a long tube that links the small intestines and the rectum. Together with the large intestine, the colon processes and moves digested food across your internal organs, then down to the rectum, where it exits from the body as stool. But the colon has different parts such as:

• Ascending colon where undigested food begins to travel through the colon. It is also where fluids are absorbed more efficiently.
• The transverse colon moves food from one side of the body to the other.
• Descending colon takes over the food after it has been distributed via the transverse colon, and it moves it downwards to the sigmoid column. The sigmoid colon is S-shaped, and it is the final stop before the rectum.
• The rectum joins the colon to the anus and serves as a store for the stool until defecation occurs.

How does colorectal cancer occur?

Usually, your body’s cells develop, divide then die to keep your body functional and healthy. However, this normal process can get out of control whereby the cells grow, continue dividing, and refuse to die. So, colorectal cancer develops when the cells lining the colon and rectum grow and multiply uncontrollably.

As earlier mentioned, in most cases, colorectal cancer starts in the form of tiny precancerous polyps which keep on growing and do not cause any symptoms until they become cancerous. Visiting a Hong Kong colorectal cancer screening facility provides an opportunity for detection and removal of the precancerous polyps before they advance.

There are different types of colorectal polyps, but colorectal cancer emanates from precancerous polyps known as adenomas and sessile serrated lesions. If a polyp is seen during colonoscopy, it can be removed and examined by a pathologist to determine if it is precancerous. If the polyp is precancerous, the doctor can advise you accordingly depending on the type, size, and the number of the precancerous polyps.

Signs of colorectal cancer

One thing to note is that colorectal cancer may be present without experiencing any signs or symptoms, so regular colorectal cancer screening is essential to detect any problems early. Some people are afraid to get screened for cancer because of the devastating effects that may follow. However, you don’t have to worry about anything because the earlier the cancer is detected, the easier it is to treat. Plus, the Hong Kong cancer fund is there to help cancer patients handle the financial burden of cancer treatment.

Common signs of colorectal cancer include:

Blood on the stool- although not in all cases, blood on the stool may be a sign of colorectal cancer, and it is by far the most noticeable. Other conditions that can cause digestive bleeding include hemorrhoids, ulcerative colitis, anal tears, and Crohn’s disease. So when you notice such a sign, you should see a doctor to rule out any serious problem and receive treatment.

• Abdominal or pelvic pain and bloating.
• Change in bowel habits, including diarrhea, vomiting, bowel incontinence, narrowing of stools, and incomplete evacuation.
• Unexplained shortage of red blood cells or anemia. When you are anemic, you feel sluggish, tired, and experience shortness of breath.
• Unexplained weight loss.

It is good to see a doctor for evaluation if you experience these signs. Early diagnosis and treatment can be the only difference in successfully getting rid of the cancerous cells.

When is it appropriate to undergo colorectal cancer screening?

According to experts, people with an average risk of colorectal cancer should start regular screening at 45yrears of age. But if you are at a higher risk or have a family history of developing colorectal cancer, you should begin screening before the age of 45. This is important, especially if you have inflammatory bowel disease. It is also good to consult with your healthcare provider on when to start regular screening based on your risk factors.

What to do if you have a family history of colorectal cancer

It is advisable to get screened for colorectal cancer if you have a family history of colorectal polyps or cancer. Your doctor can determine the appropriate age to start screening depending on your risk factors. This history can be anything from a history of inflammatory bowel disease or cancer of the abdomen.

According to a study, having a first-degree relative with colorectal cancer exposes you two to three times higher than other people without a first-degree relative with colorectal cancer. Around 10-30% of the people who get colorectal cancer have a family history of the disease.

How is it diagnosed?

Colorectal cancer can be diagnosed through various tests, including:

• Imaging tests like CT scan, X-ray, PET scan, MRI scan, angiography, and ultrasound.
• Blood tests including testing liver enzymes, tumor markers, and complete blood count.
• A diagnostic colonoscopy is carried out when you show the symptoms of colorectal cancer.
• Proctoscopy.

After diagnosis, staging occurs, which is the process of identifying the stage of cancer or severity. Treatment of colorectal cancer involves surgery, radiation, or chemotherapy.

The takeaway

The risks of developing colorectal cancer increase as we age, and it is more common in people over the age of 50. But that is not to say younger people cannot develop colorectal cancer. Being overweight, smoking, excess alcohol intake, and not getting enough exercise also increase risks.