Colorectal cancer is the second most common cancer in Hong Kong. According to a recent study by the Chinese University of Hong Kong, there is a trend of young adults are being diagnosed with colorectal cancer worldwide, and the number of cases has been continuously increasing over the past two decades. It is crucial to analyse the formation, survival rate, symptoms, and prevention methods of colorectal cancer for our health.

Association Between Colorectal Cancer and the Development of Polyps  

Polyps are abnormal growths of the inner lining of the colon, and they can be either benign or potentially become malignant tumors over time. These malignant tumors have the potential to spread to other parts of the body through the bloodstream and lymphatic system, further leading to the development of metastatic colorectal cancer.

The formation of polyps occurs when there is abnormal cell proliferation within the colon, where these cells do not undergo normal cell death at the appropriate point in their life cycle. These cellular abnormalities may be caused by genetic mutations, which can be either inherited or may occur due to certain factors in an individual's lifestyle.

Timely detection: Achieving a five-year survival rate of over 90%

According to research from the LKS Faculty of Medicine, the University of Hong Kong (HKUMed), the five-year survival rate for stage I colorectal cancer can be as high as 90% or more. This means that there is a high chance of survival within five years after diagnosis. In contrast, the five-year survival rate for stage IV colorectal cancer is only 8%.

Even though not every colon polyp progresses to colorectal cancer, over 90% of colorectal cancers originate from polyps. This transformation process may take five to ten years.

Symptoms of colorectal cancer

Early-stage colorectal cancer often does not have obvious symptoms, making it easy to overlook. However, as the tumor grows, the following symptoms may appear:

• Change in bowel habits, such as diarrhea or constipation

• Blood in the stool or black stools

• Feeling that bowel does not empty completely

• Abdominal bloating or pain

• Anemia and unexplained weight loss

• Fatigue

How to prevent colorectal cancer?

Maintaining healthy lifestyle habits and dietary choices can effectively prevent or reduce the risk of colorectal cancer. By making some small and manageable changes, you can achieve this goal.

• Maintain a healthy weight: Being overweight or obese increases the risk of colorectal cancer. Maintain an ideal healthy weight, engage in regular physical activity, and follow a balanced diet rich in fruits, vegetables, whole grains, and low-fat options.

• Healthy diet: Consuming a diet rich in vegetables and fruits can reduce the risk of many cancers. Reduce consumption of red meat, processed meats, saturated fats, and refined carbohydrates to help lower the risk of colorectal cancer. Include whole grains, legumes, nuts, and seeds in your diet and limit the intake of processed and fried foods.

• Regular exercise: Engaging in regular physical activity such as walking, jogging, swimming, or cycling helps lower the risk of colorectal cancer. Aim for at least 150 minutes of moderate-intensity aerobic activity or 75 minutes of vigorous-intensity aerobic activity per week.

• Avoid alcohol consumption: Alcohol has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC) and is associated with an increased risk of various cancers, including colorectal cancer.

• Avoid smoking: Smoking not only increases the risk of lung cancer but has also been proven to cause various other cancers such as oral, throat, tongue, esophageal, stomach, bladder, and kidney cancers.

• Regular screening: Undergo regular screenings such as colonoscopy, fecal occult blood tests, or genetic testing to aid in the early detection of colorectal cancer or its precancerous conditions. Discuss with your doctor when and how often to undergo screenings based on your age, family history, and other risk factors.

• Know your family history: If there is a history of colorectal cancer or hereditary conditions such as familial adenomatous polyposis (FAP) or hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome, in your family, consult with a doctor to determine if genetic testing or colonoscopy is necessary.

• Manage chronic conditions: If you have inflammatory bowel diseases such as ulcerative colitis or Crohn's disease, work with your doctor to effectively manage the condition and reduce the risk of colorectal cancer.

Therefore, early detection and screening for colorectal polyps are crucial to identify potential colorectal cancer. If you have any concerns or questions, it is suggested to seek advice and assistance from healthcare professionals. Early detection and treatment of colorectal cancer not only provide an opportunity for early intervention but also significantly improve survival rates and enhance the quality of life for patients after treatment.