According to the Hong Kong Cancer Registry of the Hospital Authority in 2017, colorectal cancer continues to be the commonest cancer with 5,635 new cases, which means that on average, more than 15 people are diagnosed with colorectal cancer every day. Prevention of colorectal cancer mainly depends on a healthy lifestyle and dietary habits, but there is also a more practical method – undergoing early cancer screening such as a colonoscopy.
In fact, colorectal cancer treatment has advanced significantly in recent years. For example, only chemotherapy drugs were available for late-stage colorectal cancer in the past, but the variety of chemotherapy drugs has greatly increased nowadays, such as oral and injectable options, and different combinations to increase effectiveness. For cases that are suitable for targeted therapy, combining chemotherapy with targeted therapy often leads to better results than using chemotherapy drugs alone. There are many cases in clinical practice where patients with late-stage colorectal cancer who use chemotherapy plus targeted therapy can have a longer survival period.
For example, in the past, if colorectal cancer had already spread, it was basically considered incurable. Yet, due to advances in technology and medication nowadays, even if colorectal cancer has spread to the liver or lungs, if the extent is limited to only one lobe of the liver or lung, there is still a chance to remove it through surgery, followed by chemotherapy to cure the disease as much as possible.
Although there have been significant advances in treatment options, early detection is still one of the main factors that affect the cure rate. If it can be detected in stages 1, 2 or 3, the cure rate is certainly higher. Even if it is already in stage 4 (i.e., it has already spread), whether curative surgery is possible depends on whether it is detected in the early stage of stage 4.
Therefore, many countries have been advocating colorectal cancer screening in recent years. The Hong Kong government currently provides faecal occult blood tests for citizens aged 50 and above. If the test result is positive, they will be referred for a colonoscopy. Citizens can also opt for colonoscopy screening.
Colonoscopy can be said to be the top tool for screening colorectal cancer as it helps doctors directly observe the condition of the colon through a camera. This allows for immediate detection of inflammation, polyps (which may develop into colorectal cancer), or cancerous lesions. If there are polyps, they can often be immediately removed to prevent future problems. If there are cancerous lesions, part of the tumor tissue may be removed with the colonoscope for laboratory tests, and then a treatment plan will be formulated. If there are no signs of polyps or cancerous lesions, the participant can repeat the test in 5-10 years.
Currently, colonoscopy is the most accurate diagnostic method for colorectal cancer and the most effective measure in preventing polyps from turning into cancer. Citizens who want to know whether they need screening can consult their doctor for more information.
Dr. Ng Kim Pong
Oncologist experienced specialist doctors