What is lung cancer? — Lung cancer happens when normal cells in the lungs change into abnormal cells and grow out of control. There are different types of lung cancer. Some types grow much faster than others do. Lung cancer is the one of biggest cause of deaths from cancer in men and women.
What are the symptoms of lung cancer? — Common symptoms of lung cancer can include: Cough; Trouble breathing, or wheezing; Spitting or coughing up blood; Chest pain that can be dull, sharp, or stabbing; Hoarse voice; Headache and swelling of the face, arms, or neck. If the cancer is growing in the top part of the lungs, it can also cause: Pain in the arm, shoulder, or neck; Droopy eyelid or blurred vision; Weakness of the hand muscles.
All of these symptoms can also be caused by conditions that are not lung cancer. But if you have these symptoms, you should let your doctor know.
What is lung cancer screening? — Lung cancer screening is a way in which doctors check the lungs for early signs of cancer in people who have no symptoms of lung cancer. The goal of lung cancer screening is to find cancer early, before it has a chance to grow, spread, or cause problems. Researchers have been studying chest x-rays and “low dose CT scans” to see if they are good screening tools. (CT stands for “computed tomography.”). A low-dose CT scan uses much less radiation than a normal CT scan and shows a more detailed image of your lungs than a standard x-ray. It turns out that x-rays do not work for screening. Low-dose CT scans, on the other hand, might be helpful screening tools for some people at high risk of lung cancer.
Who should be screened for lung cancer? — For now, experts recommend that people who have smoked heavily for years discuss the pros and cons of screening with their doctor. Then they can decide, with their doctor’s help, if screening is right for them.
The decision to be screened should take these things into account:
- Your general health and level of risk – Your level of risk depends mostly on how much and how long you have smoked, and whether you still smoke.
- The costs involved in screening
- Access to experts in lung cancer screening – Not all doctors are experts at reading low-dose CT scans, or in deciding what to do if a test is abnormal. For screening to be helpful, a very experienced person must read the scan. Plus, it’s important that any abnormal results be managed by a doctor who is an expert at diagnosing lung cancer.
What are the benefits of being screened for lung cancer? — The main benefit of screening is that it helps doctors find cancer early, when it should be easier to treat. This might lower your chances of dying of lung cancer. One large study found that smokers who were screened with low-dose CT scans of the lungs were less likely to die of lung cancer than those who were screened with standard x-ray (low-dose CT scan reduced the risk of death from lung cancer by 20 percent, and the overall risk of death by about 7 percent)
What are the drawbacks to being screened for lung cancer? — The drawbacks include:
- False positives — Low dose CT scans sometimes give “false positives,” meaning they suggest a person might have cancer when he or she does not. This can lead to unneeded worry and to more tests. For example, people who have false positives sometimes have follow-up full-dose CT scans, which expose them to more radiation. They sometimes also need a lung biopsy, which is a procedure to remove a small sample of lung tissue. This procedure can be painful and lead to problems, such as bleeding or a collapsed lung.
- Radiation exposure — Like all x-rays, CT scans expose you to some radiation. Although the radiation dose from the first screening CT scan is low, you would need to have a scan every year, so your exposure would add up. Plus, if you have an abnormal result, you could end up having full dose CT scans.
What if my CT scan is abnormal? — If your scan is abnormal, don't panic. More than 95 out of 100 people with an abnormal scan turn out NOT to have lung cancer. You will need more tests to find out whether you actually have cancer.
How often should I have a low-dose CT scan? — If you and your doctor decide that screening is right for you, you will need to have a low-dose CT scan once a year.
Can lung cancer be prevented? —Cigarette smoking is responsible for almost 90 percent of cases of lung cancer. Exposure to certain substances, such as asbestos, has also been linked to the development of lung cancer. Exposure to second hand smoke and other environmental factors such as radon and asbestos also increase the risk of lung cancer.
The best way to avoid getting lung cancer is not to smoke. Some smokers believe that once they have smoked for a long while, it does little good to quit. However, studies have shown that smokers who quit decrease their risk of lung cancer when compared to those who continue to smoke. Smokers who quit for more than 15 years have an 80 to 90 percent reduction in their risk of lung cancer compared to people who continue to smoke. It does not matter how much or how long you have smoked. Quitting now will reduce your chances not only of lung problems, but also of heart disease and many forms of cancer.
Profile of Associate Professor Dr Ng Teck Han 黄德汉医生 MD (UNIMAS), MRCP (LONDON)
Consultant Physician and Chest Physican 内科与肺科
Dr. Ng Teck Han has special interest and subspecialised in Respiratory Medicine; and in 2006 has been training under Prof Dr. Fauzi B Abdul Rani and Associate Prof Dr. How Soon Hin on specialize complex respiratory procedures. He has received various respiratory medicine training in Malaysia, Singapore and Japan. He used to work in International Islamic University Malaysia as an Associate Professor and lecturer for 4 years as well as invited adjunct lecturer for University Science Islam Malaysia. He is now a lecturer in Faculty of Medicine, Universiti Tunku Abdul Rahman (UTAR).