What is lung cancer?

Lung cancer is a type of cancer that starts in the lungs. Cancer from the lungs may spread to other areas of the body.¹ When the cancer spreads, it is known as advanced lung cancer or metastasised lung cancer.¹

If you have received a lung cancer diagnosis, you are not alone – lung cancer is one of the most common types of cancer.²

In Singapore, about 5 people are diagnosed with lung cancer every day.² it is the third most common cancer among both men and women in Singapore.^3,4

Types of lung cancer

There are different types of lung cancer, but the two most common types are:^3,5

Who is most at risk of lung cancer?

Other risk factors include:³

• Second hand smoke (passive smoke) is a major risk factor of lung cancer among non-smokers. Passive smoking can increase the risk of developing lung cancer by about 30%.³ No amount of exposure to second-hand smoke is safe
• Age. Lung cancer is more common in people above the age of 40.
• Exposure to cancer-causing chemicals increases the risk of lung cancer, e.g. asbestos, coal gas, chromates, nickel, arsenic, vinyl chloride,mustard gas and radon.
• Air Pollution. Those who live in more polluted cities have a higher risk of lung cancer than those who live in less polluted cities. The World Health Organisation estimates that there are about 4 million excess deaths per year worldwide due to air pollution. One of the largest reasons is due to lung cancer.
• Personal or family history : the risk of lung cancer may be higher if your parents, brothers or sisters, or children have had lung cancer. A lung cancer survivor, especially those who have smoked, may develop another form of lung cancer.

Can lung cancer be prevented?⁸

• Stay away from tobacco. The best way to reduce your risk of lung cancer is not to smoke and to avoid breathing in other people’s smoke.
• Avoid radon exposure. Radon is an important cause of lung cancer. You can reduce your exposure to radon by having your home tested and treated, if needed.
• Avoid or limit exposure to cancer-causing agents. Avoiding exposure to known cancer-causing agents, in the workplace and elsewhere, may also be helpful.
• Eat a healthy diet. A healthy diet with lots of fruits and vegetables may also help reduce your risk of lung cancer. Some evidence suggests that a diet high in fruits and vegetables may help protect both smokers and non-smokers against lung cancer. But any positive effect of fruits and vegetables on lung cancer risk would be much less than the increased risk from smoking.

Who needs to be screened for lung cancer?⁹

If lung cancer is found early, when it is small and before it has spread, it is more likely to be successfully treated.

If you are at high risk of lung cancer (current or former smoker), speak to your doctor about screening for lung cancer.

Usually symptoms of lung cancer do not appear until the disease is already at an advanced stage. Even when lung cancer does cause symptoms, many people may mistake them for other problems, such as an infection or long-term effects from smoking. This may delay the diagnosis.⁶

In recent years, a test known as a low-dose CAT scan or CT scan (LDCT) has been studied in people at a higher risk of getting lung cancer. LDCT scans can help find abnormal areas in the lungs that may be cancer.⁶

How is lung cancer diagnosed?¹⁰

To establish a diagnosis, your doctor will ask about your symptoms and medical history and perform a physical examination. If lung cancer is suspected, you may need imaging tests, such as a chest X-ray or CT scan. A biopsy (taking a small sample of tissue) is usually needed to confirm the diagnosis.

If lung cancer is diagnosed, additional tests may be done to determine whether the cancer is confined to the lung or has spread to other parts of the body. The results help your healthcare team recommend the most appropriate treatment.