Lung cancer is the most common and deadly form of cancer. It is responsible for more deaths by cancer than any other type worldwide. There are two major type of lung cancer: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). NSCLC constitutes about 85% of all lung cancers while SCLC is a more aggressive form that tends to spread faster.
The main risk factor – for about 85 per cent of cases – is smoking. Cigarette smoke contains carcinogens, meaning chemicals that can cause cancer, and which injure lung cells to make them more likely to mutate into cancers. But some non-smokers also get lung cancer, perhaps from a different risk factor such as secondhand smoke, air pollution, radon gas, asbestos or a family history of the disease.
Lung cancer often presents without symptoms until it has progressed, which is why early detection can be difficult. Common symptoms include a cough that lasts for more than three weeks, coughing up blood, chest pain, shortness of breath and unexplained weight loss. Since these symptoms can be misattributed to other issues such as a cold, they need to be evaluated by a healthcare provider if they persist.
Lung cancer is typically diagnosed on imaging tests such as an X-ray or CT scan, which can show up an unusual lump in the lungs, and confirmed by a biopsy. If lung cancer is caught early – and particularly if detected by low-dose CT screening in high-risk people – there is a much better chance of curing it.
Treatment options for lung cancer depend on the stage and type of cancer. For early-stage cancer, surgery may be used to remove the tumour and some surrounding tissue. For more advanced stages, treatment may include radiation therapy, chemotherapy and newer targeted therapies that attack from inside the cancer cells. Immunotherapy, one of the newest types of treatment, works with a patient’s immune system antibodies and cells to attack and destroy cancer cells. For certain types of lung cancer, immunotherapy has shown that it can extend people’s lives.
Prevention, however, remains a keystone in the battle against lung cancer. There is nothing more effective than quitting or avoiding smoking (or tobacco smoke). Screenings are also recommended for people known to be at high risk for the disease, such as smokers or those with a significant exposure to risk factors.
