Lung cancer is also called cancer of the bronchus. In Hong Kong, it is the most common cancer in men and the third most common cancer in women. In 2009, there are 4,365 new cases of lung cancer in Hong Kong, accounting for 16.8% of total cancer new cases. It is also the top killer cancer in both men and women, causing  3,700 deaths every year in this city. 

Smoking is by far the most important cause of lung cancer since 90% of lung cancers are related to smoking. However, never smoker can also develop lung cancer.

Lung cancer is largely a preventable disease. The risk of developing lung cancer falls quite quickly if you stop smoking,. After about 15 years, the chance of developing the disease is similar to that of a non-smoker.

There are two main types of primary lung cancer, small cell lung cancer and non-small cell lung cancer. About 15% lung cancers are small cell; the rest are non-small cell.

The two main types are treated quite differently. Chemotherapy and radiotherapy are usually used for small cell lung cancer. Depending on the disease stage, surgery, chemotherapy, radiotherapy and targeted therapy may be used for non-small cell lung cancer. Unfortunately, only a small percentage of patients can be offered curative surgery. In some selected cases, high dose radiotherapy may have similar efficacy as surgery. With the recognition of different molecular subtypes of non-small cell carcinoma, targeted therapeutic drugs are increasingly used. 

Signs and symptoms of lung cancer include:

Persistent cough,

Shortness of breath,

Blood-stained sputum,

Chest discomfort,

Loss of appetite and weight loss,

Diseases spreading outside lung may cause enlarged neck nodes, bone pain etc.

If you have any of the above symptoms, it's important to have them checked by your family physician.

Suggested further reading: CancerHelp UK - Lung cancer