How serious is lung cancer as a health problem?

Lung cancer is the most common cause of cancer deaths around the world. About 1,500 people in Singapore were diagnosed with lung cancer in 2008. In that same year, more than 160,000 people were estimated to have died from the disease in the United States alone.

How do you define "advanced lung cancer"?

Lung cancer can be divided into Small Cell Lung Cancer (SCLC), which accounts for less than 15% of lung cancers, and Non-Small Cell Lung Cancer (NSCLC), which comprises more than 80% of lung cancers.

Patients who are diagnosed with advanced NSCLC have either Stage III or Stage IV of the disease and their chances of survival are very poor. Only about 8.4% of patients of Stage III patients and less than 1.6% of patients in Stage IV are expected to survive for more than five years.

Those with advanced SCLC are divided into limited and extensive stages. Less than 1% of those in the latter stage are expected to live beyond five years.

What are the standard methods of treating advanced lung cancer?

Chemotherapy, combined with occasional radiation if the patient is physically fit, is the usual course of treatment for advanced lung cancer.

However, studies have shown that such standard anti-cancer drug treatment - or what we call cytotoxic chemotherapy - while useful in some ways, is still insufficient in helping to boost a patient's chances of beating the odds. The five-year overall survival rate based on such a treatment remains dismal, hence the need for us to turn to new therapies that have proven to be more effective.

What does a personalised approach to cancer treatment mean?

This means tailoring a patient's treatment according to the biological make-up of the tumour as well as certain features of the patient.

As such, several factors - his race, gender, smoking history, the type of lung cancer and whether there are mutations of the epidermal growth factor receptor (EGFR) gene in the cancer cells - will be taken into account before the oncologist decides what the best course of treatment for the patient is.

Studies have shown that personalised medicine have not only produced better results but also improved the patients' quality of life.

Examples of personalised medicine

Some advanced lung cancer patients may respond better when anti-angiogenic drugs such as bevacizumab - which kills cancer cells by starving them of their blood supply - are added to the chemotherapy process.

Others, such as extensive stage SCLC patients, may be responsive to drugs such as cisplatin and etoposide, coupled with radiation therapy.

If there is EGFR gene mutation in the cancer cells, drugs such as gefitinib or erlotinib can be used to kill the cancer cells in the lungs.

Recently, it was found that Asian patients who were non-smokers or were light smokers could be treated with gefitinib without having to undergo chemotherapy.