Madam Christine Chen* started coughing on and off for four weeks, and was initially given antibiotics by her doctor to treat what he suspected was a lung infection. However, despite taking the antibiotics, she continued to cough, and in fact started feeling slight breathlessness when walking or exercising.

She had no reason to suspect she had lung cancer. After all, the 45-year-old was medically fit and had no family history of cancer. She worked in a primary school, never smoked, and neither did anyone in her family, so she had no exposure to second-hand smoke either.

Mdm Chen went back to her doctor​ and underwent a chest X-ray which showed multiple spots in both lungs. Subsequently, a CT scan was done at a hospital and it picked up not only bilateral lung masses but also enlarged lymph nodes and fluid in her lungs. A bronchoscopy and lung biopsy confirmed that she had Stage 4 lung cancer and that the cancer had spread to both lungs, the lining (pleura) of her lungs, and her lymph nodes.

Lung cancer: women are more at risk

Mdm Chen is not the only patient who has never smoked, yet has fallen prey to lung cancer. These “never-smokers” – as they are referred to in the medical field – are being hit by the disease, and hit hard too.

A study by the National Cancer Centre Singapore (NCCS) found that three in 10 lung cancer patients here are never-smokers and the incidence is rising, said Dr Ang Mei Kim, Senior Consultant from the Division of Medical Oncology​ at National Cancer Centre Singapore (NCCS), a member of the SingHealth group.

More than half the never-smokers seen at NCCS are usually diagnosed with advanced stage (Stage 3 or 4) lung cancer. “There are few tell-tale signs. It sneaks up on them to deal a heavy blow. Usual symptoms at the time of the lung cancer diagnosis are cough, blood in the phlegm, chest pain, breathlessness and weight loss,” said Dr Ang. She said women seem more vulnerable than men, as 70 per cent of never-smokers with lung cancer here are women.

The statistic is even more glaring when compared globally, where it appears that Asian female non-smokers are more vulnerable to lung cancer than their Western counterparts.

“Less than 4 per cent of Chinese women in Singapore smoke, yet, Singapore has a higher lung cancer rate among women (21.3 cases per 100,000 females) compared to other countries like Germany and Italy, where one in five women smoke,” said Dr Ang.

Risk factors of lung cancer

Exposure to second-hand smoke at home or at the workplace – one of the main causes of lung cancer in never-smokers increases the risk by 25 per cent.

Another risk factor is environmental pollutants, particularly radon. Studies in Chinese populations show that burning coal and biomass, particularly in poorly ventilated areas for cooking and heating, may also increase the risk.

“A large proportion of lung cancers in never-smokers cannot definitely be associated with any established environmental risk factor. It is also thought that certain genes, or changes that occur in the genes, may affect a person’s susceptibility to these carcinogens and to developing lung cancer. This is an area of current intense research,” said Dr Ang.

*Patient description is based on a typic​al patient profile.

Read on for treatment options for lung cancer.

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