Lung cancer unmasked: Not just a smoker’s disease
An oncologist discusses myths and risk factors, screening methods for high-risk groups as well as treatment options for Singapore’s third-most prevalent cancer.

Dr Patricia Kho, senior consultant and medical director at Icon Cancer Centre at Mount Alvernia, urges lung cancer patients to stay hopeful as new treatments may enable normal lives. Photos: Icon Cancer Centre, Shutterstock
This audio is generated by an AI tool.
Lung cancer, ranked as the third-most common cancer among men and women in Singapore, is also the leading cause of cancer-related deaths among males in the country. Despite its prevalence, it remains one of the most misunderstood and underestimated diseases. For example, lung cancer is often believed to be a “smoker’s disease”, yet non-smokers are not immune.
Lung cancer occurs when abnormal cells in the tissue of one or both lungs grow in an uncontrolled manner. There are two main types of lung cancer: Small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). NSCLC accounts for approximately 87.3 per cent of all lung cancer cases locally and is further classified into subtypes based on cell type and mutations.
FACTORS CONTRIBUTING TO LUNG CANCER RISK

While smoking remains one of the primary risk factors for lung cancer, a local study done in 2018 found that 48 per cent of lung cancer patients were never-smokers – individuals who have never smoked or smoked fewer than 100 cigarettes in their lifetime.
Dr Patricia Kho, senior consultant and medical director at Icon Cancer Centre at Mount Alvernia, pointed out that inhaling second-hand smoke is just as harmful as smoking. Furthermore, the World Health Organization reports that second-hand smoke contains around 60 cancer-causing chemicals while other studies estimate that passive smoking raises lung cancer risk by about 25 per cent.
Dr Kho highlighted that the Asian population has a higher proportion of never-smokers compared to the Caucasian population, yet the former group experiences a higher incidence of lung cancer. Among these patients, NSCLC is often diagnosed, characterised by the presence of epidermal growth factor receptor (EGFR) mutation. “EGFR is a protein found on the surface of certain cells that regulates cell division and survival. An EGFR mutation can cause these proteins to grow abnormally, leading to the rapid division of cancer cells,” said Dr Kho.
WHEN TO SEEK MEDICAL ATTENTION

Lung cancer, especially in its early stages, may not cause symptoms. Many common issues, such as a cough that does not go away, can be attributed to other medical conditions. However, it’s important not to dismiss a chronic cough as a mere lingering effect of a past infection.
If you experience persistent coughing for weeks, Dr Kho recommends seeking medical attention. “It’s better to be safe than sorry. If deemed necessary, your general practitioner (GP) may arrange for a chest X-ray,” she said, adding that if a lung mass is detected, the GP is likely to refer the patient for further scans or to a lung specialist for thorough evaluation.
Other symptoms of lung cancer may include blood-stained sputum, shortness of breath, recurring chest infections, fatigue, vocal hoarseness and involuntary weight loss. In some cases, individuals may experience shoulder tip pain and facial swelling, or chest pain that worsens with breathing. Dr Kho urges anyone experiencing these symptoms to seek prompt medical consultation.
Currently, there is no validated lung screening test included in standard health screening packages offered locally. However, individuals in the high-risk category or with a first-degree family history of lung cancer should consider consulting their doctor about the suitability of lung cancer screening.
High-risk groups include those aged 50 and above, current smokers or those who have quit within the last 15 years, and those with a smoking history of 20 pack-years or more. For such individuals, an annual low-dose CT scan of the lungs is recommended. If abnormalities are detected during the scan, the patient may be referred for a lung biopsy, a procedure where small samples of lung tissue are removed with a special biopsy needle or with surgery. This step is crucial for the diagnosis of lung cancer, said Dr Kho. Understanding these targeted screening methods allows high-risk individuals to take proactive steps towards safeguarding their health.
NAVIGATING THE TREATMENT JOURNEY

Lung cancer treatment plans vary due to the different subtypes of the disease. Other factors, such as cancer stage, patient medical history, age and fitness level, are taken into consideration, too. Recognising the uniqueness of each patient, Dr Kho believes that optimal cancer care should encompass a customised, evidence-based treatment approach. She also underscored the importance of a multidisciplinary team dedicated to supporting the patient throughout their cancer journey.
Despite being among the most common cancers in Singapore, data from the 2021 Singapore Cancer Registry shows that lung cancer survival rates have improved significantly, thanks to a more comprehensive understanding of the disease and the availability of advanced treatment options.
When identified in its early stages, lung cancer can often be treated effectively. “In later stages, while the survival rate may be lower, we can now extend the period of cancer control due to improvements in treatments. The goal is to enable the patient to remain active and continue leading a normal life,” said Dr Kho.
She shared that there are now more than 20 drugs available for treating lung cancer. According to Dr Kho, newer treatments such as immunotherapy and targeted therapy have shown improved outcomes. Oral targeted therapy and immunotherapy, which can be used alone or with chemotherapy, typically result in better response and survival rates.
Enhancements in surgical techniques have also reduced the extent of lung tissue removal necessary for intervention, allowing for better patient recovery. Urging individuals diagnosed with lung cancer to remain optimistic, Dr Kho said: “New treatment pathways have emerged, with more on the horizon. Many of these options have enabled patients to lead normal lives, so don’t delay in seeking medical attention.”
Learn more about the services offered at Icon Cancer Centre.