Most Lung Cancer Patients Are Diagnosed at an Advanced Stage: How Precision Medicine Is Changing Treatment

Lung cancer treatment has entered the era of precision medicine. Advances in genetic testing, targeted therapy and immunotherapy now allow doctors to tailor treatment according to each patient's individual characteristics. This offers patients diagnosed at an early stage a greater chance of cure, while enabling those with advanced disease to manage their condition more effectively.

In the past, lung cancer was commonly associated with long-term smokers. However, in recent years, an increasing number of women who have never smoked, as well as younger individuals, have been diagnosed with the disease, challenging the traditional perception of lung cancer.

According to Dr Winnie Ng Nyek Ping, Consultant Clinical Oncologist at Subang Jaya Medical Centre (SJMC), lung cancer remains one of the leading causes of cancer-related deaths in Malaysia. As early-stage lung cancer often presents with few or no obvious symptoms, most patients are diagnosed at Stage III or Stage IV, by which time the optimal window for treatment may have been missed.

She also emphasised that lung cancer is not exclusive to smokers. Non-smokers are also at risk of developing the disease. Lung cancer is broadly classified into two main types: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). NSCLC accounts for approximately 70% to 80% of all lung cancer cases and can be further categorised into adenocarcinoma, squamous cell carcinoma, large cell carcinoma and others.

"Adenocarcinoma is the most common subtype, accounting for more than half of all NSCLC cases, and is more frequently seen in women who have never smoked. Squamous cell carcinoma, on the other hand, is more commonly associated with smoking."

Dr Ng explained that conventional chest X-rays often fail to detect small lung nodules at an early stage. Therefore, in accordance with international guidelines, she recommends low-dose computed tomography (LDCT) screening for high-risk individuals, including long-term smokers aged 50 years and above, individuals who have quit smoking within the past 15 years, and those who meet the recommended smoking-exposure criteria. LDCT significantly improves the likelihood of detecting lung cancer at an earlier stage.

She added that, at present, there is no reliable blood test that can replace LDCT. Although multi-cancer early detection (MCED) blood tests have high accuracy, they are not sufficiently reliable to be used as a standalone screening tool.

Although early-stage lung cancer often has no obvious symptoms, Dr Ng advised members of the public to seek medical attention promptly if they experience a persistent cough, shortness of breath, recurrent lung infections, coughing up blood, unexplained weight loss or reduced appetite. While these symptoms may be caused by conditions such as tuberculosis or other infections rather than lung cancer, they should still be evaluated by a specialist.

Dr Winnie Ng pointed out that modern medical treatment for lung cancer from Stage I to Stage III aims for a cure.

Treatment for Stages I to III Aims for a Cure

Dr Ng explained that lung cancer is staged using the internationally recognised TNM classification system, which assesses tumour size (T), the extent of lymph node involvement (N), and whether the cancer has spread to distant organs (M). Treatment is then tailored according to the stage of the disease.

She emphasised that for Stage I to Stage III lung cancer, the primary treatment goal is curative. “Patients with Stage I disease can usually be cured through surgical removal of the tumour or stereotactic body radiotherapy (SBRT).”

For Stage II and Stage III disease, the primary aim of treatment remains curative. This involves a multimodality approach tailored to the individual patient based on tumour location, size and the overall extent of disease.

“Consequently, treatment options vary and may include surgery, chemoradiotherapy, or chemo-immunotherapy administered before and after surgery. Additionally, personalised targeted therapy (based on NGS) may be given following the completion of surgery or definitive chemoradiotherapy (CRT) to achieve longer disease control.”

Precision Medicine Is Central to Stage IV Treatment

Dr Ng explained that although Stage IV lung cancer has spread to other organs and is generally not curable, modern treatment no longer relies on a single therapy. Instead, it focuses on personalised care guided by genetic molecular markers identified through upfront biomarker testing or next-generation sequencing (NGS), which also helps determine the most appropriate treatment strategy and assess whether a tumour is operable or inoperable.

SJMC introduced next-generation sequencing (NGS) for cancer mutation profiling in 2018, equipping clinicians with comprehensive genomic insights to develop more precise, personalised treatment strategies and further advancing precision medicine.

"Doctors first perform NGS to identify genetic alterations in the cancer cells and determine whether targeted therapy is appropriate. Biomarker testing is also carried out to assess whether a patient is suitable for immunotherapy. These treatments may be combined with chemotherapy and other therapies to achieve long-term disease control, with the goals of prolonging survival and maintaining quality of life."

She noted that the average survival of patients with Stage IV lung cancer has increased from approximately six months to one year in the past to two to five years or longer today.

Dr Ng also addressed common concerns surrounding chemotherapy. She explained that advances in anti-nausea medications and supportive care have substantially reduced the side effects associated with modern chemotherapy, allowing most patients to complete their treatment successfully.

She further stressed that palliative care should not be regarded as giving up on treatment. Instead, it should be introduced early to provide pain management, symptom control and psychological support, helping patients complete their treatment while improving their quality of life.

"Studies have shown that patients who receive palliative care earlier may actually have longer survival."

Following treatment, Dr Ng advised patients to maintain a balanced diet with adequate protein intake, attend regular follow-up appointments and undergo scheduled radiological scans. She noted that the first three years after treatment represent the period with the highest risk of recurrence and therefore require close monitoring.

Future Treatments Will Become Even More Precise

Dr Ng said that precision medicine has already transformed lung cancer treatment. Patients diagnosed at an early stage now have a greater opportunity for cure and a lower risk of recurrence, while even those with Stage IV disease may be able to achieve long-term disease control and maintain a better quality of life through precision treatment.

Looking ahead, she believes lung cancer treatment will become increasingly precise and personalised.

"In addition to existing immunotherapy, antibody-drug conjugates (ADCs), bispecific antibodies and cancer vaccines are among the key areas of ongoing research. ADCs combine antibodies with anti-cancer drugs to deliver treatment more precisely to cancer cells. While this approach is still undergoing clinical research in lung cancer, it has shown promising potential. Cancer vaccines, meanwhile, aim to activate the immune system to recognise and attack cancer cells."

“Liquid biopsy is another emerging technology that detects circulating tumour DNA (ctDNA) in the bloodstream. It may help monitor changes in the cancer, evaluate treatment response and assess the risk of recurrence.”

Dr Ng reiterated that early detection and timely treatment remain the cornerstones of lung cancer management. The public should undergo regular health check-ups, while individuals at high risk should receive LDCT screening in accordance with established guidelines. Anyone experiencing persistent symptoms should seek medical attention promptly. In addition, avoiding smoking and minimising exposure to second-hand smoke remain important measures for reducing the risk of lung cancer.

To learn more about precision medicine for cancer at Subang Jaya Medical Centre, visit: https://subangjayamedicalcentre.com/our-specialties/oncology-malaysia

Source: Sin Chew Daily