Lung cancer is one of the top three most common cancers in Hong Kong with a very high death rate. Early lung cancer has no obvious symptoms so many cases are diagnosed at advanced stages. Treatments become more difficult when the cancer has metastasized.
Causes of lung cancer are not entirely clear, but known risk factors include:
- Long-term smoking (many lung cancer patients are smokers) or long-term exposure to secondhand smoke
- Age: risk of lung cancer increases with age
- Exposure to carcinogens, such as asbestos
- Air pollution
- History of chronic lung disease
Early lung cancer has no obvious symptoms, though some of them are similar to those of other lung diseases. However, the following symptoms may be signs of lung cancer, so medical examinations should be arranged as soon as possible if you are concerned about symptoms such as:
- Persistent cough
- Weight loss and loss of appetite
- Undue fatigue
- Shortness of breath
- Blood-stained sputum
- Chest pain, especially when coughing or deep breathing
However, these symptoms are not unique to liver cancer. If the above symptoms appear, there is no need to worry too much but medical attention should be sought as soon as possible so that any necessary diagnostic procedures and treatments may be started early to prevent disease progression.
Screening and Diagnosis
Initial examinations for lung cancer include:
- Chest X-ray
- Sputum cytology test
- Low-dose computed tomography (CT) scan of the lungs
If lung cancer is diagnosed, further examinations will be performed to determine the stage or the degree of metastasis of the cancer. These examinations include:
- tic resonance imaging (MRI) of the brain
- Positron emission tomography (PET)
- Radioisotope bone scan
Treatment for liver cancer depends on the patient’s condition, which is determined based on the type, size, location, and degree of metastasis of the tumour, as well as the patient’s age and physical condition.
Surgery is the ideal treatment for early-stage lung cancers, and aims to remove the tumour(s) and part of or the entire lobe of the lung. In the past, open surgery (i.e. the traditional method) was the surgical method of choice, but recent years minimally invasive procedures have become very popular.
Chemotherapy is treatment with drugs to destroy cancer cells in an effort to shrink the tumour or control the growth of cancer. Chemotherapy may be administered as a systemic therapy (circulates throughout the body) or a topical therapy (applied to the skin).
Radiation Therapy and Chemotherapy
For patients in the middle or late stages of lung cancer who are not suitable for surgery, radiation therapy and chemotherapy are often given together to control the disease.
Chemotherapy is treatment with drugs to destroy cancer cells in an effort to shrink the tumours or control their growth. Radiation therapy is the use of high-energy radiation to kill cancer cells. New systems such as Tomotherapy, a high-speed helical radiation system, direct radiation energy at the tumours, minimizing exposure of energy to normal cells and reducing the development of possible side effects.
Targeted therapy employs molecular biology techniques that focus on the mechanisms by which cancer cells mutate, proliferate, and spread in an effort to inhibit their ability to grow and repair. However, this type of treatment is not suitable for all lung cancer patients.