In the Philippines, lung cancer is the second leading cause of cancer deaths among men and women.
Signs and symptoms
Symptoms of lung cancer may vary from one patient to another. The symptoms may depend upon where and how widely extended the tumor is. In some cases, patients do not exhibit any warning signs of lung cancer.
Up to 25% of lung cancer cases are first discovered through a routine chest X-ray or CT scan as a solitary small mass which is sometimes referred to as a coin lesion. On a two-dimensional X-ray or CT scan, the round tumor resembles a coin. Patients with small, solitary masses usually do not report any signs and symptoms at the time lung cancer is revealed.
Common symptoms of primary lung cancers may include cough, coughing up blood], constant chest pain, and shortness of breath.
The following are some conditions that should raise concern for lung cancer:
- A smoker or former smoker who develops a new cough should be concerned about possibility of lung cancer.
- A person who experiences persistent cough that gets worse over time should be seen by a physician or health care provider for evaluation.
- Coughing blood (hemoptysis) can be experienced by some people who have lung cancer. Presence of blood in cough, regardless of amount, should be a cause for concern.
- Some people with lung cancer may experience chest pain. The pain may be characterized as aching and persistent. The pain may lack intensity.
- Shortness of breath due to a blockage to the flow of air in the lung, accumulation of fluid around the lung, or the spread of tumor around the lungs.
- Wheezing, or hoarseness due to inflammation in the lungs.
- Recurring respiratory infections such as bronchitis or pneumonia
About 30%-40% of lung cancer patients exhibit symptoms or signs of metastatic disease. Lung cancer may affect other organs such as the liver, the adrenal glands, the bones, and the brain.
- Metastic lung cancer in the liver does not usually exhibit symptoms, at least until it is discovered.
- Metastic lung cancer in the adrenal glands does not normally show signs or symptoms.
- Metastic lung cancer in the bones causes pain in the backbone (vertebrae), the thighbones, and the ribs.
- Metastic lung cancer in the brain can cause vision problems and difficulties on one side of the body and/or seizures.
A patient with lung cancer may also experience paraneoplastic syndromes which are caused by the chemicals released from the cancers. Such symptoms include the following:
- Extra tissue under the fingernails results to clubbing of fingers.
- Formation of new bone in the area of the lower legs and arms
- Weakness of the muscles
- Skin rashes and degeneration of the brain
- Weight loss and fatigue
Causes and risk factors
- Cigarette smoking – This is the leading risk factor associated with lung cancer. It is estimated that about 90% of lung cancer is associated with tobacco smoking. Smokers are faced with greater risk for lung cancer compared to non-smokers. The risk of developing lung cancer becomes higher with the number of cigarettes consumed and length of smoking period. Physicians refer to the risk in terms of pack-years of smoking. This is computed by multiplying the number of cigarette packs smoked per day by the number of years smoked. This means that the longer an individual smokes and the more packs consumed a day, the greater risk of developing lung cancer. Cigar smoking and pipe smoking can possibly lead to lung cancer just like cigarette smoking. Cigarette lights containing low-tar increases risk of lung cancer as much as regular cigarettes. Cigarettes containing menthol can increase risk even more since they are usually inhaled more deeply by smokers.
- Passive smoking – This is also referred to as second-hand smoke. Breathing the smoke from other smokers can also increase risk of lung cancer. Someone who does not smoke but lives with a smoker is faced with about 20% to 30% greater risk of developing lung cancer. Around 3,000 deaths from lung cancer each year is associated with second-hand smoke.
- Radon – This naturally occurring radioactive gas arises from the breakdown of uranium contained in soil and rocks. Exposure to radon increases an individual’s risk of lung cancer.
- Asbestos – Workers (such as those who work in some mines, mills and textile plants) who are exposed to asbestos are at risk of developing cancer.
- Other cancer-causing agents – Other cancer-causing agents that can increase risk of lung cancer are radioactive ores such as uranium; chemicals or minerals such as arsenic, beryllium, cadmium, silica, vinyl chloride, nickel compounds, chromium compounds, coal products, mustard gas, and chloromethyl ethers; and diesel exhaust.
- Pollution – Particularly air pollutants such as combustion of diesel and other fossil fuels.
Diagnosis and tests
- The health-care provider or physician will ask the patient questions regarding symptoms, medical and surgical history, smoking and work history. The patient will also be asked about lifestyle, general health and medications being taken if any.
- Physical examination
- Getting a chest X-ray is usually the initial step in diagnosing lung cancer. A chest x-ray can be performed unless there is severe hemoptysis. However, a chest x-ray may not always show signs of abnormalities. The presence of abnormalities is not a sure indication of cancer.
- CT (computerized tomography, computerized axial tomography, or CAT) scans may be performed on the patient’s chest, abdomen, and/or brain to find signs of metastatic and lung tumors.
- Low-dose helical CT scan (or spiral CT scan) requires a special type of CT scanner to identify small lung cancers among smokers and former smokers. However, this method is not proven to save lives or lower risk of dying because of lung cancer.
- Magnetic resonance imaging (MRI) scans utilizes magnetism, radio waves, and a computer to produce structure images.
- Positron emission tomography (PET) scanning makes use of short-lived radioactive drugs in order to come up with three-dimensional colored images of those substances found in the body.
- Bone scans are necessary to check if lung cancer has metastasized to the bones.
- Sputum cytology is risk-free and an inexpensive tissue diagnostic procedure.
- Bronchoscopy is a procedure that examines the airways by bronchoscopy in order to reveal areas of tumor that can be sampled for biopsy.
- Needle biopsy uses fine needle to penetrate the skin in order to collect cells for diagnosis from tumor nodules in the lungs.
- Thoracentesis is a method of aspiration to collect sample of fluid in the space between the lungs and chest wall using a thin needle.
- Major surgical procedures can be done to obtain tumor tissue if the methods above do not yield sufficient diagnosis.
- Blood tests alone cannot be used to diagnose lung cancer, however, it may show signs of biochemical or metabolic abnormalities in the body associated with cancer.
Deciding on the appropriate treatment of lung cancer depends on the presence of small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC). Choosing the treatment also relies on the tumor stage, particularly in NSCLC. A patient should have a good general physical condition in order to be able to endure treatment procedures.
The common treatment procedures used for lung cancer are:
- Shortness of breath
- Coughing of blood
- Fluid in the chest (pleural effusion)
- Metastasis - Cancer that spreads to other parts of the body
Prevention and control
- The best thing one can do to prevent lung cancer is to stop smoking. Smokers who are trying to quit smoking can use helpful products such as nicotine gum, nicotine sprays, or nicotine inhalers.
- Avoid exposure to second hand smoke as much as possible.
- Use a home radon test kit to determine possible radon presence and levels in the home.
- Avoid exposure to harmful cancer-causing agents.
- Methods that allow early detection of cancers such as the helical low-dose CT scan can be performed.
Lung cancer is one of the leading causes of cancer deaths in the Philippines. According to the Department of Heath (DOH), an estimated 17,238 new cases of, and 15,881 deaths attributed to lung cancer are expected to happen every year.