Lung cancer is cancer of some of the cells in part of your lung, usually beginning in the lining of the airway. A cancer that arises in cells lining an organ is called a carcinoma.
There are different types of lung cancer. Lung cancers are classified according to the type of cell affected. There are two main types: small cell carcinomas and non-small cell carcinomas. Small cell carcinomas
Small cell carcinomas, also called oat cell carcinomas because of the cell shape, account for around 15 per cent of lung cancers. This type of lung cancer is strongly associated with cigarette smoking. Unfortunately, it spread early and causes few initial symptoms, with the result that more often than not it has already metastasised at the time of diagnosis. Non-small cell carcinomas
Non-small cell carcinomas include squamous cell carcinoma, adenocarcinoma, large cell carcinoma, bronchiolo-alveolar cell carcinoma and mesothelioma.
These carcinomas affect the cells that line the main bronchi. As these tumours enlarge they can spread into the chest wall and local lymph nodes. Squamous cell carcinoma has a lower rate of metastasis (spread to other parts of the body) than other types of lung cancer and is generally discovered earlier, resulting in the best prognosis following treatment.
Mesothelioma is not, strictly speaking, a lung cancer. It is a rare cancer of the pleural membranes on the surface of the lungs and is strongly related to asbestos exposure. Causes of lung cancer
As with many cancers, we do not know the cause in all cases. Cigarette smoking is the major cause of lung cancer but it is not known why one smoker develops lung cancer and another does not. Up to 90 per cent of lung cancer is caused by smoking. Lung cancer occurs most often in adults between the ages of 40 and 70 who have smoked cigarettes for at least 20 years. They are also likely to have started smoking as teenagers.
There is also increasing evidence to suggest that environmental tobacco smoking (passive smoking) can bring about disease in adults, children and infants.
Occupational exposure to asbestos is associated with an increased risk of asbestosis and mesothelioma. There is a doubling of risk for people with asbestosis to develop a lung cancer, and if the person also smokes then the risk is multiplied. Other occupational exposures that possibly are associated with lung cancer include contact with the processing of steel, nickel, chrome and coal gas. Exposure to radiation causes an increased risk of all cancers, including lung cancer. Miners of uranium, fluorspar and haematite may be exposed to radiation by breathing air contaminated with radon gas.
How common is lung cancer?
Around 3500 check number Malaysians are diagnosed with lung cancer each year. Lung cancer is the most common cause of death from cancer in Malaysian men, and the third most common for women. Diagnosis Some people have no symptoms, but learn that they have lung cancer when a tumour shows on a routine chest x-ray. Others realise that something is wrong when respiratory symptoms get worse or a bout of bronchitis fails to get better quickly. Some symptoms are common to other disorders, but a doctor should check them. The most common symptom of lung cancer is a persistent cough or change in a chronic cough. Shortness of breath, bloodstained sputum, chest pains and repeated bouts of pneumonia or bronchitis may also be signs of lung cancer. In the later stages of lung cancer, people may experience fatigue, loss of weight, extreme shortness of breath, hoarseness, difficulty in swallowing and a buildup of fluid in the chest cavity. There may also be symptoms that seen unrelated to the lungs. These may be caused by the spread of a lung cancer to other parts of the body. What doctors and other health professionals will I see? Your general practitioner will refer you for initial tests to confirm whether or not you have cancer. This can be a worrying and tiring time, especially if you need to have several tests. If a diagnosis of cancer is made, he or she will also refer you to a specialist who will advise you about treatment options. You should expect to be cared for by a cooperative team of health professionals from all major disciplines, in a treatment centre that has available all means of diagnosis and treatment. Specialists and other health professionals who care for people with lung cancer include: Respiratory physicians: usually responsible for investigating the symptoms, making a diagnosis and staging the disease Thoracic (chest) surgeons: responsible for some biopsies and removing tumours if they can be operated upon Medical oncologists: responsible for chemotherapy Radiation oncologists: responsible for radiotherapy Dieticians: recommend the best diets to follow while you are in treatment and recovery Nurses: assist you through all stages of your hospitalisation and cancer experience Social workers, physiotherapists and occupational therapists: advise you on support services and help you to get back to normal activities. How lung cancer is diagnosed
If lung cancer is suspected, several tests can be used to see whether or not it is present. The doctor will first ask you about your past and current health, smoking and work history, and do a physical examination. Then, he or she may recommend that you have a test or a series of tests for lung cancer. These tests can include a chest x-ray, one or more biopsies and one or more scans. Biopsy procedures for lung cancer include sputum cytology, bronchoscopy, fine needle aspiration, mediastinoscopy and video-assisted thoracoscopic surgery. Some of these procedures can also show if cancer has spread beyond the lungs to other parts of the body. Chest x-ray
An x-ray of the chest can identify tumours as small as one centimetre in diameter. Occasionally, a lung cancer is found on a chest x-ray that has been taken for other reasons. Sputum cytology
The sputum cytology test is an examination of sputum under a microscope to check for abnormal cells. Sputum is the liquid that you cough up from your lungs. Early-morning samples are collected for several days – you will be asked to cough deeply to bring up liquid from your lungs. You can do this at home, storing the sample in the fridge before taking it to the doctor or pathology collection centre. Bronchoscopy
An instrument called a bronchoscope is sometimes used to help diagnose lung cancer. This is a flexible tube that can be inserted into the nose or mouth and down the trachea. It allows the doctor to look at the lungs and take a sample of tissue, if necessary. This procedure is done after you have had a light sedative and been given a local anaesthetic spray to the back of the throat. It can be uncomfortable but is not painful. Fine-needle aspiration
This procedure is done if you have a suspicious-looking lump (tumour) that cannot be sampled using bronchoscopy but can be reached by putting a needle into the tumour. It is usually done in hospital. You will have a local anaesthetic before the doctor inserts the needle through the chest wall and into the tumour, guided by x-ray pictures, and removes some tissue. A procedure called thoracentesis also uses a fine needle. Instead of going into the tumour, fluid from around the pleural space is sampled to check for cancer cells. Mediastinoscopy
In this procedure, the doctor is able to look at lymph nodes in the centre of the chest, to see if they are affected by cancer. The procedure is similar to bronchoscopy, but the tube is inserted through an incision in the neck and fed down to the lymph nodes. The doctor can remove a sample of tissue if necessary. This procedure is done using a general anaesthetic. It is usually a day procedure, but sometimes includes an overnight stay in hospital. Video-assisted thoracoscopic surgery
Thoracoscopes are instruments like bronchoscopes and mediastinoscopes. They are inserted into the chest cavity through small incisions in the skin. The doctors can see inside your chest using these instruments, and take tissue samples if necessary. Often the doctor uses a very small video camera and is able to guide the instruments by watching the video screen. You may have up to three small cuts made in your chest, one for the camera and two for the surgical instruments. You will have a general anaesthetic and be in hospital for two or three days. CT scan
A computerised tomography (CT) scan can be used to identify smaller tumours than those found by x-rays. It can also assess whether lymph nodes are enlarged. A CT scan is a special type of x-ray that gives a three-dimensional picture of the organs and other structures (including any tumours) in your body. CT scans are usually done at a hospital or a radiology service. It usually takes about 30-40 minutes to complete this painless test. You will be asked to lie flat on a table while the CT scanner, which is large and round like a doughnut, rotates around you. A dye may be injected into a vein, probably in your arm, before the scan. This will make the pictures that the scanner takes clearer. You will be asked not to eat or drink for a while before you have you scan. Most people are able to go home as soon as their scan is over. Other scans
Other types of scan may be used. A bone scan can show whether cancer has spread to the bones. A small amount of radioactive substance is injected into a vein. It travels through the bloodstream and collects in areas of abnormal bone growth. An instrument called a scanner measures the radioactivity levels in these areas and records them on x-ray film. Ventilation/perfusion lung scans can calculate how much lung function will be lost if lung tissue is removed. Positron emission tomography, also known as a PET scan, involved the injection of radioactive glucose solution into the body. Because cancer cells use more glucose than most normal cells, the PET scanner will detect increased quantities of the radioactive glucose in those areas of the body to which the cancer has spread (if it has spread), for example to the other organs or lymph nodes. Other tests
You may also have blood tests and breathing tests. If surgery is contemplated, it is very important to measure your breathing. People who smoke develop emphysema and may have a reduced breathing capacity. ‘Staging’ the disease
The tests described above show whether you have cancer, and if you do, where the primary cancer is and whether the cancer cells have spread to other parts of your body (this is known as ‘metastasis’). This helps your doctors ‘stage’ the disease so they can work out the best treatment for you. Non-small cell lung carcinoma is staged in the following way: Stage 0: Also called carcinoma in situ. The cancer cells are confined to the surface lining of the airway and have not spread into the underlying tissues. Stage I (1): This may be a relatively small, self contained tumour or a larger tumour that has spread within one lung. Stage II (2): Includes tumours that have spread to the chest wall. Stage IIIa (3a): The tumour has spread to the chest wall or diaphragm near the lung. Cancer cells have spread to lymph nodes on the same side of the mediastinum. Stage IIIb (3b): The cancer is close to or involving the trachea or major blood vessels, or has spread to lymph nodes in the neck or to the other side of the mediastinum. Stage IV (4): The defining feature of Stage IV lung cancer is that cancer cells have spread to distant parts of the body and metastasised (formed secondary tumours). Small cell carcinoma is staged in the following way: Limited stage: Cancer is found in one lung and nearby lymph nodes. Extensive stage: The cancer has spread beyond the lung of origin to the opposite lung or to distant organs. Recurrent: Cancer returns after it has been treated. Treatment
The main treatments for lung cancer are surgery, radiotherapy (x-ray treatment) and chemotherapy (drug treatment). The choice of treatment will depend on whether the cancer has spread beyond the lung, whether your lungs are functioning properly and your general health. The aim of treatment is to keep you as well and symptom free as possible, even if your cancer cannot be cured. Surgery
If your cancer has not spread beyond the lungs, your health (apart from the cancer) is reasonably good and your breathing capacity is sufficient, the treatment that gives the best chance of cure is surgical resection.
The most common operation, called a lobectomy, removes the affected part of the lung. Occasionally, the whole lung needs to be removed and this is called a pneumonectomy.
In patients with reduced breathing, smaller parts of the lung are removed to try to preserve breathing capacity. While these operations preserve breathing capacity, there is more likely to be a recurrence. You doctor will advise you which procedure is best for you. After the operation
You will have an intravenous drip for a couple of days until you can eat and drink again. There will be one of two tubes in your chest to drain fluid or air away: this is temporary. Regular x-rays will be done to make sure your lung or lungs are working properly.
You will have some pain after the operation. This may last for weeks or longer. Let your doctor or nurses know when you need relief from pain and they will provide painkilling drugs. There is no need to ‘suffer in silence’.
You will probably go home five to 10 days after the operation. You will receive advice about managing at home from your doctor, nurses and physiotherapist.
Recovery can take many weeks for some people; however you may recover more quickly than this.
Exercise will help you to recover. To begin with, you will do breathing exercises and leg exercises; later, walking or swimming will improve your strength and fitness. Your doctor or physiotherapist will recommend the best exercises for you, and tell you when it is safe for you to begin more vigorous exercise.
If your breathing was not affected before the operation, you will probably find that you can breathe normally, even though you have had a lung or part of a lung removed. People who had breathing difficulties before the operation may find that they are more breathless afterwards. Chemotherapy
Chemotherapy is the treatment of cancer using anti-cancer (cytotoxic) drugs. The aim is to kill cancer cells while doing the least possible damage to normal cells. The drugs work by stopping cancer cells from dividing and multiplying.
Chemotherapy is the treatment of choice for patients with small cell lung cancer. As this type of cancer spreads quickly, it is very sensitive to chemotherapy. Unfortunately, although the initial response is usually good, the tumour may recur in a resistant form and only a small number can be considered to be cured. Side effects of chemotherapy
Some drugs used in chemotherapy can cause side effects. They may include feeling sick, vomiting, depression, feeling off-colour and tired, and some thinning or loss of hair from your body and head. These side effects are temporary, and steps can be taken to prevent or reduce them.
Radiotherapy
Radiotherapy treats cancer by using x-rays to kill cancer cells. These x-rays can be precisely targeted onto cancer sites in your body. Treatment is carefully planned to do as little harm as possible to your normal body tissues. Lung function will be damaged if the radiotherapy has to be directed at the lung, and lung function tests will be needed to assess this.
In order to make certain that exactly the same area is treated each time, the radiation therapist will make a number of marks on your skin. These marks will consist of lines, crosses and dots applied with special inks. Sometimes these non-permanent marks will need to be redone during the course of the treatment. Radiotherapy may be used to cure some early lung cancers. It may be used to contain cancer that has spread to the lymph nodes.
When lung cancer cannot be cured, radiotherapy can be used to relieve pain and other symptoms, for example pain caused by metastases in the bones or brain. Treatment that is used to relieve symptoms of disease without attempting to cure disease is called palliative treatment. Side effects of radiotherapy
Radiotherapy can cause temporary side effects including nausea, which can be helped by medication, loss of appetite and tiredness. Skin in the treatment area may become red and sore after two or three weeks of treatment. From the start of your treatment, you will need to take care washing and avoid shaving the area or wearing clothing that rubs. Check with your doctor or nurse before using any talcs and lotions. Ask a member of your radiotherapy treatment team for a cream to ease the burning sensation. Prognosis
As in most type of cancer, the results of treatment are best when the cancer is detected and treated early. People operated on in the early stages of lung cancer have a very good chance of cure. In many people, lung cancer is not discovered while it can still be operated upon. In people with advanced cancer, palliative treatment with radiotherapy can effectively treat many symptoms. People who continue to smoke after lung cancer treatment are at risk of further disease. If you need help quitting smoking, speak to your doctor. You will need to discuss your prognosis with your doctor. Your medical history is unique, so you will need to discuss with someone who knows your medical history what you can expect and the treatment options best for you. Palliative treatment
Palliative treatment is treatment that relieves or soothes pain and other distressing symptoms of illness. Palliative care is available for people who experience pain and distress associated with cancer, whatever their stage of cancer treatment. It is a particularly important type of treatment for people with advanced cancer, who cannot be cured but can expect to live without undue pain and distress. Palliative care includes pain relief using painkilling drugs and other measures including radiotherapy and chemotherapy. Pain is usually well controlled with oral medication and there is no need to fear developing drug dependency. Sometimes fluids build up in the chest because of the spread of the cancer. This can be removed and the space between the lung and the chest wall closed, with an injection of a chemical.
If an airway becomes blocked by a tumour growing in it or by pressure from outside the airway, this can be relieved. A tumour in an airway can be removed using a laser and bronchoscopy; a stent can relieve external pressure on an airway. Sometimes, people develop blood in the sputum (haemoptysis). This may be controlled by laser bronchoscopy or radiotherapy, or by blocking the artery to the affected area.
General practitioners, specialists and specialist palliative care teams in hospital play important roles in palliative treatment for people with early and advanced cancer. Making decisions about treatment
Sometimes it is difficult to make decisions about what is the right treatment for you. You may feel that everything is happening so fast that you do not have time to think things through. Some people find that waiting for test results and for treatment to begin is very difficult. While some people feel that are overwhelmed with information, others may feel that they do not have enough. You need to make sure that you understand enough about your illness, the possible treatment and side effects to make you own decisions.
If you are offered a choice of treatments, you will need to weigh up the advantages and disadvantage of each treatment. If only one type of treatment is recommended, ask your doctor to explain why other treatment choices have not been advised.
Some people with more advanced cancer will always choose treatment; even it only offers a small chance of cure. Others want to make sure that the benefits of treatment outweigh any side effects. Still others will choose the treatment they consider offers them the best quality of life. Some may choose not to have treatment by to have any symptoms managed as they arise in order to maintain the best possible quality of life. Source: http://www.cancer.org.my/types_lung.php
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