A B C D E F G H I J K L M N O P R S T U V W

CANCERS OF THE LUNG

What is Cancer of the Lung ?

Growths, or tumours, are collections of cells, which grow into a lump, which is really of no use to the body. There are two main types of tumours malignant (cancerous) or benign. They can occur in any part of the body, in all shapes and forms. The important feature of malignant tumours is that they spread through tissues locally, and also to other parts of the body. Benign tumours do not do this. In the lungs a wide range of growths occurs. Unfortunately, most are malignant and benign tumours are unusual. The single most important cause of lung cancer is smoking. Other causes of lung cancer include tumours, which have spread from other parts of the body, such as breast, stomach or bowel: these are called secondary tumours, and they usually occur late in the course of the disease. The most important, however, is primary lung cancer. It is a very serious disease, and is the commonest cause of death from cancer in the Western world in women as well as men. The early symptoms are similar to those of other lung conditions: cough, breathlessness or a lung infection which does not clear quickly. Other symptoms are the coughing up of blood and weight loss.

How does Cancer of the Lung occur ?

Primary lung cancer usually starts in the breathing tubes (bronchi). Most tumours probably begin with irritation of the lining of the bronchi. This causes a build-up of cells. This build-up gradually changes into an uncontrolled growth. It will usually contain one of four cell types. The sort of cell in the tumour is important, because treatment is different for each. They are given names, depending on their appearance through a microscope. The four common cell types in lung cancer are: squamous, adeno-, large and small cell carcinoma. In addition, there are other growths, which go by special names. Mesothelioma is a very rare cancer of the lining of the lung. Carcinoid tumours produce a chemical, 5-hydroxytryptamine (5HT), which causes symptoms of flushing, high blood pressure and diarrhoea. Surgery will often cure this type of tumour. A hamartoma is a rare benign tumour, which shows up on a chest x-ray as a large round shadow. It usually causes no problems, but is usually best removed by surgery.

Why does Cancer of the Lung occur ?

Smoking is by far the commonest cause of all sorts of lung cancer. The link with smoking was first discovered in 1953 by two British researchers (Doll and Peto). The risk rises with the number of cigarettes smoked, and falls as the years go by after giving up smoking. In countries where the smoking rate has fallen, the death rate from lung cancer has also fallen. Cigarette smoke contains nicotine, tar, carbon monoxide and thousands of other chemicals. Many of these irritate the lining of the bronchi, causing changes in the cells, which can lead on to cancer. Passive smoking breathing in other people's smoke even if a non-smoker is also associated with an increased risk. There are other less frequent causes. Being exposed to asbestos is one that is well known; and there are other chemicals and gases such as radon.

Treatment Involved for Cancer of the Lung

Treatment of primary lung cancer varies, and depends on three things: firstly the type of cell involved in the tumour; secondly the extent of spread of the disease at the time of diagnosis; and thirdly the state of general health of the patient. For the type of cell, an investigation called bronchoschopy is usually carried out. This involves passing a flexible telescope through the mouth into the bronchi. This allows the doctor to look directly at the growth, and take a biopsy, which can then be examined under the microscope. If this is not possible, there are other ways of finding out the cell type (cytology); one can examine sputum and sometimes take a sample of cells through a fine needle passed into the tumour itself, through the skin of the chest wall. Surgery offers a chance of complete cure, but is suitable for only a minority of patients. In the operation, either a portion of lung is removed (lobectomy) or else an entire lung (pneumonectomy). Radiotherapy (x-ray treatment) may be offered; either after surgery, or on its own as a means of preventing the spread of the growth. Chemotherapy (treatment by drugs) is used in a number of cases and depends on the type of cell in the growth. New treatment and new ways of giving these are constantly being developed by lung cancer specialists.

During Treatment for Cancer of the Lung

All the treatments have some side effects. Surgery for lung cancer is usually a major operation, and has a long recovery phase. Radiotherapy can cause sickness, diarrhoea, indigestion and headaches, and similar symptoms may happen with chemotherapy.

After Treatment for Cancer of the Lung

Lung cancer is one of the most aggressive of all cancers. Untreated it will nearly always prove fatal - and sooner rather than later.

If Cancer of the Lung is Left Untreated

It is important to look out for a recurrence of symptoms that started the illness. These may be a cough, particularly the coughing up of blood and shortness of breath. Sometimes rather unusual effects of the cancer can occur. Hormones can be released which produce nausea and weakness. They may cause muscles to wither and a feeling of vagueness and confusion. If the cancer spreads, secondary growths can occur in the bones, particularly the spine, in the liver, or even in the brain.

Effects on Family of Cancer of the Lung

Your family and friends need to be aware of the symptoms and problems caused by lung cancer, so that they can provide positive support when required. During treatment, particularly, a lot of support is needed to cope with a very demanding time. It is important to give all patients the opportunity of talking freely about their illness. This can be difficult for men, even with family and friends.