What is Mesothelioma?

Mesothelioma is a cancer of the mesothelium. The mesothelium is a thin membrane that lines the chest and abdomen and surrounds the organs in these areas. The lining around the lungs is called the pleura and in the abdomen it is known as the peritoneum.

About 2000 people in the UK are diagnosed with mesothelioma each year.

Mesothelioma of the lining of the lungs, known as pleural mesothelioma, is much more common than mesothelioma in the peritoneum. For every one person with peritoneal mesothelioma, there will be about 12 people who have pleural mesothelioma.

Pleural mesothelioma

The pleura has two layers: the inner (visceral) layer, which is next to the lung; and the outer (parietal) layer, which lines the chest wall. The two layers of the pleura are usually in contact and slide over each other as we breathe. The membranes produce fluid, which allows them to slide over each other easily.

When mesothelioma develops in the pleura (pleural mesothelioma), the delicate membranes thicken and may press inwards on the lung. Fluid may also collect between the two layers of the pleura: this is known as a pleural effusion.

Structure of the lungs and pleura

Peritoneal mesothelioma

The lining of the abdomen is known as the peritoneum. It also has two layers: the inner (visceral) layer, which is next to the abdominal organs, and the outer (parietal) layer, which lines the abdominal wall.

If the mesothelioma is in the peritoneum it is called peritoneal mesothelioma and causes thickening of the membranes surrounding the abdominal organs and a collection of fluid in the abdomen. The collection of fluid is called ascites and causes swelling of the abdomen.

Side view of the abdomen. The peritoneum is shown as the thick line surrounding the abdominal organs.

Surgery for mesothelioma

In the uncommon situation where the cancer is only in one area of the pleura (localised), surgery can be used to treat mesothelioma. It may involve removing part, or all, of the pleura and the lung tissue close to it. This is known as pleurectomy. Sometimes the pleura, diaphragm, and the whole lung on the affected side are removed as well as the tumour. This operation is known as extra-pleural pneumonectomy.

At present it is not clear whether surgery can give better control of symptoms or can help people to live for longer than just using active symptom control. A research trial is currently looking at whether extra-pleural pneumonectomy can give a better quality and length of life for people with localised pleural mesothelioma. This trial is called the MARS trial. You may be invited to take part if your doctor thinks that surgery could possibly be helpful for you.

It is not usually possible to surgically remove abdominal (peritoneal) mesothelioma. If surgery is possible, it is carried out by surgeons with specialist expertise in treating mesothelioma. However, the operation is not likely to cure the mesothelioma.

It is important that you discuss any operation fully with your doctor beforehand so that you understand what it involves. Remember, no operation or procedure will be done without your consent.

Surgery may sometimes be combined with radiotherapy or chemotherapy.

After your operation

It can take many weeks to recover fully from a lung operation, although some people recover more quickly than others. There are things you can do to help speed up your recovery. After your operation, you will be encouraged to start moving about as soon as possible. Even if you have to stay in bed, the nurses will encourage you to do regular leg movements to help to prevent blood clots developing in your legs. A physiotherapist will visit you on the ward to help you with breathing exercises.

Drips and drains

A drip (intravenous infusion) will be used to give you fluids for a couple of days, until you are able to eat and drink normally again. You will also have drainage tubes in your wound. These are usually removed about 2–7 days after your operation depending on your recovery. X-rays will be taken regularly to make sure your lung is working properly.

Pain

It is normal to have some pain or discomfort after your operation. This can usually be controlled using painkilling drugs. Let your doctor or one of the nurses know if you have any pain so they can treat it as soon as possible. Mild discomfort or pain in your chest can last for several weeks and you will be given some painkilling tablets to take home with you.

Going home

You can usually go home after about seven days after a pleurectomy. If you have an extra-pleural pneumonectomy it will probably be about 14 days before you are ready to go home. If you think you might have problems when you go home – for example, if you live alone or have several flights of stairs to climb – let one of the nurses or the hospital social worker know when you are admitted to the ward, so that help can be arranged.

When you go home, it is important to exercise gently, to build up your strength and fitness. Walking and swimming are suitable for most people after surgery to the lung area. But it is a good idea to check with your doctor or physiotherapist which kind of exercise would be suitable for you.

Active symptom control as a treatment for mesothelioma

This means that if you have any symptoms, these are treated with appropriate medicines such as painkillers, or drugs to reduce breathlessness or improve appetite. Radiotherapy may be used to reduce symptoms if needed. Chemotherapy may also sometimes be used to shrink the mesothelioma and control symptoms.There are a number of ways to help symptoms caused by the mesothelioma. Pleural mesothelioma commonly causes breathlessness or difficulty with breathing. Breathlessness can sometimes be caused by a build-up of fluid around the lungs (pleural effusion). Your doctor may be able to drain this fluid under a local anaesthetic so that your breathing becomes easier. It may be necessary to have the fluid removed on a regular basis.Talcum powder (talc), or a particular chemical powder, may be put into the pleural space through a tube. This procedure is called pleurodesis and causes inflammation of the pleural membranes, which then stick together to prevent the fluid from building up again. This can be done using keyhole surgery and is then called video assisted thorascopic surgery (VATS).Fluid in the abdomen (ascites) can also be removed using a needle inserted under local anaesthetic.You may be given medicines to help your breathing and also to control pain. If at any time you feel that your medicines are not working, let your doctor know as soon as possible so that the dose can be altered or the medicines changed.If you have any symptoms that are not easily controlled, you can be quickly referred to a relevant specialist such as a pain relief service, physiotherapist or symptom control team. The aim of this type of treatment is to keep you as free as possible of symptoms and to give you the best possible quality of life.Other helpful remedies include relaxation techniques and physiotherapy, and your GP or a local cancer self-help group can give you more details about these. You may also find it helpful to look at our sections on controlling cancer pain, controlling the symptoms of cancer and complementary therapies.Your doctor will discuss the different approaches to treatment, and you may need time to consider the options. You can then talk it over with family or friends before you make any firm decisions. If you would rather talk to someone outside your situation, you may find it helpful to speak to one of the nurses in our cancer support service.

Treatment of mesothelioma

Once the doctors know the stage of the mesothelioma they will be able to plan the most appropriate treatment.

The treatment for mesothelioma depends on whether it is only in one place or has spread. Currently, there is no cure for mesothelioma, unless it can be removed by an operation. Unfortunately, when mesothelioma is diagnosed, it has usually already spread beyond the point where it could be removed surgically.

The usual treatment for mesothelioma in this situation is active symptom control.

Radiotherapy may be used as part of treatment to try to cure mesothelioma. Most often it is used to control symptoms. Chemotherapy can also be used to control symptoms and to slow the growth of mesothelioma.

Multidisciplinary team

If your tests show that you have mesothelioma, you will be looked after by a multidisciplinary team. This is a team of staff who specialise in treating mesothelioma and in giving information and support. It will normally include:

• surgeons who are experienced in chest surgery
• specialist nurses who give information and support
• oncologists – doctors who have experience in mesothelioma treatment using chemotherapy and radiotherapy
• symptom-control specialists
• radiologists who help to analyse x-rays
• pathologists who advise on the type and extent of the cancer.

Other staff will also be available to help you if necessary, such as:

• physiotherapists
• counsellors and psychologists
• social workers
• dietitians.

Together they will be able to advise you on the best course of action taking into account a number of factors. These include your age, general health, and how the mesothelioma is affecting you.

Occasionally your doctors may offer you a choice of treatments. Sometimes people find it very hard to make a decision. If you are asked to make a choice, make sure that you have enough information about the different treatment options, what is involved and the side effects you might experience, so that you can decide what is the right treatment for you.

Remember to ask questions about any aspects that you do not understand or feel worried about. You may find it helpful to discuss the benefits and disadvantages of each option with your cancer specialist, nurse specialist or with the nurses in our cancer support service.

If you have any questions about your own treatment, don't be afraid to ask your doctor or nurse. It often helps to make a list of questions and to take a close friend or relative with you.

Second opinion

Even though a number of cancer specialists work as a team to decide on the most suitable treatment, you may want to have another medical opinion. Most doctors will be willing to refer you to another specialist for a second opinion if you feel that it will be helpful. The second opinion may take some time to organise and may cause a delay in the start of your treatment, so you and your doctor need to be confident that it will be helpful.

If you do go for a second opinion, it may be a good idea to take a friend or relative with you, and to have a list of questions so you can make sure your concerns are covered during the discussion.

Giving your consent

Before you have any treatment your doctor will explain its aims to you. You will usually be asked to sign a form saying that you give your permission (consent) for the hospital staff to give you the treatment. No medical treatment can be given without your consent, and before you are asked to sign the form, you should have been given full information about:

• the type and extent of the treatment you are advised to have
• the advantages and disadvantages of the treatment
• any other treatments that may be available
• any significant risks or side effects of the treatment.

If you do not understand what you have been told, let the staff know straight away so that they can explain again. Some treatments are complex, so it is not unusual for people to need their treatment to be explained more than once.

Patients often feel that hospital staff are too busy to answer their questions, but it is important for you to be aware of how the treatment is likely to affect you and the staff should be willing to make time for you to ask questions.

You can always ask for more time to decide about the treatment, if you feel that you can't make a decision when it is first explained to you. You are also free to choose not to have the treatment, and the staff can explain what may happen if you do not have it.

Benefits and disadvantages of treatment

Many people are frightened at the idea of having cancer treatments, particularly because of the side effects that can occur. Some people ask what would happen if they did not have any treatment.

Although cancer treatments can cause side effects, these can usually be controlled with medicines.

Treatment can be given for different reasons and the potential benefits will vary depending upon the individual situation. For the few people with early-stage mesothelioma, surgery and radiotherapy may be given with the aim of curing the cancer.

However, in most people with mesothelioma, the cancer is at a more advanced stage and any treatment given is with the aim of controlling it, which for some people may lead to an improvement in symptoms and a better quality of life. But, for some people in this situation the treatment will have no effect upon the cancer and they will get the side effects of the treatment without any of the benefit.

When a cure is not possible and the aim of treatment is to control the cancer for a period of time, it may be difficult to decide whether to go ahead with treatment. Making decisions in these circumstances is always hard, and you may need to discuss your treatment and symptom control in detail with your doctor.

Staging of mesothelioma

The stage of a cancer is a term used to describe its size and whether it has spread beyond its original site. Knowing the extent of the cancer helps the doctors to decide on the best treatment. There are several staging systems for pleural mesothelioma.

A commonly-used system is described below:

Localised malignant mesothelioma

Stage 1 The cancer cells are found in the pleura near the lung and heart or in the diaphragm or the lung.

Advanced malignant mesothelioma

Stage 2 The cancer has spread beyond the pleura to lymph nodes in the chest.

Stage 3 The cancer has spread into one or more of the chest wall, the centre of the chest, the heart, the diaphragm, the abdominal lining, and the nearby lymph nodes.

Stage 4 The cancer has spread to distant organs or tissues.

A staging system has not yet been established for peritoneal mesothelioma. But sometimes doctors may use the TNM staging system for this cancer. The initials T, N and M stand for 'tumour', 'nodes' and 'metastases'.

• T describes the size of the tumour
• N describes whether the cancer has spread to the lymph nodes
• M describes whether the cancer has spread to another part of the body.

How mesothelioma is diagnosed

Most people begin by seeing their GP when they have symptoms. Your GP will examine you and may arrange for you to have some tests or x-rays. You may be referred to hospital for these tests and for specialist advice and treatment. At the hospital, the doctor will take your medical history and occupational history before doing a physical examination.

Chest x-ray

A chest x-ray will be taken to check for any abnormalities in your lungs, such as thickening of the pleura or fluid around the lungs. However, there can be other causes of thickening of the pleura and peritoneum (and fluid around the lungs or in the abdomen) apart from mesothelioma.

The following tests may also be needed to diagnose mesothelioma, and your doctor may arrange for you to have one or more of them at the hospital.

CT scan

A CT scan (computerised tomography scan) takes a series of x-rays, which build up a three-dimensional picture of the inside of the body. The scan is painless but takes from 10 to 30 minutes. CT scans use a small amount of radiation, which will be very unlikely to harm you and will not harm anyone you come into contact with. You will be asked not to eat or drink for at least four hours before the scan.

CT scans of the chest and of the abdomen will show the size and position of the mesothelioma and whether it has spread to other parts of the body.

You may be given a drink or injection of a dye that allows particular areas of your body to be seen more clearly. For a few minutes, this may make you feel hot all over. If you are allergic to iodine, or have asthma, you could have a more serious reaction to the injection, so it is important to let your doctor know beforehand.

You will probably be able to go home as soon as the scan is over.

Having a CT scan

Pleural or peritoneal aspiration

If there is fluid in your chest or abdomen, the doctor can take a sample by using a local anaesthetic and passing a needle through the skin into the fluid. Some of the fluid is then drawn off into a syringe and can be analysed in the laboratory to look for mesothelioma cells.

Taking fluid from between the pleura is known as a pleural aspiration and taking fluid from the abdomen is known as drainage of ascites (or peritoneal aspiration).

Biopsy

If you need a biopsy, your doctor will take a sample of tissue from the thickened pleura or peritoneum. A local anaesthetic is used to numb the area and a special type of needle is passed through the skin into the tumour. The needle has a tip that can cut out a sample of the tumour. The doctor may use ultrasound or a CT scanner to position the needle accurately. An ultrasound uses sound waves to build up a picture of the organs in a part of the body. A small device is passed over the skin to show the doctor where the tumour is and guide the needle into the right place.

Sometimes the doctor will want to look at the area of the pleura or the peritoneum directly to get a sample of tissue from the right area. This is done by using a thin flexible tube with a light and camera at the end. The tube (endoscope) can be passed through the skin of the chest, where it is called thoracoscopy, or the abdomen, where it is called laparoscopy. The procedure is done under a general anaesthetic by a surgeon. You will usually be able to go home the same day.

Your doctors may want to check for any signs of spread of the cancer to the nearby lymph glands in the centre of the chest. This central area, around the lower part of the windpipe, is called the mediastinum and the lymph glands which are found there are the mediastinal lymph nodes. This test is called a mediastinoscopy. The test is done under a general anaesthetic and will mean a short stay in hospital. A small cut is made through the skin at the base of the neck. A tube, like a small telescope, is passed into the chest through the hole created by the cut. The doctor can use this tube to examine the area. Samples can be taken for examination under a microscope.

Analysing the biopsy in the laboratory is the only way your doctors can make the diagnosis of mesothelioma. Sometimes, even after taking a biopsy, the doctors may not be sure of the diagnosis, because mesothelioma can be very difficult to distinguish from other illnesses. In this situation, the biopsy samples may be sent to other laboratories to confirm the diagnosis, some of your tests may need to be repeated or you may be referred to another hospital for a second opinion.

Waiting for your test results

It will probably take several days for the results of your tests to be ready and a follow-up appointment will be arranged for you before you go home. This waiting period is likely to be an anxious time for you and it may help to talk things over with a close friend or relative. You may want to ring our cancer support service to ask any questions you may have.

Symptoms of mesothelioma

Mesothelioma often starts as a lot of tiny lumps (nodules) in the pleura, which may not show up on scans or x-rays until they are quite large. The main symptoms of pleural mesothelioma are breathlessness and chest pain. Some people find that their voice becomes hoarse and they have a cough that does not go away.

Peritoneal mesothelioma often causes swelling and pain in the abdomen.

General symptoms

Both types of mesothelioma can cause other general symptoms, such as loss of appetite, sweating (especially at night), weight loss and tiredness. As many of these symptoms can also be caused by other illnesses, your doctor will need to do a series of tests before a diagnosis can be made.