Mesothelioma - Signs, symptoms, Diagnosis, Treatment & Prevention

Signs and symptoms :

Symptoms of mesothelioma may not appear until 20 to 50 years after exposure to asbestos. Shortness of breath, cough, and pain in the chest due to an accumulation of fluid in the pleural space are often symptoms of pleural mesothelioma.

Symptoms of peritoneal mesothelioma include weight loss and cachexia, abdominal swelling and pain due to ascites (a buildup of fluid in the abdominal cavity). Other symptoms of peritoneal mesothelioma may include bowel obstruction, blood clotting abnormalities, anemia, and fever. If the cancer has spread beyond the mesothelium to other parts of the body, symptoms may include pain, trouble swallowing, or swelling of the neck or face.

These symptoms may be caused by mesothelioma or by other, less serious conditions.

Mesothelioma that affects the pleura can cause these signs and symptoms:

chest wall pain
pleural effusion, or fluid surrounding the lung
shortness of breath
fatigue or anemia
wheezing, hoarseness, or cough
blood in the sputum (fluid) coughed up
In severe cases, the person may have many tumor masses. The individual may develop a pneumothorax, or collapse of the lung. The disease may metastasize, or spread, to other parts of the body.

Tumors that affect the abdominal cavity often do not cause symptoms until they are at a late stage. Symptoms include:

abdominal pain
ascites, or an abnormal buildup of fluid in the abdomen
a mass in the abdomen
problems with bowel function
weight loss
In severe cases of the disease, the following signs and symptoms may be present:

blood clots in the veins, which may cause thrombophlebitis
disseminated intravascular coagulation, a disorder causing severe bleeding in many body organs
jaundice, or yellowing of the eyes and skin
low blood sugar level
pleural effusion
pulmonary emboli, or blood clots in the arteries of the lungs
severe ascites
A mesothelioma does not usually spread to the bone, brain, or adrenal glands. Pleural tumors are usually found only on one side of the lungs.


Diagnosis :

Diagnosing mesothelioma is often difficult, because the symptoms are similar to those of a number of other conditions. Diagnosis begins with a review of the patient's medical history. A history of exposure to asbestos may increase clinical suspicion for mesothelioma. A physical examination is performed, followed by chest X-ray and often lung function tests. The X-ray may reveal pleural thickening commonly seen after asbestos exposure and increases suspicion of mesothelioma. A CT (or CAT) scan or an MRI is usually performed. If a large amount of fluid is present, abnormal cells may be detected by cytology if this fluid is aspirated with a syringe. For pleural fluid this is done by a pleural tap or chest drain, in ascites with an paracentesis or ascitic drain and in a pericardial effusion with pericardiocentesis. While absence of malignant cells on cytology does not completely exclude mesothelioma, it makes it much more unlikely, especially if an alternative diagnosis can be made (e.g. tuberculosis, heart failure).


If cytology is positive or a plaque is regarded as suspicious, a biopsy is needed to confirm a diagnosis of mesothelioma. A doctor removes a sample of tissue for examination under a microscope by a pathologist. A biopsy may be done in different ways, depending on where the abnormal area is located. If the cancer is in the chest, the doctor may perform a thoracoscopy. In this procedure, the doctor makes a small cut through the chest wall and puts a thin, lighted tube called a thoracoscope into the chest between two ribs. Thoracoscopy allows the doctor to look inside the chest and obtain tissue samples.

If the cancer is in the abdomen, the doctor may perform a laparoscopy. To obtain tissue for examination, the doctor makes a small opening in the abdomen and inserts a special instrument into the abdominal cavity. If these procedures do not yield enough tissue, more extensive diagnostic surgery may be necessary.

Treatment :

Treatment of MM using conventional therapies has not proved successful and patients have a median survival time of 6 - 12 months after presentation. The clinical behaviour of the malignancy is affected by several factors including the continuous mesothelial surface of the pleural cavity which favours local metastasis via exfoliated cells, invasion to underlying tissue and other organs within the pleural cavity, and the extremely long latency period between asbestos exposure and development of the disease.

Surgery :

Surgery, either by itself or used in combination with pre- and post-operative adjuvant therapies has proved disappointing. A pleurectomy/decortication is the most common surgery, in which the lining of the chest is removed. Less common is an extrapleural pneumonectomy (EPP), in which the lung, lining of the inside of the chest, the hemi-diaphragm and the pericardium are removed. It is not possible to remove the entire mesothelium without killing the patient.

Radiation :

For patients with localized disease, and who can tolerate a radical surgery, radiation is often given post-operatively as a consolidative treatment. The entire hemi-thorax is treated with radiation therapy, often given simultaneously with chemotherapy. This approach of using surgery followed by radiation with chemotherapy has been pioneered by the thoracic oncology team at Brigham & Women's Hospital in Boston. [7] Delivering radiation and chemotherapy after a radical surgery has led to extended life expectancy in selected patient populations with some patients surviving more than 5 years. As part of a curative approach to mesothelioma, radiotherapy is also commonly applied to the sites of chest drain insertion, in order to prevent growth of the tumor along the track in the chest wall.

Although mesothelioma is generally resistant to curative treatment with radiotherapy alone, palliative treatment regimens are sometimes used to relieve symptoms arising from tumor growth, such as obstruction of a major blood vessel. Radiation therapy when given alone with curative intent has never been shown to improve survival from mesothelioma. The necessary radiation dose to treat mesothelioma that has not been surgically removed would be very toxic.

Chemotherapy :

In February 2004, the United States Food and Drug Administration approved pemetrexed (brand name Alimta) for treatment of malignant pleural mesothelioma. Pemetrexed is given in combination with cisplatin. Folic acid is also used to reduce the side-effects of pemetrexed.


Immunotherapy :

Treatment regimens involving immunotherapy have yielded variable results. For example, intrapleural inoculation of Bacillus Calmette-Guérin (BCG) in an attempt to boost the immune response, was found to be of no benefit to the patient (while it may benefit patients with bladder cancer). Mesothelioma cells proved susceptible to in vitro lysis by LAK cells following activation by interleukin-2 (IL-2), but patients undergoing this particular therapy experienced major side effects. Indeed, this trial was suspended in view of the unacceptably high levels of IL-2 toxicity and the severity of side effects such as fever and cachexia. Nonetheless, other trials involving interferon alpha have proved more encouraging with 20% of patients experiencing a greater than 50% reduction in tumor mass combined with minimal side effects.

Heated Intraoperative Intraperitoneal Chemotherapy :

A procedure known as heated intraoperative intraperitoneal chemotherapy was developed by Paul Sugarbaker at the Washington Cancer Institute.[7] The surgeon removes as much of the tumor as possible followed by the direct administration of a chemotherapy agent, heated to between 40 and 48°C, in the abdomen. The fluid is perfused for 60 to 120 minutes and then drained.

This technique permits the administration of high concentrations of selected drugs into the abdominal and pelvic surfaces. Heating the chemotherapy treatment increases the penetration of the drugs into tissues. Also, heating itself damages the malignant cells more than the normal cells.


Prevention :

What can be done to prevent the disease? Since the 1970s, the Environmental Protection Agency and the Occupational Safety and Health Administration have regulated the asbestos industry in the U.S. In the past, asbestos was used as a fire retardant and an insulator. Other products are now used in its place. The controversy involving exposure to different forms of asbestos continues.

There are two major types of asbestos: chrysotile and amphibole. It is thought that exposure to the amphibole form is more likely to cause mesothelioma. However, chrysotile has been used more frequently, hence many mesotheliomas are caused by chrysotile.

Removal is taking place in schools and other public buildings throughout the U.S. The hope is that these measures will greatly reduce the occurrence of this cancer.

What are the long-term effects of the disease? A mesothelioma is a highly aggressive tumor that is generally deadly. Current treatment of malignant mesothelioma is designed to make the person with cancer comfortable. Although long-term survival cannot usually be expected, the case of famed paleontologist Stephen Jay Gould is a noted exception.

What are the risks to others? Mesothelioma is not contagious and cannot be passed from one person to another. The exposure to the asbestos that caused the cancer occurred many years to several decades before the disease appeared. People who live with asbestos workers have a higher risk of getting this cancer.

What happens once treatment is over? Although mesothelioma is very unpleasant it's still important for person after treatment is over to keep up all follow-up appointments and that's vital because further testing is always needed to check whether cancer is coming back or to examine possible side effects that could be rather unpleasant and what's even worse permanent.

Mesothelioma - An Introduction...

Mesothelioma is a form of cancer that is almost always caused by previous exposure to asbestos. In this disease, malignant cells develop in the mesothelium, a protective lining that covers most of the body's internal organs. Its most common site is the pleura (outer lining of the lungs and chest cavity), but it may also occur in the peritoneum (the lining of the abdominal cavity) or the pericardium (a sac that surrounds the heart).

Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles, or have been exposed to asbestos dust and fibre in other ways, such as by washing the clothes of a family member who worked with asbestos, or by home renovation using asbestos cement products. Unlike lung cancer, there is no association between mesothelioma and smoking.

Cancer !!! An Introduction...

What is cancer?


All living things - ourselves included - are made up of cells. Cells are microscopic packages of living material and we have billions of them. They come in many different types: liver cells, brain cells, blood cells and so on. In the normal adult, cells only grow and divide slowly and under very tight control to make sure that the number of cells in each tissue stays the same. Cancer begins when one cells changes and starts growing and dividing rapidly and out of control. This one cells divides to give two cells, then four, eight and so on until they form growing mass of cancer cells - called a tumour.


What do malignant and benign mean?


In some tumours, the cells stay in the same place and as the tumour stops growing before it gets very large - often because it simply runs out space to grow. These are called benign tumours and they are not normally dangerous. We all have benign tumours, such as moles and warts. However, in other tumours the cells are able to invade the surrounding tissue and spread into nearby organs where they can cause serious and, eventually, fatal damage. These are called malignant tumours.


What is metastasis?


In many malignant tumours, as the cells spread, they come across blood vessels. If they actually spread into the blood vessel, they get carried around the body and eventually get stuck in a smaller blood vessel in another part of the body. Here they begin to divide and grow again eventually forming a new tumour. These are called secondary tumours or metastases. This process of cancers spreading around the body is called metastasis.


Do genes cause cancer?


Every cell carries a set of coded instructions for every activity or function that it can perform. Different genes are active in different cells, which is why a brain cell carries out many different activities from muscle cell. Genes also carry the coded instructions for basic functions of the cell such as the way cells grow and divide. The growth and division of normal cells is tightly controlled by the activity of certain genes. However, when these genes are faulty or when they mechanisms controlling the activity of these genes is damaged, it can cause the growth and division of the cells to go out of control - in other words, the become cancerous. Genes themselves do not cause cancer. When they function normally, genes prevent cancer. However, it is when some genes become damaged that they can malfunction and cause cancer.


Can you inherit cancer?


Cancer itself cannot be inherited, but some people do inherit a higher risk of getting cancer. This is because they inherit, from their parents, a slightly damaged version of one of the genes involved in controlling cell division. On its own, this damaged gene is not enough to make cells cancerous. Normally, two or three different genes have to be damaged before a cell will become cancerous. That is why so very few of the billions of cells in our body ever become cancerous. However, if someone starts out with every cell in their body carrying damage in one of these genes, the chance of a cell getting the other types of gene damage and becoming cancerous is much higher. Some of these inherited damaged genes have been identified, such as BRCA1 and BRCA2 which increase the risk of getting breast cancer by five to seven times.


Do tumours need a blood supply?


A tumour usually starts with a single cancerous cell that begins growing and dividing. The resulting mass of cancer cells soon gets large enough to need a new blood supply to provide oxygen and nutrients and to remove waste products. Without a blood supply, the cells in the middle of the tumour will die off. In fact, tumours without a blood supply are unable to grow more that about one millimetre across. As soon as they start growing, tumours release small, hormone-like molecules that cause nearby blood vessels to start growing towards the tumour until they actually form a new branch supplying the tumour with blood.