Malignant Mesothelioma Cancer

Malignant mesothelioma is a cancer that is unique to those who have been exposed to asbestos. For many years mining companies have known about the connection between mesothelioma and asbestos exposure, but chose not to inform their employees. Moreover, while many employees in asbestos-related industries became sick and suffered lung disease, asbestosis, and mesothelioma, some companies had their doctors falsely diagnose those employees with emphysema and lung cancer caused by smoking. There is no known cure for mesothelioma Common Mesothelioma Cancer Symptoms Persistent coughing Coughing blood Shortness of breath Pain in chest Pain in the abdomen Fatigue Significant weight loss Types of Malignant Mesothelioma Cancer > Pleural Mesothelioma> Peritoneal Mesothelioma There are two common types of malignant mesothelioma: Pleural mesothelioma and Peritoneal mesothelioma. Pleural mesothelioma is cancer of the pleura, a sac that lines the lungs. The pleura is a membrane that lines the pleural cavities surrounding the lungs. When inhaled, asbestos fibers are absorbed into the lungs, eventually making their way to the edges of the lungs and into the pleura, causing lesions and scarring. Eventually, malignant mesothelioma cancer develops as a result of the damage caused by the asbestos fibers. Peritoneal mesothelioma is much more rare than pleural mesothelioma, accounting for roughly 10 percent of all mesothelioma cases. While asbestos is to blame for peritoneal mesothelioma, it is not known exactly how asbestos fibers make their way into the peritoneal mesothelium. Peritoneal mesothelioma cancer affects the lining of the abdomen instead of the lining of the lungs and chest cavity. Most people who suffer from malignant mesothelioma or asbestosis have been exposed to asbestos on a daily basis over a long period of time. Asbestos is used in many tiles, brake pads, and insulation products because of its ability to add strength and heat resistance. However, those who work with products containing asbestos, or factories that produce asbestos products, are most at risk

Five Steps to Selecting the Right Mesothelioma Attorney

1. Ignore the Ads Many asbestos lawyers advertise on television, however, you should not use a TV commercial as the reason to hire an attorney. Actual credentials are what counts. For example, what type of accomplishments has the lawyer achieved? How committed are they to cancer cases? How many other cases have they handled? Many of the best firms do not advertise much because they do not have to. 2. Bigger is Not Better Big law firms with lots of money and lawyers are not always the best choice for a client. At larger firms, a client may be handed-off to paralegals and younger staff attorneys. (The "big guns" are the ones who show up in court if the case ends up going there. But, most asbestos cases are settled out of court.) You don't want a young lawyer to "learn the ropes" at your expense. It's best to find experienced lawyers who will personally handle your case regardless of the size of their offices or staff. In addition, the lawyer or law firm you choose does not have to be in the same state as you. Most lawyers are able to practice in any state for a specific case. 3.Understand Fees Contingency is the term that means that the lawyer gets paid only after they collect money for you. Nearly all asbestos related lawsuits are handled on a contingency basis. The amount of the contingency fee that your lawyer can charge varies by state. It is usually between 33% and 40% of the amount that is awarded to you after expenses are deducted. It is important to discuss fees openly, ask what services they cover, and whether there will be any extra charges. 4. Trusted Partner For something as important as a mesothelioma lawsuit, your attorney should not only be experienced, skilled, and dedicated, but also a trusted partner who keeps you well informed. You have the right to know and understand every step of the legal process and to be included in key decisions about your case. You should ask a potential attorney to explain how they intend to include you in the decision-making. Warning Signs Finally, here are three warning signs that an attorney may not be right for you: The lawyer is hard to reach, does not return calls promptly, or your calls are returned by someone else. The lawyer seems uninterested in your opinions. The lawyer asks you questions that make you doubt their competence or experience.

Mesothelioma without asbestos exposure

For a time, mesothelioma was thought to be exclusively related to asbestos, but more recent reviews indicate that a significant number of cases have occurred in the absence of any known asbestos exposure. Although the association between amphibole asbestos and mesothelioma is indisputable, fewer than 10% of the people exposed to asbestos develop mesothelioma, and fiarly large proportions (up to 50% according to some authors) of the reported cases have no documented exposure to asbestos. A comprehensive survey of adult mesothelioma cases in Canada and the U.S. carefully classified patients based on their likelihood of past exposure to asbestos. The researchers found that asbestos exposure had been unlikely in between 1/4 and 1/3 of cases (McDonald & McDonald, 1980). While it is well documented that asbestos-induced mesothelioma has a latency of 20 years or more, a number of studies have highlighted pleural and pericardial mesotheliomas in children as young as 1-1/2 years old (Lemesch et al., 1976). Surveys of reported mesotheliomas in the U.S., Canada and Israel found a combined total of more than 110 cases in persons under the age of 20. In addition to these unexplained cases of mesothelioma, a number of other fibrous and non-fibrous materials have been associated with mesothelioma induction. It is now generally accepted in the scientific community that durable, long and thin fibres have fibrogenic and carcinogenic potential. A number of natural and man-made fibres with these characteristics have been established as the cause of mesothelioma in laboratory animals. These include glass fibres, aluminum oxide, attapulgite, dawsonite, silicon carbide and potassium titanate (Stanton et al., 1977). The reported outbreak of mesothelioma in rural Turkey has been associated with exposure to fibrous zeolite found in these regions. In his 1980 report, Baris had identified 185 cases of erionite/zeolite-related mesothelioma in two areas of Turkey with no local asbestos deposits or industry. Several non-fibrous agents, both organic and inorganic, have also been shown to induce malignant mesothelioma. For example, a causal link between mesothelioma and radiation has been established based on numerous case reports of mesotheliomas developing at the exact sites of radiation therapy. Other suspected causes include biogenic silica fibres, chronic irritation stemming from tuberculosis and other factors, and heavy metals such as beryllium Polio vaccines and the SV40 virusMore recently, it has been reported that a virus (SV40) contaminating some polio vaccine preparations may well be associated with mesothelioma, as some DNA sequences of the virus are sometimes found in cancerous mesothelial cells. These vaccine preparations had been produced in 1954, some eight years before SV40 was first isolated, and had been prepared by growing polio virus in cell cultures from rhesus monkey kidney cells. As a result, millions of people have been injected with SV40-contaminated polio vaccines. Recent findings by Dr. M. Carbone and colleagues of the Dept. of Pathology at the University of Chicago and by co-workers at the National Cancer Institute first indicated that the SV40 virus, which induces mesothelioma in hamsters, is also oncogenic for humans. Later on, they found SV40-like DNA sequences in human mesothelioma cases (Carbone et al., 1994). Similar evidence is now beginning to appear from France and the U.K. Recent evidence of the significance of the SV40 virus and other potential sources of mesothelioma, suggests that factors other than asbestos exposure may have played a role in recently reported mesothelioma cases in Europe in which the victims are reported to have had only casual, low level contact with asbestos-containing products.

Chrysotile, tremolite and mesothelioma

Although it has been demonstrated that there is a very weak association between chrysotile exposure and mesothelioma, the presence of occasional fibrous tremolite, an amphibole mineral, in some chrysotile ore body has been cited as a potential risk factor amongst chrysotile workers. The available evidence, however, shows that mesotheliomas in chrysotile mining populations are extremely rare relative to rates in amphibole-exposed populations. In fact, less than 40 mesothelioma cases over several decades have been reported amongst chrysotile miners and millers (McDonald et al. 1993). In their analysis of the implications of the 37 mesothelioma cases identified up until 1992 in the 11,000 person cohort, McDonald & McDonald (1995) found that they were concentrated in workers from specific areas of the mines. Further post-mortem lung tissue analysis showed that workers in these areas had tremolite lung content four times higher than those workers in other areas of the mines studied, suggesting that the rare cases of mesothelioma among chrysotile miners are mainly, if not wholly, due to tremolite exposure. The authors note that it should be kept in mind that these mesothelioma cases occurred as a result of long, heavy exposures 20 to 70 years ago. They conclude: "The geological distribution of tremolite within the Québec chrysotile ore body may well vary in time and place and, at present levels of environmental controls, any mesothelioma risk from exposure (...) would be far below the limits of epidemiological detection." The previous review by Dr. Andrew Churg, a pathologist at the University of British Colombia in Canada, supports this conclusion. Churg (1988) writes, "whether tremolite or chrysotile be the critical agent, these observations suggest that chrysotile ore, in both crude and processed forms, does cause mesothelioma in man, but that it is an extremely weak carcinogen and that in today's terms, the doses required are extremely high. As a practical matter, the data indicate that chrysotile will not produce mesotheliomas in those exposed to any current or recently regulated number of fibers..."

Differences in pathogenic potential of fibre types

The results of human epidemiological studies and lung mineral content analyses demonstrate that amphiboles (crocidolite and amosite) are more strongly associated with mesothelioma than is chrysotile. Comparative analysis of fibre durability and chemical composition are helping to explain the greater toxicity of amphiboles. Of the thousands of asbestos-related mesotheliomas reported, virtually all can be directly attributed to exposure to amphiboles. In his widely cited 1988 review of evidence related to mesothelioma causation, Dr. Andrew Churg found that only 53 cases of chrysotile-related mesothelioma had ever been reported from the tens of thousands of workers studied. Of these, ten cases were observed in secondary industry workers for which there was a strong suspicion of amphibole contamination, and 41 cases have occurred in individuals exposed to chrysotile mine dust, which contained traces of the naturally occurring amphibole; tremolite (Churg, 1988). Other evidence of the extremely weak association between chrysotile exposure and mesothelioma has been revealed through the cohort study of some 11,000 Québec chrysotile miners born between 1891 and 1920. The last follow-up of this cohort found that only 37 mesothelioma deaths had been identified among 8,000 deaths from all causes (McDonald et al., 1993). No cases were detected in workers with less than two years of exposure. In addition, unlike crocidolite mining towns, there has been no indication of environmentally-related mesothelioma in chrysotile mining communities. Also in contrast to amphiboles, the risks to household members of chrysotile workers through non-occupational contact appear to be extremely low, as only 2 or 3 isolated cases allegedly related to this "second hand" exposure have been reported. According to Churg, the research data indicates that although chrysotile asbestos can produce mesothelioma in man, the total number of such cases is small and the required doses extremely large. Another important factor is that while in general, amphiboles have been shown to cause lung disease and cancer after short but intense exposures, chrysotile-related illness is associated with very high, long-term exposures only.

Mesothelioma and asbestos exposure

The discovery that exposure to certain types of asbestos is linked to pleural mesothelioma is a result of the pioneering work of Dr. Christopher Wagner, who documented the high incidence of the disease amongst people working at or living near crocidolite (blue) asbestos mines as well as in household members of workers at these mines. Later research by Newhouse and Thompson (1965) also found elevated mesothelioma risks amongst workers (and their household members) at a manufacturing plant using crocidolite. Generally, once diagnosed, cases of mesothelioma are rapidly fatal, but the very long latency of the disease means that symptoms may only begin to appear 20, 30 or even more than 50 years after initial exposures. From the 1940s through to the 1970s, crocidolite and another amphibole, amosite, were used extensively, either alone or in conjunction with chrysotile, in friable insulation applications in the ship-building and construction industries, primarily in North America and Europe. These sprayed-on applications have been discontinued since the 1970s. To a lesser extent, amphiboles were also used in the manufacture of asbestos-cement pipe. In the past, in most of these industries, workers were exposed to extremely high fibre levels. However, what is particularly disturbing is that a number of cases of mesothelioma have been reported in individuals who have had relatively short but intense exposure to amphiboles. The discovery of mesothelioma and its association with certain types of asbestos exposure prompted new research programmes, regulatory attention and increased public awareness of the health risks of asbestos.

Notable people with mesothelioma

Polio vaccines and the SV40 virusMore recently, it has been reported that a virus (SV40) contaminating some polio vaccine preparations may well be associated with mesothelioma, as some DNA sequences of the virus are sometimes found in cancerous mesothelial cells. These vaccine preparations had been produced in 1954, some eight years before SV40 was first isolated, and had been prepared by growing polio virus in cell cultures from rhesus monkey kidney cells. As a result, millions of people have been injected with SV40-contaminated polio vaccines.
Recent findings by Dr. M. Carbone and colleagues of the Dept. of Pathology at the University of Chicago and by co-workers at the National Cancer Institute first indicated that the SV40 virus, which induces mesothelioma in hamsters, is also oncogenic for humans. Later on, they found SV40-like DNA sequences in human mesothelioma cases (Carbone et al., 1994). Similar evidence is now beginning to appear from France and the U.K.
Recent evidence of the significance of the SV40 virus and other potential sources of mesothelioma, suggests that factors other than asbestos exposure may have played a role in recently reported mesothelioma cases in Europe in which the victims are reported to have had only casual, low level contact with asbestos-containing products.

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.

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 a 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.

Paraoccupational Secondary Exposure Family members and others living with asbestos workers have an increased risk of developing mesothelioma, and possibly other asbestos related diseases. This risk may be the result of exposure to asbestos dust brought home on the clothing and hair of asbestos workers. To reduce the chance of exposing family members to asbestos fibres, asbestos workers are usually required to shower and change their clothing before leaving the workplace. Asbestos in buildings Many building materials used in both public and domestic premises prior to the banning of asbestos may contain asbestos. Those performing renovation works or diy activities may expose themselves to asbestos dust. In the UK use of Chrysotile asbestos was banned at the end of 1999. Brown and blue asbestos was banned in the UK around 1985. Buildings built or renovated prior to these dates may contain asbestos materials. Environmental Exposure Incidence of mesothelioma had been found to be higher in populations living near Naturally Occurring Asbestos (NOA).

Occupational

Exposure to asbestos fibres has been recognised as an occupational health hazard since the early 1900s. Several epidemiological studies have associated exposure to asbestos with the development of lesions such as asbestos bodies in the sputum, pleural plaques, diffuse pleural thickening, asbestosis, carcinoma of the lung and larynx, gastrointestinal tumours, and diffuse mesothelioma of the pleura and peritoneum. The documented presence of asbestos fibres in water supplies and food products has fostered concerns about the possible impact of long-term and, as yet, unknown exposure of the general population to these fibres. Although many authorities consider brief or transient exposure to asbestos fibres as inconsequential and an unlikely risk factor, some epidemiologists claim that there is no risk threshold. Cases of mesothelioma have been found in people whose only exposure was breathing the air through ventilation systems. Other cases had very minimal (3 months or less) direct exposure. Commercial asbestos mining at Wittenoom, Western Australia, occurred between 1945 and 1966. A cohort study of miners employed at the mine reported that while no deaths occurred within the first 10 years after crocidolite exposure, 85 deaths attributable to mesothelioma had occurred by 1985. By 1994, 539 reported deaths due to mesothelioma had been reported in Western Australia.

Exposure

Asbestos was known in antiquity, but it wasn't mined and widely used commercially until the late 1800s. Its use greatly increased during World War II. Since the early 1940s, millions of American workers have been exposed to asbestos dust. Initially, the risks associated with asbestos exposure were not publicly known. However, an increased risk of developing mesothelioma was later found among shipyard workers, people who work in asbestos mines and mills, producers of asbestos products, workers in the heating and construction industries, and other tradespeople. Today, the U.S. Occupational Safety and Health Administration (OSHA) sets limits for acceptable levels of asbestos exposure in the workplace, and created guidelines for engineering controls and respirators, protective clothing, exposure monitoring, hygiene facilities and practices, warning signs, labeling, recordkeeping, and medical exams. By contrast, the British Government's Health and Safety Executive (HSE) states formally that any threshold for mesothelioma must be at a very low level and it is widely agreed that if any such threshold does exist at all, then it cannot currently be quantified. For practical purposes, therefore, HSE does not assume that any such threshold exists. People who work with asbestos wear personal protective equipment to lower their risk of exposure

Risk Factor

Working with asbestos is the major risk factor for mesothelioma. A history of asbestos exposure exists in almost all cases. However, mesothelioma has been reported in some individuals without any known exposure to asbestos. In rare cases, mesothelioma has also been associated with irradiation, intrapleural thorium dioxide (Thorotrast), and inhalation of other fibrous silicates, such as erionite. Asbestos is the name of a group of minerals that occur naturally as masses of strong, flexible fibers that can be separated into thin threads and woven. Asbestos has been widely used in many industrial products, including cement, brake linings, roof shingles, flooring products, textiles, and insulation. If tiny asbestos particles float in the air, especially during the manufacturing process, they may be inhaled or swallowed, and can cause serious health problems. In addition to mesothelioma, exposure to asbestos increases the risk of lung cancer, asbestosis (a noncancerous, chronic lung ailment), and other cancers, such as those of the larynx and kidney. The combination of smoking and asbestos exposure significantly increases a person's risk of developing cancer of the airways (lung cancer, bronchial carcinoma). The Kent brand of cigarettes used asbestos in its filters for the first few years of production in the 1950s and some cases of mesothelioma have resulted. Smoking modern cigarettes does not appear to increase the risk of mesothelioma. Some studies suggest that simian virus 40 (SV40) may act as a cofactor in the development of mesothelioma

Pathophysiology

The mesothelium consists of a single layer of flattened to cuboidal cells forming the epithelial lining of the serous cavities of the body including the peritoneal, pericardial and pleural cavities. Deposition of asbestos fibres in the parenchyma of the lung may result in the penetration of the visceral pleura from where the fibre can then be carried to the pleural surface, thus leading to the development of malignant mesothelial plaques. The processes leading to the development of peritoneal mesothelioma remain unresolved, although it has been proposed that asbestos fibres from the lung are transported to the abdomen and associated organs via the lymphatic system. Additionally, asbestos fibres may be deposited in the gut after ingestion of sputum contaminated with asbestos fibres. Pleural contamination with asbestos or other mineral fibres has been shown to cause cancer. Long thin asbestos fibers (blue asbestos, amphibole fibers) are more potent carcinogens than "feathery fibers" (chrysotile or white asbestos fibers). However, there is now evidence that smaller particles may be more dangerous than the larger fibers. They remain suspended in the air where they can be inhaled, and may penetrate more easily and deeper into the lungs. "We probably will find out a lot more about the health aspects of asbestos from [the World Trade Center attack], unfortunately," said Dr. Alan Fein, chief of pulmonary and critical-care medicine at North Shore-Long Island Jewish Health System. Dr. Fein has treated several patients for "World Trade Center syndrome" or respiratory ailments from brief exposures of only a day or two near the collapsed buildings Mesothelioma development in rats has been demonstrated following intra-pleural inoculation of phosphorylated chrysotile fibres. It has been suggested that in humans, transport of fibres to the pleura is critical to the pathogenesis of mesothelioma. This is supported by the observed recruitment of significant numbers of macrophages and other cells of the immune system to localised lesions of accumulated asbestos fibres in the pleural and peritoneal cavities of rats. These lesions continued to attract and accumulate macrophages as the disease progressed, and cellular changes within the lesion culminated in a morphologically malignant tumour. Experimental evidence suggests that asbestos acts as a complete carcinogen with the development of mesothelioma occurring in sequential stages of initiation and promotion. The molecular mechanisms underlying the malignant transformation of normal mesothelial cells by asbestos fibres remain unclear despite the demonstration of its oncogenic capabilities. However, complete in vitro transformation of normal human mesothelial cells to malignant phenotype following exposure to asbestos fibres has not yet been achieved. In general, asbestos fibres are thought to act through direct physical interactions with the cells of the mesothelium in conjunction with indirect effects following interaction with inflammatory cells such as macrophages. Analysis of the interactions between asbestos fibres and DNA has shown that phagocytosed fibres are able to make contact with chromosomes, often adhering to the chromatin fibres or becoming entangled within the chromosome. This contact between the asbestos fibre and the chromosomes or structural proteins of the spindle apparatus can induce complex abnormalities. The most common abnormality is monosomy of chromosome 22. Other frequent abnormalities include structural rearrangement of 1p, 3p, 9p and 6q chromosome arms. Common gene abnormalities in mesothelioma cell lines include deletion of the tumor suppressor genes: Neurofibromatosis type 2 at 22q12 P16INK4A P14ARF Asbestos has also been shown to mediate the entry of foreign DNA into target cells. Incorporation of this foreign DNA may lead to mutations and oncogenesis by several possible mechanisms: Inactivation of tumor suppressor genes Activation of oncogenes Activation of proto-oncogenes due to incorporation of foreign DNA containing a promoter region Activation of DNA repair enzymes, which may be prone to error Activation of telomerase Prevention of apoptosis Asbestos fibres have been shown to alter the function and secretory properties of macrophages, ultimately creating conditions which favour the development of mesothelioma. Following asbestos phagocytosis, macrophages generate increased amounts of hydroxyl radicals, which are normal by-products of cellular anaerobic metabolism. However, these free radicals are also known clastogenic and membrane-active agents thought to promote asbestos carcinogenicity. These oxidants can participate in the oncogenic process by directly and indirectly interacting with DNA, modifying membrane-associated cellular events, including oncogene activation and perturbation of cellular antioxidant defences. Asbestos also may possess immunosuppressive properties. For example, chrysotile fibres have been shown to depress the in vitro proliferation of phytohemagglutinin-stimulated peripheral blood lymphocytes, suppress natural killer cell lysis and significantly reduce lymphokine-activated killer cell viability and recovery. Furthermore, genetic alterations in asbestos-activated macrophages may result in the release of potent mesothelial cell mitogens such as platelet-derived growth factor (PDGF) and transforming growth factor-β (TGF-β) which in turn, may induce the chronic stimulation and proliferation of mesothelial cells after injury by asbestos fibres.

Staging

Mesothelioma is described as localized if the cancer is found only on the membrane surface where it originated. It is classified as advanced if it has spread beyond the original membrane surface to other parts of the body, such as the lymph nodes, lungs, chest wall, or abdominal organs.

Screening

There is no universally agreed protocol for screening people who have been exposed to asbestos. However some research indicates that the serum osteopontin level might be useful in screening asbestos-exposed people for mesothelioma. The level of soluble mesothelin-related protein is elevated in the serum of about 75% of patients at diagnosis and it has been suggested that it may be useful for screening

Pleural Mesothelioma - Information

There are two types of pleural mesothelioma: Diffuse & Malignant (cancerous) and localized and benign (non-cancerous). Malignant Pleural Mesothelioma is a cancer of cells making up the lining around the outside of the lungs and inside of the ribs. It is associated with asbestos (especially blue asbestos). Previous exposure to asbestos fibers including amosite, chrysotile or crocidolite asbestos is the only known cause to this disease. The exposure is likely to have happened 20 or more years before the disease would become evident. Is is the most common type of mesothelioma (accounting for about 75% of all cases). There are no blood tests available that are useful in diagnosing malignant mesothelioma. Benign Mesothelioma is often removed surgically and is generally not life threatening. It is usually not related to asbestos exposure however Malignant Mesothelioma is very serious and about 2,000 people are diagnosed with it in the United States each year. Some of the symptoms of Pleural Mesothelioma: Difficulty Sleeping Coughing Fever Fluid in chest cavities (Pleural effusions) Shortness of breath, difficulty breathing Trouble Swallowing Lower back and side of the chest pain Loss of weight and appetite

What is Pleural Mesothelioma? A malignant mesothelioma that spreads within a chest cavity and can sometimes involve the lung. In addition to Asbestos, some of the other factors that can promote this disease include: tuberculous pleuritis, chronic lung infections, radiation [Thorotrast] as well as exposure to Simian Virus 40 (SV40) or Zeolite which are mineral fibers. The combination of smoking and asbestos exposure greatly increase the risk of lung cancer even though tobacco smoking has not been associated with mesothelioma development. Mesothelioma is a rare cancer which affects specific membranes of the body. About three thousand new cases of mesothelioma are diagnosed each year. The primary cause of mesothelioma is exposure to asbestos and asbestos fibers. Due to the fact that the gestation period of mesothelioma can be 20 years or more, patients who are diagnosed have a poor prognosis. The most common type of mesothelioma is pleural mesothelioma (accounting for approximately 75% of all mesothelioma cases), or mesothelioma of the pleura.The pleura is a thin serous membrane that is found between the lungs and the chest cavity. It provides a lubricated surface so that the lungs do not chafe against the chest walls, while also serving as a protective layer. Pleural mesothelioma is often incorrectly labeled as a type of lung cancer because of the pleura's close proximity to the lungs. The second most common type of mesothelioma is peritoneal mesothelioma (accounting for approximately 10% to 20% of all mesothelioma cases), or mesothelioma of the peritoneum. The peritoneum is a slippery membrane that encloses the organs of the abdomen. While peritoneal mesothelioma is less common than pleural mesothelioma, it tends to be a more invasive form of the disease, yielding a shorter life expectancy for patients. The least common type of mesothelioma is pericardial mesothelioma (accounting for less than 10% of all mesothelioma cases), or mesothelioma of the pericardium. The pericardium is the membrane that surrounds and protects the heart; it is also referred to as the heart sac. The three most common forms of mesothelioma are: Pleural mesothelioma Peritoneal mesothelioma Pericardial mesothelioma The most common cause of mesothelioma is asbestos and exposure to asbestos fibers. Most mesothelioma can be traced to one or more exposures to asbestos. This has happened in the shipyard, construction and transportation industries. There are instances where second hand exposure of asbestos fibers has been responsible for the development of mesothelioma.

Who is at risk? People who are most at risk for developing mesothelioma are those working with asbestos. About 80% of this disease is associated with exposure to asbestos, however the disease has been reported in certain individuals without any known exposure to asbestos. It is more common in white Americans and affects men much more frequently than women. The median survival time is between four 4 to 12 months.

Mesothelioma (commonly mispelled: mesothilioma) is a rare type of cancer caused by exposure to asbestos. Below you will find lots of details and information on this rare disease. On the left you will find the navigation bar which will help guide you through the website. A rare and aggressive form of cancer, mesothelioma affects the inside lining of the abdomen and chest. The cells of the mesothelium (membrane covering and protecting internal organs) become abnormal forming tumors and growing without control or order. The disease is relatively uncommon with about 2,500 to 3,000 new cases diagnosed in the United States each year. People who usually develop this potentially deadly disease have had exposure to asbestos usually many years before. In fact, the symptoms may not even appear until 30 to 50 years after being exposed to asbestos. Chest pain and shortness of breath are typical symptoms of mesotheloma. If you have had a history of exposure to asbestos and develop those symptoms, you should seek medical attention. There are several types of treatment options available: Radiation, Surgery, and chemotherapy including recently approved medications. On our website you will find lots of treatment information and other asbestos related articles to help you gain a better understanding of this rare form of cancer

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.

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

Mesothelioma

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.