Mesothelioma Foundations and Charities

Mesothelioma foundations, like all non-profit organizations, rely heavily upon grants, bequests and other donations from individuals and organizations in order to achieve their mission.

The goals and methods of each individual mesothelioma foundation differ slightly - research for cures and treatments, public and patient education, patient support, legislative lobbying, or a combination – but overall they work for the same common goal: a cure.

The Mesothelioma Applied Research Foundation (MARF) focuses on:

• funding high quality and promising research projects internationally, chosen through peer review
• helping patients connect with mesothelioma experts and obtain information on cutting-edge treatment options
• advocating in Washington D.C. for federal mesothelioma research funding

MARF’s Board of Directors includes Dr. Nicholas J. Vogelzang, an oncologist and prior Director of the Nevada Cancer Institute, Dr. Jarl Ulf Jungnelius, oncologist and Vice President of Oncology, Solid Tumors at Celgene, and Ann Abbe, the Associate Vice President for Development at the University of North Texas and a 27-year veteran of nonprofits.

Their solid Science Advisory Board includes Dr. Harvey Pass, Professor of Surgery and Chief, Division of Thoracic Surgery and Thoracic Oncology at NYU School of Medicine and Comprehensive Cancer Center, Dr. Raffit Hassan, M.D., Investigator and Head, Mesothelin-Expressing Cancer Unit Laboratory of Molecular Biology, National Cancer Institute, a number of thoracic surgical oncologists with targeted expertise in treating mesothelioma patients, a professor of pathology at Duke University and Virginia Medical Centers, and a cancer geneticist.

In addition to mesothelioma patients and their families, the Foundation has successfully enlisted the financial aid of law firms, drug companies, and companies formerly involved with asbestos (one corporate donor is Owens Corning), an achievement that deserves recognition.

The Mesothelioma Research Foundation of America (MRFA) states its mission quite simply: fund research that will lead to the quickest cure for mesothelioma.

MRFA has been working toward that goal by funding clinical trial research at laboratories around the world. One such project, at the Mesothelioma Laboratory at the USC/Norris Comprehensive Cancer Center in Los Angeles, has yielded encouraging results with an angiogenesis drug called Veglin. Phase I results were reported to the American Society of Clinical Oncology, showing success in blocking tumor growth in patients suffering from lymphoma, sarcoma, Karposi's sarcoma and colon and lung cancers. In some instances, Veglin was successful in stabilizing and/or reducing previously untreatable malignant tumors. Phase II trials began in 2004.

MRFA’s Board is led by founding member Jerry Neil Paul, an asbestos litigation specialist with an insurance background and strong relationships with unions. Their Medical Advisory Board Dr. Jeffrey Scott, a medical oncologist with extensive clinical trial participation, Dr. Michael Koss, a Pulmonary and Mediastinal Pathologist and current Professor of Pathology at LAC/USC Medical Center, and Dr. Parkash Gill, head of the tumor and vascular biology laboratory at the University of Southern California, who has been supervising Veglin’s clinical trials.

In addition to donations from unions, law firms, and individuals in memory asbestos victims – MRFA’s Wall of Honor is a sobering reminder of the far-reaching impact of this disease – the organization hosts fund-raisers, such as Golf Invitationals and, earlier this year, the “Aim to Cure” shoot and Contra Costa County Sheriff’s Charity Ball.
The Asbestos Disease Awareness Organization (ADOA) is a “grassroots” group, founded by asbestos victims and their families. Focusing on victim’s rights to adequate research, treatment, fair compensation, and the right to file suit, their stated mission is to:

• Serve as the united voice for all asbestos victims
• Unite asbestos victims
• Educate the public and medical community about asbestos-related diseases
• Support research that leads to early detection, prevention and a cure
• Ensure equitable compensation for victims and their families
• Ban the use of asbestos

Because ADOA is an independent organization, with no financial or political ties to drug companies, law firms or asbestos-involved companies, the organization can promise that it will not be influenced by these entities. ADOA is funded exclusively through voluntary contributions and staffed by volunteers.

ADOA’s accomplishments from its inception in 2004 to date are impressive, with many international asbestos disease presentations, global conference participation, and Senate testimony sessions. ADOA has also developed videos, slide shows and written resources to promote public education and provide needed information to asbestos victims and their families.

As “grassroots” as the ADOA might be, and as voluntary as their staffing is, there is a star among the volunteers. Their Science Advisory Board includes Dr. Richard Lemen, former Assistant Surgeon General of the United States, retired Deputy and Acting Director of the National Institute for Occupational Safety and Health.

In addition to larger organizations such as MARF, MRFA and ADOA, smaller organizations, usually formed in memory of a victim, also struggle for a cure in their own way. Funds raised by these smaller groups are sometimes funneled into the larger foundations, although some have conceived more targeted, individual application of funds.

The Mark Buttitta Memorial Foundation for Research is one such organization. After Mark’s death in 2002, his family recognized a lack of funding for mesothelioma cure research, resulting from the disease’s low incidence and the vulnerable position of the disease’s victims – usually blue collar workers with limited political and lobbying power.

Although, as an advertising executive, Mark did not fit the typical demographic profile of mesothelioma victims, his family was compelled to join the fight by supporting research. Money raised through individual donations and fundraisers supports the groundwork necessary to apply for research grants. In this way, collective small donations become disproportionately effective. A recently approved generous grant for education and research from the National Institute for Health was partially made possible as a result of this dedicated Foundation.

Kati’s Hope was founded in 2005 by Kathleen Maloney, daughter and niece of asbestos fatalities and victim herself. Because her point of asbestos contact was through dust on her father’s clothing, the lymphoma she developed 40 years later was not attributed to asbestos exposure; biopsy results proved what she had immediately suspected.

Donations to Kati’s Hope go into their Breath Bank, which assists victims directly by defraying expenses not covered by insurance, and in some cases, personally; local volunteers will help victims and their families in their homes with tasks that they can no longer manage themselves.

Large or small, funded by government grants or individual donations, these organizations have recognized the acute need for supplementary mesothelioma research and education funding, and increased support for mesothelioma victims. Through their efforts, future victims may find their prognoses much brighter

Mesothelioma Facts & FAQs

What is mesothelioma?

Mesothelioma is a cancer of the cells that make up the lining around the outside of the lungs and inside of the ribs (pleura), or around the abdominal organs (peritoneum).

What does asbestos have to do with mesothelioma?

The only known cause of mesothelioma in the U.S. is previous exposure to asbestos fibers. Asbestos manufacturers knew about the hazards of asbestos seventy years ago - but they kept this knowledge to themselves. The first warnings to workers exposed to asbestos were given in the mid-1960s, and they were terribly inadequate. Even today, workers are not always told they are working around asbestos and are at risk for asbestos disease.

What can someone with mesothelioma do?

• Seek out the best and most up-to-date information.
• Seek out the best medical care.
• Early screening for mesothelioma diagnosis.
• Stay in close contact with your doctor.
• Consider whether or not you want to bring a lawsuit because of this asbestos-related injury.
• Remember that resources are available to you through community and medical support groups, asbestos victims' organizations, your place of worship, as well as your family and friends.

Mesothelioma: The Basics

What is mesothelial tissue?

The mesothelium is a protective sac that covers and protects most internal organs in the body. It is composed of two layers, one layer covers the organ and the second layer forms a sac around it. The mesothelium produces a lubricating fluid that is released between these layers, allowing moving organs (such as the lungs) to move easily. The area between the two layers is often called the pleural space. Mesothelial tissue is found lining the abdominal cavity organs, lungs, testes and heart.

What is mesothelioma?

Mesothelioma occurs when the mesothelial cells grow out of control. These cells also lose the ability to stop producing the lubricating fluid when there is enough. This results in the unwanted encasement of organs within a thick rind of tumor tissue and excess fluid build up, ultimately causing symptoms. These cells can grow and invade other organs, or spread to other areas of the body. When the cells spread to other areas of the body, it is called metastasis.

The majority of mesotheliomas are found in the lining of the lung (65-70%). About 20-30% percent of cases are found in the abdominal cavity lining, and even more rarely, mesothelioma is found in the lining of the heart (1-2%) or testicles.

Am I at risk for mesothelioma?

Mesothelioma is a rare cancer, with approximately 2,000 cases diagnosed each year in the United States. It is eight times more common in men, which is due in most part to work-related exposure to asbestos. Risk also increases with age. The biggest risk factor for developing the disease is exposure to asbestos, accounting for 70 to 80 percent of all cases. Asbestos has been used in many products, including cement, brake linings, roof shingles, flooring products, textiles, and insulation. Particles can be released from these products, particularly during the manufacturing process, and inhaled. Prior to knowing the dangers, asbestos miners and other workers exposed to asbestos worked without wearing any protection. Since the 1970's, the U.S. Occupational Safety and Health Administration (OSHA) has set limits for acceptable levels of asbestos exposure and requires protective equipment in the workplace. Family members of people who worked with asbestos were also exposed to the toxin when it was carried home on clothing and hair, putting them at increased risk for mesothelioma.

Eighty percent of cases of pleural mesothelioma occur in individuals who have had known asbestos exposure, yet only 10% of people with a history of heavy exposure develop the disease. This suggests that additional exposures or factors are involved to actually develop the disease. Even more puzzling is the fact that only 50% of people with peritoneal mesothelioma have a history of asbestos exposure.

It takes 20 to 40 years from the time of asbestos exposure until mesothelioma is detected. This exposure was usually over a period of time, but has been reported to be as little as one or two months of exposure. Smoking does not seem to increase the risk of developing the disease.

The incidence of mesothelioma varies in different areas of the world, depending on when asbestos was widely used in that area. Rates are higher in the United Kingdom, where about 1800 cases per year are diagnosed. The incidence takes into consideration the number of cases and the size of the population. This is because asbestos use in Western Europe remained high until 1980, whereas maximum exposure in the U.S. was from the 1930s to 1960s. Australia was one of the world’s largest producers of asbestos, leading to the country having the highest rates worldwide (based on the size of the population). Rates in the U.S. are beginning to decline, whereas rates in Europe and Australia are expected to plateau in the next 10-15 years before declining.

Following the ban of asbestos in many countries, asbestos producers started to promote the sale of their product to developing countries, such as Asia and Latin America. Experts fear that the peak rates in these areas are yet to come, and will mimic what has been seen in the U.S. and Europe.

Mesothelioma Risk Factors

In as many as 75-85% of mesothelioma cases, there is a history of exposure to asbestos. The material was used extensively in numerous industries from the early 1900’s through the 1960’s. Through the World War II era, over 8 million workers were exposed to asbestos. Evidence that serious health problems were related to asbestos began to mount, and in 1999, a conclusive link between asbestos exposure and mesothelioma was made.

Because it can take as long as 50 years for mesothelioma to develop, anyone who has been exposed should be evaluated by a physician experienced in this form of cancer. Even if you are not ill, you should learn about your legal rights in case mesothelioma is found in the future.

Asbestos is a broad term which refers to a collection of minerals know as asbestiform. It is a small mineral comprised of tiny fibers. Asbestos fibers exist in two forms; they can be either amphibole or serpentine (chrysotile). Several studies suggest that the amphibole form of asbestos is more dangerous than the chrysotile form, especially in mesothelioma.

These small particles float in the air, in an exposed environment and they may be inhaled or swallowed. Asbestos fibers breathed into the lungs cannot be expelled; they become embedded in the thin lining of the lungs, the mesothelium. Over the period of many years, cells in the mesothelium can become cancerous. In most cases of mesothelioma, it takes decades for the disease to cause symptoms.

Although a serious hazard to your health, asbestos is an excellent insulating material. It is used in many products that need to withstand high heat such as home insulation and construction, brake pads, electrical equipment, hot water piping, boilers, ship engines, and welding supplies. People who have worked in these industries should be screened regularly for the development of lung disease.

When the asbestos is contained within finished products such as walls and tiles, it does not appear to pose a health as long as it is not damaged or disturbed. However, damage or inadvertent destruction can release dangerous fibers into the air. When asbestos fibers are set free and inhaled, however, exposed individuals are at risk of developing an asbestos-related disease.

While smoking has not been found to cause mesothelioma, smoking has been linked to an increased incidence in mesothelioma in asbestos exposed workers. Therefore, if you have had occupational e exposure to asbestos, smoking could raise the risk of developing mesothelioma.

Asbestos exposure

The most common way in which people are exposed to asbestos is through their work. There are a number of jobs in which exposure to asbestos may have occurred. Asbestos has been extensively used in industrial products, including cement, brake linings, roof shingles, flooring products, textiles, and insulation as well as shipbuilding and other forms of construction. The risk of developing Mesothelioma increases according to the length and level of exposure to asbestos.

The number of workers exposed to asbestos far exceeds the number of documented cases. The reasons why some people who are exposed to asbestos do not develop the disease are not well understood.

The risk of developing asbestos-related diseases varies with the type of industry in which the exposure occurred and with the extent of the exposure. According to the Environmental Protection Agency (EPA) there is no safe level of exposure to asbestos fibers. The Occupational Safety and Health Administration (OSHA), however, has set a Permissible Exposure Limit (PEL) of 0.1 fibers per cubic centimeter (f/cc) for an 8 hour time weighted average. The safest course of action is to limit exposure and always wear protective gear when dealing with any type of suspected asbestos.

Hidden asbestos risks

The risk of developing mesothelioma is not just confined to the person directly exposed but may extend to family members and friends of those directly exposed. Even someone who has not been directly exposed or has been exposed at very low levels is at risk may develop the disease.

An increasing incidence of mesothelioma in spouses and children whose only to asbestos was from the dust laden work clothes of a family member is being reported. People who were in contact with workers in asbestos related injuries should also be vigilant for symptoms and be screened for lung disorders regularly.
Risk Factors Include:

* Automotive Mechanics
* Boilermakers
* Bricklayers
* Building Inspectors
* Carpenters
* Cement Finishers
* Drywallers
* Engineers
* Electricians
* Floor Coverings
* Welders
* Furnace Workers
* Glazers
* Grinders





* Hod carriers
* Insulators
* Iron Workers
* Labourers
* Longshoremen
* Machinists
* Maintenance workers
* Mechanics
* U.S. Navy veterans
* Merchant marines
* Metal Lathers
* Millwrights
* Operating Engineers
* Painters




* Pipefitters
* Plasterers
* Power Plant Workers
* Plumbers
* Railroad Workers
* Roofers
* Sand blasters
* Sawyers
* Sheet metal workers
* Shipyard Workers
* Steam fitters
* Tile setters
* Welders

Mesothelioma Stages

Doctors employ the use of “stages” in both cancer diagnoses and monitoring to determine the progress of an individuals’ disease. Staging takes a close look at cancers, like Mesothelioma, and determines to what extent it has developed and/or spread. Most importantly, staging helps determine the course of treatment.

Currently, though there are three types of Mesothelioma – pleural, peritoneal, and pericardial – staging has thus far been established for the most frequently occurring form of this cancer - pleural - and not for the others. The three systems that stage this disease are the Butchart, TNM, and Brigham systems.

Butchart is the oldest system and is still the most commonly used. Its four stages are based on the extent of primary tumor mass.

* Stage I: Mesothelioma is present in the right or left pleura (the thin, transparent membrane which covers the lungs and lines the inside of the chest walls) and may also involve the diaphragm (the muscle separating the chest from the abdomen) on the same side.
* Stage II: Mesothelioma invades the chest wall or involves the esophagus (food passage connecting the throat to the stomach, heart, or pleura on both sides. Lymph nodes in the chest may also be involved.
* Stage III: Mesothelioma has penetrated through the diaphragm into the lining of the abdominal cavity or peritoneum. Lymph nodes beyond those in the chest may now be affected as well.
* Stage IV: There is evidence of metastasis (the spreading of the Mesothelioma) through the bloodstream to other organs.

The TNM System looks at three components: the tumor (T), the lymph nodes (N), and the spreading of the disease, otherwise known as metastasis (M). It is also divided into four stages.

* Stage I: Mesothelioma involves right or left pleura and may also have spread to the lung, pericardium (the fluid filled sac that surrounds the heart), or diaphragm on the same side. Lymph nodes are not involved.
* Stage II: Mesothelioma has spread from the pleura on one side to nearby lymph nodes next to the lung on the same side. It may also have spread into the lung, pericardium, or diaphragm on the same side.
* Stage III: Mesothelioma has now invaded the chest wall, muscle, ribs, heart, esophagus, or other organs in the chest on the same side. It may or may not have spread to lymph nodes on the same side as the primary tumor.
* Stage IV: Mesothelioma has spread into the lymph nodes in the chest on the side opposite the primary tumor, or extends to the pleura or lung on the opposite side, or directly extends into organs in the abdominal cavity or neck. Any distant metastasis is included in this stage.

The most recent system to be devised is the Brigham System. It stages the disease according to the ability to surgically remove the tumor (resectability) and the involvement of the lymph nodes. It, too, is divided into four stages.

* Stage I: Mesothelioma is resectable and no lymph node involvement.
* Stage II: Mesothelioma is resectable but with lymph node involvement.
* Stage III: Presence of unresectable Mesothelioma extending into the chest wall, heart, or through the diaphragm or peritoneum; with or without extra-thoracic lymph node involvement.
* Stage IV: Distant metastatic disease (widespread cancer throughout the body).

Diagnosis is achieved in a number of ways, especially because other diseases may possess similar symptoms to those presented by Mesothelioma. A wide variety of imaging techniques may be used in diagnosis, such as CT scans, MRI, and conventional x-rays. Some doctors also choose to test the pleural fluid for malignant cells.

Biopsy, however, is by far the most accurate way to diagnose Mesothelioma. Needle biopsies, done under local anesthetic, may be used but provide only small tissue samples. That means the accuracy rate might be less than desirable. The preferred course of action in suspected Mesothelioma is an “open” biopsy, which provides a larger tissue sample. This type of biopsy is performed in a hospital setting under general anesthesia.

Do you suspect that you or someone close to you may be suffering from Mesothelioma or do you worry about a spouse or loved ones’ previous exposure to asbestos? Learn the facts about asbestos and the diseases it causes by ordering our free Mesothelioma Resource Kit.

Overview of Mesothelioma

If you or someone you know has been diagnosed with mesothelioma, you need all the information you can get about the illness and treatment options. This mesothelioma information will give you a better understanding of what the disease is, what causes it and how it is treated.

What is Mesothelioma?

Mesothelioma, or cancer of the mesothelium, is diagnosed in about 2,000 to 3,000 people in the United States each year, and is becoming more common over time.

The mesothelium is a type of tissue formed by cells that surround the chest cavity, abdominal cavity and heart cavity. It protects the organs of the body by producing a fluid that allows the organs to move, as the lungs must do during breathing.

The most common form of mesothelioma is known as pleural mesothelioma, which starts in the chest cavity. About 75 percent of all mesothelioma is of this type, while 10 percent to 20 percent starts in the abdomen (peritoneal mesothelioma). It is rare but not unknown to have a mesothelioma start in the heart cavity (pericardial mesothelioma) .

What Causes Mesothelioma?

Most people who develop mesothelioma get it because of exposure to asbestos, which is a general name given to groups of minerals that can be separated into durable threads. Asbestos is resistant to heat, fire and chemicals and does not conduct electricity, so it has been used in many construction projects and in other uses through the years .

A person's risk of developing mesothelioma varies depending on how much asbestos that person has been exposed to and for how long. Many people who develop mesothelioma do so later in life, but it has also been diagnosed in younger people and even in children.

Between 70 percent and 80 percent of all mesothelioma cases can be definitively traced back to asbestos exposure, and it is thought that the remainder are also asbestos-caused, but without an evidence trail to prove it. Many studies have looked at the links between mesothelioma and asbestos workers.

The death rate from mesothelioma in people who worked with asbestos insulation was 344 times higher than the death rate in the general population. Research indicates that within 15 years of initial exposure, about 6 percent of all asbestos workers over the age of 35 will die of the disease .

It is estimated that about 8 million Americans have been exposed to asbestos, either through occupational hazards, picking it up from the clothing of a family member or going to school or work in a building that contained asbestos. Its estimated that 10 percent to 15 percent of all public schools in America have asbestos in them - as many as 733,000 buildings .

Occupational exposure can come from working in the insulation, plumbing, electrical and construction industries, as well as from working with automotive brakes, boilers and in shipyards. People who do demolition work can also be exposed to asbestos, as well as people who live near asbestos factories or work in buildings where asbestos is present .

Most people don't contract mesothelioma until 30 to 45 years after their first exposure to asbestos, though the time between exposure and diagnosis can range from 10 to 65 years . This long latency period makes diagnosis more difficult, and also accounts for the continued incidence of mesothelioma even after asbestos became known as a threat; some patients who were exposed in 1960 are only now developing the disease. However, the incubation period is not always lengthy; particularly for children, it is possible to be exposed and become ill very quickly thereafter.

How does Asbestos Lead to Mesothelioma?

Asbestos is made of large numbers of tiny fibers that are easily inhaled by a person working with them. The body wants to break down and remove these foreign particles from the lungs, which causes inflammation.

The tiny asbestos particles can get into the smallest and most remote parts of the lungs and they can't be coughed out unless they stick to mucus in the air passages. They can also settle in the tissue around the chest cavity (pleura) or the stomach cavity (peritoneum), where they cause inflammation and lead to mesothelioma .

Asbestos fibers in the lungs can damage the organs by forming scar tissue, and the risk of lung cancer is seven times greater for people who have had asbestos exposure compared to people who have not had such exposure. In fact, the three main causes of death for people with intense asbestos exposure are this scarring of the lungs (also known as asbestosis), lung cancer and mesothelioma .

How is Mesothelioma Treated?

There are various factors that can impact how mesothelioma is treated, including what stage the cancer is in, the size of the tumor and whether it could be completely removed through surgery, the amount of fluid in the chest cavity, the type and location of the mesothelioma and the age and state of health of the patient .

Depending on all these factors, treatment can range from surgery to remove the tumor and some of the surrounding tissue, radiation therapy or chemotherapy, drug therapy or removal of part of the lung. There are many different combinations of treatments that are being used as part of clinical trials, including biologic therapy, which attempts to boost the immune system to prevent recurrences .

What are the Odds of Surviving Mesothelioma?

Mesothelioma is a very serious disease, with an average survival time of about one year after diagnosis. That's because it is often in a late stage by the time it is diagnosed. The rate of people with mesothelioma who are still alive five years after diagnosis is about 10 percent, but the rate is steadily increasing. Most doctors say the outlook is more favorable for people who are diagnosed today .

Working with a doctor who has experience treating mesothelioma, as well as getting as much mesothelioma information as you can, will go a long way toward giving you or your loved one the best possible prognosis.

Pathophysiology

Malignancies involving mesothelial cells that normally line the body cavities, including the pleura, peritoneum, pericardium, and testis, are known as malignant mesothelioma, which may be localized or diffuse. Most, but not all, cases of pleural malignant mesothelioma (MM [lung cancer]) are associated with asbestos exposure.¹ Of patients with pleural malignant mesothelioma, 77% have been exposed to asbestos in the past. Diagnosis is difficult because the results from fluid analysis of the effusion from the tumor are not usually diagnostic. Mesothelioma is more common in males than in females and it occurs most commonly in the fifth through seventh decades of life. Most cases (~90%) of malignant mesothelioma occur in the pleura.

The 3 major histological types of mesothelioma are sarcomatous, epithelial, and mixed. Pleural mesothelioma usually begins as discrete plaques and nodules that coalesce to produce a sheetlike neoplasm. Tumor growth usually begins at the lower part of the chest. The tumor may invade the diaphragm and encase the surface of the lung and interlobar fissures.

The tumor may also grow along drainage and thoracotomy tracts. As the disease progresses, it often extends into the pulmonary parenchyma, chest wall, and mediastinum. Pleural mesothelioma may extend into the esophagus, ribs, vertebra, brachial plexus, and superior vena cava.

Asbestos, amphibole asbestos, asbestos-crocidolite, and amosite asbestos in particular, is the principal carcinogen implicated in the pathogenesis. Exposure to chrysotile asbestos is associated with a lower incidence of mesothelioma. The industries associated with asbestos exposure include mining, ship building involving the use of asbestos, asbestos cement manufacture, ceramics, paper milling, auto parts (asbestos brake lining), railroad repair, and insulation. In Turkey, the use of the fibrous substance erionite (similar to amphibole asbestos) in building construction has led to an epidemic of pulmonary mesothelioma. Environmental exposure to asbestos in areas polluted by the substance may increase the incidence of mesothelioma.

Most malignant mesotheliomas have complex karyotypes, with extensive aneuploidy and rearrangement of many chromosomes. A loss of a single copy on chromosome 22 is the most common abnormality.

Frequency

United States

Approximately 2500-3000 cases are diagnosed per year. In the absence of occupational exposure to asbestos, the incidence is 0.1-0.2 per 100,000 population in both sexes. The risk is increased in polluted areas by 2- to 10-fold compared to nonpolluted areas. Of patients with malignant mesothelioma in the United States, 80% have been exposed to asbestos.

International

Incidence is 0.9 cases per 100,000 persons per year. Marked variability exists in the incidence of malignant mesothelioma in different countries. In some countries, the incidence is low even though asbestos exposure is high. The reasons for these differences are not known.

Mortality/Morbidity

• Median survival for patients with malignant mesothelioma is 11 months. It is almost always fatal. Median survival based on histologic type is 9.4 months for sarcomatous, 12.5 months for epithelial, and 11 months for mixed. Approximately 15% of patients have an indolent course.
• In a recent review of 64 patients undergoing pleurectomy the overall survival rate was 43%, 28%, and 10% at 1, 2, and 3 years, respectively. The overall median survival with epithelial histology was 21.7 months (n=56 patients), 5.8 months for sarcomatous or mixed type (n=28 patients, P=.0001). The causes of morbidity include atrial fibrillation, wound infection, prolonged intubation, pulmonary emboli, myocardial infarction, respiratory failure, deep vein thrombosis, and postoperative bleeding.
• Asbestos exposure is linked to at least 50% of patients developing malignant mesothelioma. Approximately 8 million people in the United States have been exposed to asbestos in the workplace. Family members are also exposed to asbestos embedded in the worker's clothing. Alcohol use, dietary factors, and smoking tobacco have no effect on the incidence of pleural mesothelioma.

Race

• Mesothelioma has no racial predilection. Asbestos exposure is the most important factor. Race is not a factor.

Sex

• Malignant mesothelioma is more common in men, with a male-to-female ratio of 3:1. It can also occur in children; however, these cases are not thought to be associated with asbestos exposure.
  • For women with mesothelioma, a 1996 case series by Ascoli et al showed 86% of tumors arising from the pleura, of which most were the epithelial type. Of the patients in this series, 75% had a history of exposure to asbestos and more than half developed the malignancy secondary to household contact with a worker exposed to asbestos.²
  • For men with mesothelioma, the same case series demonstrated 45.5% with a history of exposure to asbestos and 53% with occupational exposure to asbestos. Most who were involved were construction workers, railroad workers, naval mechanics, bakers, explosive workers, and automobile mechanics.²

Age

• Malignant mesothelioma has a peak incidence 35-45 years after asbestos exposure. Two-thirds of cases of malignant mesothelioma develop in the fifth to seventh decade of life.

Clinical History

• Dyspnea and nonpleuritic chest wall pain are the most common presenting symptoms of malignant mesothelioma. (Approximately 60-90% of patients have symptoms of chest pain or dyspnea.)
  • Chest radiographs show obliteration of the diaphragm, nodular thickening of the pleura, decreased size of the involved chest, radiolucent sheetlike encasement of the pleura, or a combination of these.
  • A loculated effusion is present in more than 50% of patients, and a major portion of the pleura is opacified by the effusion.
• Chest discomfort, pleuritic pain, easy fatigability, fever, sweats, and weight loss are the other common accompanying symptoms.
• Patients may also be asymptomatic, with evidence of a pleural effusion noted incidentally on physical examination or by chest radiograph.
• Metastatic disease is uncommon at presentation, and contralateral pleural abnormalities are usually secondary to asbestos-related pleural disease rather than metastatic disease.
• Despite the ban or reduction of asbestos in the 1960s, incidence of mesothelioma continues to increase because patients develop mesothelioma 20-40 years after asbestos exposure. The long latency period adds to the complexities of early diagnosis and treatment of the condition.

Physical

• In patients with malignant mesothelioma, physical findings of pleural effusion are usually noted upon percussion and auscultation.
• In rare cases, malignant mesothelioma manifests as cord compression, brachial plexopathy, Horner syndrome, or superior vena cava syndrome. Death is usually due to infection or respiratory failure from the progression of mesothelioma.
• Primary sites include the pleura (87%), the peritoneum (5.1%), the pericardium (0.4%), and the right side of the thorax (more so than the left side, by a right-to-left ratio of 1.6:1).

Causes

• A substantial proportion of patients were exposed to asbestos in asbestos mills, shipping yards, mines, or their homes.
• The crocidolite in asbestos is associated with mesothelioma in miners, manufacturers (using asbestos), and heating and construction workers. The rod-shaped amphiboles are more carcinogenic than the chrysotile.
• Malignant mesothelioma has also been linked to therapeutic radiation using thorium dioxide and zeolite, a silicate in the soil.
• An etiological role for simian virus 40 in malignant mesothelioma has also been suggested. Asbestos exposure alone was associated with malignant mesothelioma, but simian virus 40 alone was not; thus, some epidemiological evidence exists that simian virus 40 is a possible cocarcinogen. Its direct role at this point is still controversial.³
• Interleukin 8 has direct growth-potentiating activity in mesothelial cell lines.
• Loss of one copy of chromosome 22 is the single most common karyotypic change in malignant mesothelioma. Other chromosomal changes commonly observed include 1p, 3p, 9p, and 6q. Several changes in the tumor suppressor gene p16 (CDKN2A) and p14 (ARF) and loss of function of neurofibromin 2 (NF2) or merlin are altered

Asbestos Exposure: Who Is At Risk?

Asbestos was one of the most common industrial materials put to use in the twentieth century. It has also proven to be one of the most lethal, as inhaling asbestos fibers can lead to a wide range of pulmonary problems such as asthma and asbestosis - and can also be the direct cause of mesothelioma.

What is mesothelioma? It is a lethal cancer that attacks the membranes around the lungs, the heart and the abdominal cavity. Mesothelioma cancer of the lungs is by far the most common form. Perhaps its most unusual characteristic is that mesothelioma diagnosis usually occurs decades after the initial exposure to asbestos.

It takes years for the asbestos fibers to work their way into those membranes; after an extended presence they begin to cause fluid accumulation and tumor development. However the first mesothelioma symptoms are such afflictions as a persistent cough or shortness of breath - symptoms that are often mistaken for evidence of more common lung problems, which delays the mesothelioma diagnosis even further.

Expert Spotlight: Dr. Daniel Powers

Beginning in 1984, Dr. Powers has been a certified B-Reader providing individual case B-Reader interpretations, individual imaging work-ups (including chest x-rays, supine spiral CTs and prone HRCTs), large screening projects, and expert witness services.
Learn more about Dr. Powers...

Did you know that the first sign of asbestos exposure can be "water on the lung" (a pleural effusion - the pleura is a cellophane-like covering over the lungs - the visceral [organ] pleura [lining] and covering the chest cavity - the parietal [chest cavity] pleura [lining]). Unfortunately, most exposed workers never know they have such "water" accumulation. It can occur many times. In some of these patients the sticky "water" causes the linings of the lung and chest cavity to stick/fuse together. Read more about Pleural Effusion...