Monday, February 16, 2009

Mesothelioma Lawyer

Looking For a Mesothelioma Lawyer?

Please remember that it is very important to find a Mesothelioma Lawyer as quickly as possible after you have been diagnosed with Mesothelioma the reason being, there is a statue of limitation from state to state, which means there is a time limit set with regards to how long you have to take action after your diagnosis of mesothelioma, and if the time is to long, your chances may be lessened in winning your case. Take action now and contact professional lawyers..

Mesothelioma and Asbestos Exposure Research
A very important question to ask when looking for a Mesothelioma Lawyer is how expenses attorney fees will be handled for the case. The process of filing for a lawsuit for mesothelioma cancer is not something that will happen over night. Preparation for the trial and the trial itself will take many months or sometimes even years.

What is Mesothelioma

Mesothelioma is a rare neoplasm that arises from mesothelial cells lining the parietal anvisceral pleura and can present in a localized or diffuse manner. The localized variant (solitary fibrous tumor) is very uncommon and usually presents as a well-defined, encapsulated tumor that is not associated with exposure to asbestos. Typically, the lesions are diagnosed as an asymptomatic mass on a chest radiograph. Complete surgical resection is the treatment of choice.

The diffuse variant presents as a locally aggressive tumor commonly associated with asbestos exposure (75%).A long latency period between asbestos exposure and the development of the disease has been reported.Although smoking alone is not a reported risk factor, other factors such as radiation therapy and various occupational exposures have been implicated.In the late 1990s an association between simian virus 40 (SV 40) and mesothelioma was investigated.

The clinical presentation of a patient with diffuse malignant pleural mesothelioma (MPM) is variable; therefore, a thorough clinical evaluation is essential. Dyspnea secondary to pleural effusion or encasement of the lung and chest pain from tumor infiltration into the chest wall and

adjacent organs are the most commonly reported symptoms. Nonspecific symptoms such as weight loss, anorexia, night sweats, and weakness also frequently are noted. Physical signs vary depending on the stage of the neoplasm. Early in the disease, decreased breath sounds secondary to pleural effusion may be noted. In advanced stages of the disease, palpable tumor invading the chest wall and abdomen or nodal involvement may be identified. Radiographic tests such as chest radiography, chest CT, and MRI play a major role in the evaluation of the patient with mesothelioma.

Depending on the extent of disease, the chest radiographic findings may be quite variable. Typically, chest radiography demonstrates pleural thickening with or without pleural effusion. Chest CT and MRI are particularly effective in determining the presence of advanced disease, such as transdiaphragmatic involvement or mediastinal organ invasion.Echocardiography also is helpful in ruling out pericardial invasion. In the future, positron emission tomography (PET) also may prove to be a useful tool in determining the extent of tumor invasion.

A number of techniques are used to confirm the diagnosis of MPM, including thoracocentesis of pleural effusion and pleural biopsy (open, VATS, and closed).Open or VATS biopsy provides the best method to obtain a tumor sample sufficient to distinguish mesothelioma from other tumors such as adenocarcinoma and to determine the specific subtype of MPM. Frequently, immunohistochemistry techniques and electron microscopy performed by an experienced pathologist are required to confirm the diagnosis of MPM.

Microscopically, malignant mesothelioma originates from mesothelial cells that line the pleural cavity. Three histologic subtypes of mesothelioma have been identified; these are epithelial, sarcomatous, and mixed histologies.The histologic subtype has been shown to affect survival dramatically, with epithelial histology having a more favorable prognosis than the other two subtypes.

Diseases of the Lungs and Mesothelium

Mesothelioma is a rare disorder and is often misdiagnosed. It is a disease that derives directly from the mesothelial cells in the serous membranes. But it is not uncommon for other growths to appear in the mesothelium, both cancerous and non cancerous.

Tumors of the mesothelium can be benign (non-cancerous) or cancerous. A malignant tumor of the mesothelium is called malignant mesothelioma, but because most mesothelial tumors are cancerous, the disease is often simply called mesothelioma.

Benign Tumors

Although uncommon, the mesothelium of certain female and male reproductive organs may develop a benign tumor called an adenomatoid tumor. In men, the tumor starts in the area where the sperm is carried from the testicles and in women it starts in the fallopian tubes. Another type of benign tumor that starts in the female reproductive organs is called a benign cystic mesothelioma.

A type of benign tumor that used to be called benign fibrous mesothelioma can form in the pleura around the lungs. It is now known that this type of tumor starts in the tissues under the mesothelium and therefore is not a type of mesothelioma. It is typically not cancerous, but can progress to cancer in some cases. A similar disease that forms in the peritoneum is called a fibrous tumor of the peritoneum. These types of tumors are often removed surgically, and no other treatment is needed.

Malignant Tumors

The most common form of malignant tumors in the mesothelium are metastatic tumors. That is, the tumors start in another part of the body and then the cancer metastasizes and spreads to the mesothelium. The ratio is between 7: 1 to 20: 1 for the occurrence of these types of tumors versus a mesothelioma. Mesothelioma derives directly from the mesothelial cells and does not migrate into the mesothelium from other organs.

The most common metastatic tumors that grow in the pleura derive from, in descending order:

  • breast
  • lung
  • ovary
  • stomach
  • large intestine
  • pancreas
  • thyroid
  • kidney

For the pericardial tumors from metastases, the most common originating organs are lung, breast and thyroid. In the peritoneum, the ovary, stomach, large intestine, pancreas and breast are the most common sources of metastatic tumors.

Introduction of Mesothelioma

DEFINITION

Malignant mesothelioma is a rare neoplastic lesion associated with asbestos exposure. There are three major histologic subtypes: epithelial (most common), sarcomatous, and mixed (epithelial/sarcomatous).

EPIDEMIOLOGY & DEMOGRAPHICS

• Associated with asbestos exposure (all fiber types)
• Over 3000 new cases diagnosed in U.S. annually
• More common in men as a result of asbestos exposure in the workplace
• Right-sided involvement is more common
• Incidence of mesothelioma increases with age; median age at presentation is >60 yr
• There are currently more than 8 million persons in the U.S. who are at risk for mesothelioma because of prior asbestos exposure

thorotrast, zeolite, and erionite fibers.
PHYSICAL FINDINGS & CLINICAL PRESENTATION

• Dyspnea
• Nonpleuritic chest pain
• Fever, weight loss, sweats, fatigue, loss of appetite
• Dysphagia, superior vena cava syndrome, Horner’s syndrome in advanced stages
• Auscultation may reveal unilateral loss of breath sounds
• Dullness on percussion may be present

ETIOLOGY

• Asbestos exposure
• Other reported potentially causal factors include prior radiation therapy and extravasated

Epithelioid, Sarcomatoid and Biphasic Mesothelioma Cancer Cell Types

Epithelioid, Sarcomatoid and Biphasic Mesothelioma Cancer Cell Types

On this page:
» Epithelioid Mesothelioma
» Sarcomatoid Mesothelioma
» Biphasic Mesothelioma
» Mesothelioma Prognosis

Malignant mesothelioma is generally divided into three histological categories, or types of cells: epithelioid, sarcomatoid and biphasic mesothelioma. Within each of these mesothelioma cancer cell types, subtypes exist. Many mesothelioma patients display more than one cell type.

The diagnosis of mesothelioma cannot be specifically by lung x-rays or other types of imaging, because many different types of cancer can be present in the lungs. The images show only that a tumor may be present, but does not provide an indication of whether the tumor is mesothelioma. A biopsy must be performed where the mesothelioma cancer cell types are used to distinguish mesothelioma from other types of cancer, such as lung cancer.
Epithelioid Mesothelioma Cancer

Epithelioid mesothelioma is the most common cell type, constituting approximately 50% to 70% of all malignant mesothelioma. These cells are relatively uniform in shape and have a tubular pattern with a distinct cell nucleus. The individual cells are shaped like cubes or multi-sided boxes.

Because of the similarity between adenocarcinoma and mesothelioma cancer cells, they are often confused and mesothelioma can be misdiagnosed. Inspection of the cancer cells under high-powered microscopes and identification of unique characteristics of the chemical properties of the cells can help make the proper diagnosis. Learn more about epithelioid mesothelioma cancer.
Sarcomatoid Mesothelioma Cancer

Sarcomatoid mesothelioma is the least common type of mesothelioma cancer cell and accounts for approximately 10% to 15% of malignant mesothelioma. These cells typically have more of an oval, irregular shape and the nucleus of each cell is not as visible with a microscope as the epithelioid mesothelioma cancer cells. Because of the similarity of appearance, the sarcomatoid cancer cells can also easily be confused with the more typical sarcoma cancer cells. Learn more about sarcomatoid mesothelioma cancer.
Biphasic Mesothelioma Cancer

Approximately 20% to 40% of the mesothelioma cancer cells fall into the biphasic category, which is combination of the sarcomatoid and epithelioid types. The biphasic type can occur with the two types of cells intermixed continuously throughout the tumor, or with them in specific groupings. Transitional areas between the two cell types are often present. Learn more about biphasic mesothelioma cancer.
Prognosis Based on Cell Type

The mesothelioma cancer cell type does affect the prognosis. A study conducted on 167 patients showed that patients had the following mean survival times:
epithelioid ---- --8.5 months
sarcomatoid ---- 7 months
biphasic -------- 6 months

Treatment options are very similar for patients with the different cell types.

Mesothelioma Trials

Mesothelioma Trials

On this page:
» Clinical Trials
» Trial Phases

Mesothelioma is a relatively rare form of cancer linked to chronic asbestos exposure. There has been a sharp decline in asbestos exposure since the 1970s when asbestos use was halted for most applications. However, the incubation period for mesothelioma from initial exposure to asbestos to the onset of the disease varies from 20 to 50 years. As such, deaths related to this disease have risen recently and are expected to continue rising until the year 2020. This anticipated increase in incidence of mesothelioma has spurred considerable interest in clinical trials to develop better treatments for the deadly disease.

Mesothelioma Clinical Trials


Until recently, clinical trials for mesothelioma were difficult to conduct. The disease had a rapid onset and progression, leading to a relatively short survival period in which to conduct clinical trials. Also, there was a lack of basic understanding about the clinical biology of the disease and how the disease changed during progression.

Specific clinical measures were difficult to obtain in order to demonstrate the response to treatment. Recently, as part of the Alimta clinical trial, researchers developed new metrics that included factors other than just pleural thickening or abnormal breathing capability. A number of new clinical trials are now underway, many of them using these new measurement techniques. Hopefully these trials will lead to ways to stop or reverse the progression of mesothelioma.

Mesothelioma Trial Phases


Clinical trials for evaluating mesothelioma treatments are broken into four parts or phases. These Phases are described below (Source FDA).

Phase I
Researchers evaluate a drug or treatment in a small group of people/patients (20 to 80) for the first time to evaluate a drug's safety, determine the appropriate dosage range and identify side effects.

Phase II
Researchers treat a larger group of people/patients to determine if the drug treatment is effective and safe for the dosage levels determined in Phase I.

Phase III
Researchers administer the drug or treatment to a large group of people/patients to confirm the effectiveness of the drug and evaluate the drug's side effects. In this phase, the drug under evaluation will be compared to commonly used treatments. Additionally, researchers use Phase III trials to determine the proper protocol for the use of the drug when it is released for routine treatment.

Phase IV
Researchers perform follow-up studies from Phase III, primarily to obtain information that can be used when marketing the drug, such as drug risks, benefits and optimum use.

Types of Mesothelioma

Mesothelioma cancer affects the serous membranes that surround the major organs in the midsection of the body. Different organs can be affected by mesothelioma because the serous membranes surround the lungs, heart, abdomen and others. The most common type of mesothelioma is that which affects the lung lining, and is called pleural mesothelioma. Other types are pericardial mesothelioma, which affects the lining of the heart, and peritoneal mesothelioma, affecting the lining of the abdomen.

Mesothelioma, contrary to what many people think, is not a type of primary lung cancer. That is, mesothelioma does not originate in the lungs, but as described above, it starts in the serous membranes or lining around the lungs (or other organs). However, mesothelioma can spread to the lungs and when this occurs, it is considered to be a secondary lung cancer. Mesothelioma is also commonly referred to as an asbestos lung cancer. Technically, this is also incorrect, since mesothelioma does not originate in the lungs. Asbestosis is a type of asbestos lung disease that is often confused with mesothelioma.

Pleural Mesothelioma

Pleural mesothelioma represents about 75% of all mesotheliomas. The disease can grow quickly and enlarge the pleural space, causing it to fill with fluid. This fluid leads to the discomfort or pain associated with first detection of the disease. It is thought that pleural mesothelioma is caused by the inhaling of fibrous materials, including asbestos. These fibers lodge in the pleura and, over time, cause damage to the tissue layer and cancer erupts. Learn more about pleural mesothelioma.

Pericardial Mesothelioma

The rarest form of mesothelioma is that which affects the linings of the heart cavity, called the pericardium. Less than 10% of all mesothelioma cases are related to the heart. As in the lung, the rapid growth of the cancerous tumors can cause expansion of the tissue and accumulation of fluid. The fluid can interfere with the functioning of the heart and cause chest pain. Mesothelioma cases are known to be caused by exposure to asbestos; but it is completely unknown how the asbestos fibers enter the tissue layers surrounding the heart. Learn more about pericardial mesothelioma.

Peritoneal Mesothelioma

Mesothelioma of the abdomen is called peritoneal mesothelioma. The serous membrane surrounding the abdomen is known as the peritoneum. This disease accounts for approximately 10% to 20% of mesothelioma cases. In addition, a rare form of peritoneal mesothelioma affects the male testicles. The covering layer of the scrotum is actually an outpouching of the peritoneum. Peritoneal mesothelioma is due to the ingestion of fibrous materials, including asbestos. Learn more about peritoneal mesothelioma.

Mesothelioma Symptoms

Mesothelioma symptoms are not specific to the disease; that is, many mesothelioma symptoms are also symptoms of other medical problems.Most studies show that the symptoms of mesotheliomausually begin to appear 30 to 40 years after exposure to asbestos. Thus, many mesothelioma patients are unaware that the symptoms they are experiencing are related to something that happened much earlier in their lives. Even a short period of asbestos exposure (as little as a few months) can create the conditions for a disease that erupts much later in life.

Mesothelioma affects the lining of various cavities in the body. Over time, the growth of cancerous tumors causes these tissues to expand and gather fluid. The presence of excess fluid is typically what causes the symptoms to occur. Mesothelioma symptoms also depend on the location of the tumors.
Pleural Mesothelioma Symptoms

For pleural mesothelioma, or mesothelioma of the lining surrounding the lung, common symptoms include shortness of breath, chest pain and a persistent cough. Unfortunately, these symptoms are also very common for a number of other ailments, including pneumonia. The most common symptom is localized chest pain, but this may not occur until the disease is well advanced. A less common but still prevalent symptom of pleural mesothelioma is weight loss. Some patients show virtually no symptoms.
Peritoneal Mesothelioma Symptoms

Peritoneal mesothelioma is a cancer of the abdominal lining. Symptoms include swelling or a mass in the abdomen, weight loss and abdominal pain. Bowel obstruction and blood clots also have been known to occur and fever is sometimes present.
Pericardial Mesothelioma Symptoms

Pericardial mesothelioma affects the lining of the heart, or pericardium. Symptoms include chest pain, cough, irregular heart beat and irregular breathing patterns. Many of these symptoms manifest during physical exertion – even minimal exertion. Pericardial mesothelioma is the rarest type of mesothelioma.

The earlier cancer is detected – mesothelioma or otherwise – the more effective treatment aimed at halting its progression will be.

Mesothelioma: Questions and Answers

Mesothelioma is a rare form of cancer in which malignant (cancerous) cells are found in the mesothelium, a protective sac that covers most of the body's internal organs. Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles.

  1. What is the mesothelium?
  2. The mesothelium is a membrane that covers and protects most of the internal organs of the body. It is composed of two layers of cells: One layer immediately surrounds the organ; the other forms a sac around it. The mesothelium produces a lubricating fluid that is released between these layers, allowing moving organs (such as the beating heart and the expanding and contracting lungs) to glide easily against adjacent structures.

    The mesothelium has different names, depending on its location in the body. The peritoneum is the mesothelial tissue that covers most of the organs in the abdominal cavity. The pleura is the membrane that surrounds the lungs and lines the wall of the chest cavity. The pericardium covers and protects the heart. The mesothelial tissue surrounding the male internal reproductive organs is called the tunica vaginalis testis. The tunica serosa uteri covers the internal reproductive organs in women.

  3. What is mesothelioma?
  4. Mesothelioma (cancer of the mesothelium) is a disease in which cells of the mesothelium become abnormal and divide without control or order. They can invade and damage nearby tissues and organs. Cancer cells can also metastasize (spread) from their original site to other parts of the body. Most cases of mesothelioma begin in the pleura or peritoneum.

  5. How common is mesothelioma?
  6. Although reported incidence rates have increased in the past 20 years, mesothelioma is still a relatively rare cancer. About 2,000 new cases of mesothelioma are diagnosed in the United States each year. Mesothelioma occurs more often in men than in women and risk increases with age, but this disease can appear in either men or women at any age.

  7. What are the risk factors for mesothelioma?
  8. Working with asbestos is the major risk factor for mesothelioma. A history of asbestos exposure at work is reported in about 70 percent to 80 percent of all cases. However, mesothelioma has been reported in some individuals without any known exposure to asbestos.

    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.

    Smoking does not appear to increase the risk of mesothelioma. However, the combination of smoking and asbestos exposure significantly increases a person's risk of developing cancer of the air passageways in the lung.

  9. Who is at increased risk for developing mesothelioma?
  10. Asbestos has been mined and used commercially since 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 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. People who work with asbestos wear personal protective equipment to lower their risk of exposure.

    The risk of asbestos-related disease increases with heavier exposure to asbestos and longer exposure time. However, some individuals with only brief exposures have developed mesothelioma. On the other hand, not all workers who are heavily exposed develop asbestos-related diseases.

    There is some evidence that 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 fibers, asbestos workers are usually required to shower and change their clothing before leaving the workplace.

  11. What are the symptoms of mesothelioma?
  12. Symptoms of mesothelioma may not appear until 30 to 50 years after exposure to asbestos. Shortness of breath and pain in the chest due to an accumulation of fluid in the pleura are often symptoms of pleural mesothelioma. Symptoms of peritoneal mesothelioma include weight loss and abdominal pain and swelling due to a buildup of fluid in the abdomen. 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. It is important to see a doctor about any of these symptoms. Only a doctor can make a diagnosis.

  13. How is mesothelioma diagnosed?
  14. 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, including any history of asbestos exposure. A complete physical examination may be performed, including x-rays of the chest or abdomen and lung function tests. A CT (or CAT) scan or an MRI may also be useful. A CT scan is a series of detailed pictures of areas inside the body created by a computer linked to an x-ray machine. In an MRI, a powerful magnet linked to a computer is used to make detailed pictures of areas inside the body. These pictures are viewed on a monitor and can also be printed.

    A biopsy is needed to confirm a diagnosis of mesothelioma. In a biopsy, a surgeon or a medical oncologist (a doctor who specializes in diagnosing and treating cancer) 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 peritoneoscopy. To obtain tissue for examination, the doctor makes a small opening in the abdomen and inserts a special instrument called a peritoneoscope into the abdominal cavity. If these procedures do not yield enough tissue, more extensive diagnostic surgery may be necessary.

    If the diagnosis is mesothelioma, the doctor will want to learn the stage (or extent) of the disease. Staging involves more tests in a careful attempt to find out whether the cancer has spread and, if so, to which parts of the body. Knowing the stage of the disease helps the doctor plan treatment.

    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.

  15. How is mesothelioma treated?
  16. Treatment for mesothelioma depends on the location of the cancer, the stage of the disease, and the patient's age and general health. Standard treatment options include surgery, radiation therapy, and chemotherapy. Sometimes, these treatments are combined.

    • Surgery is a common treatment for mesothelioma. The doctor may remove part of the lining of the chest or abdomen and some of the tissue around it. For cancer of the pleura (pleural mesothelioma), a lung may be removed in an operation called a pneumonectomy. Sometimes part of the diaphragm, the muscle below the lungs that helps with breathing, is also removed.
    • Radiation therapy, also called radiotherapy, involves the use of high-energy rays to kill cancer cells and shrink tumors. Radiation therapy affects the cancer cells only in the treated area. The radiation may come from a machine (external radiation) or from putting materials that produce radiation through thin plastic tubes into the area where the cancer cells are found (internal radiation therapy).
    • Chemotherapy is the use of anticancer drugs to kill cancer cells throughout the body. Most drugs used to treat mesothelioma are given by injection into a vein (intravenous, or IV). Doctors are also studying the effectiveness of putting chemotherapy directly into the chest or abdomen (intracavitary chemotherapy).

    To relieve symptoms and control pain, the doctor may use a needle or a thin tube to drain fluid that has built up in the chest or abdomen. The procedure for removing fluid from the chest is called thoracentesis. Removal of fluid from the abdomen is called paracentesis. Drugs may be given through a tube in the chest to prevent more fluid from accumulating. Radiation therapy and surgery may also be helpful in relieving symptoms.

  17. Are new treatments for mesothelioma being studied?
  18. Yes. Because mesothelioma is very hard to control, the National Cancer Institute (NCI) is sponsoring clinical trials (research studies with people) that are designed to find new treatments and better ways to use current treatments. Before any new treatment can be recommended for general use, doctors conduct clinical trials to find out whether the treatment is safe for patients and effective against the disease. Participation in clinical trials is an important treatment option for many patients with mesothelioma.

    People interested in taking part in a clinical trial should talk with their doctor. Information about clinical trials is available from the Cancer Information Service (CIS) (see below) at 1–800–4–CANCER. Information specialists at the CIS use PDQ®, NCI's cancer information database, to identify and provide detailed information about specific ongoing clinical trials. Patients also have the option of searching for clinical trials on their own. The clinical trials page on the NCI's Cancer.gov Web site, located at http://www.cancer.gov/clinicaltrials on the Internet, provides general information about clinical trials and links to PDQ.

    People considering clinical trials may be interested in the NCI booklet Taking Part in Cancer Treatment Research Studies. This booklet describes how research studies are carried out and explains their possible benefits and risks. The booklet is available by calling the CIS, or from the NCI Publications Locator Web site at http://www.cancer.gov/publications on the Internet.

Veterans and Mesothelioma

Thousands of men and women who served our county from World War II to Vietnam are sick from asbestos exposure during their military service. Asbestos was often used for a number of military purposes especially construction and ship-building. Due to long latency periods, people who served as far back as the Second World War are only now being diagnosed.

While a diagnosis of mesothelioma is bad enough, veterans lack the same rights as civilians when it comes to compensation for their exposure.

According to "sovereign immunity," compensation cannot be sought from their former employer, the federal government. The only legal path for veterans is to try and find companies that were involved in providing or installing the asbestos to which they were exposed. However given the amount of time that has elapsed, most of those potential plaintiffs are out of business or involved in bankruptcy proceedings, making it difficult to receive compensation.

More information on mesothelioma can be found at MesotheliomaWeb

Legal History of Mesothelioma

The first lawsuit against asbestos manufacturers was brought in 1929. The parties settled that lawsuit, and as part of the agreement, the attorneys agreed not to pursue further cases. It was not until 1960 that an article published by Wagner et al first officially established mesothelioma as a disease arising from exposure to crocidolite asbestos.[22] The article referred to over 30 case studies of people who had suffered from mesothelioma in South Africa. Some exposures were transient and some were mine workers. In 1962 McNulty reported the first diagnosed case of malignant mesothelioma in an Australian asbestos worker.[23] The worker had worked in the mill at the asbestos mine in Wittenoom from 1948 to 1950.

In the town of Wittenoom, asbestos-containing mine waste was used to cover schoolyards and playgrounds. In 1965 an article in the British Journal of Industrial Medicine established that people who lived in the neighbourhoods of asbestos factories and mines, but did not work in them, had contracted mesothelioma.

Despite proof that the dust associated with asbestos mining and milling causes asbestos related disease, mining began at Wittenoom in 1943 and continued until 1966. In 1974 the first public warnings of the dangers of blue asbestos were published in a cover story called "Is this Killer in Your Home?" in Australia's Bulletin magazine. In 1978 the Western Australian Government decided to phase out the town of Wittenoom, following the publication of a Health Dept. booklet, "The Health Hazard at Wittenoom", containing the results of air sampling and an appraisal of worldwide medical information.

By 1979 the first writs for negligence related to Wittenoom were issued against CSR and its subsidiary ABA, and the Asbestos Diseases Society was formed to represent the Wittenoom victims.

Treatment of Mesothelioma


Treatment of malignant mesothelioma using conventional therapies in combination with radiation and or chemotherapy on stage I or II Mesothelioma have proved on average 74.6 percent successful in extending the patients life span by five years or more [commonly known as remission][this percentage may increases or decrease depending on date of discovery / stage of malignant development] (Oncology Today, 2009). Treatment course is primarily determined by the staging or development. This is unlike traditional treatment such as surgery by itself which has proved only be 16.3 percent likely to extend a patients life span by five years or more [commonly known as remission]. Clinical behavior of the malignancy is affected by several factors including the continuous mesothelial surface of the pleural cavity which favors 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, by itself, has proved disappointing. However, research indiates varied success when used in combination with radation and cheemotherapy (Duke, 2008) 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.

RadiationSister project

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.[12] 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. In January 2009, the United States FDA approved using conventional therapies such as surgery in combination with radiation and or chemotherapy on stage I or II Mesothelioma after research conducted by a nationwide study by Duke University concluded an almost 50 point increase in remission rates.

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.[13] 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.

Epidemiology of Mesothelioma

Incidence

Although reported incidence rates have increased in the past 20 years, mesothelioma is still a relatively rare cancer. The incidence rate is approximately one per 1,000,000. The highest incidence is found in Britain, Australia and Belgium: 30 per 1,000,000 per year.[7] For comparison, populations with high levels of smoking can have a lung cancer incidence of over 1,000 per 1,000,000. Incidence of malignant mesothelioma currently ranges from about 7 to 40 per 1,000,000 in industrialized Western nations, depending on the amount of asbestos exposure of the populations during the past several decades.[8] It has been estimated that incidence may have peaked at 15 per 1,000,000 in the United States in 2004. Incidence is expected to continue increasing in other parts of the world. Mesothelioma occurs more often in men than in women and risk increases with age, but this disease can appear in either men or women at any age. Approximately one fifth to one third of all mesotheliomas are peritoneal.

Between 1940 and 1979, approximately 27.5 million people were occupationally exposed to asbestos in the United States [4]. Between 1973 and 1984, there has been a threefold increase in the diagnosis of pleural mesothelioma in Caucasian males. From 1980 to the late 1990s, the death rate from mesothelioma in the USA increased from 2,000 per year to 3,000, with men four times more likely to acquire it than women. These rates may not be accurate, since it is possible that many cases of mesothelioma are misdiagnosed as adenocarcinoma of the lung, which is difficult to differentiate from mesothelioma.

Risk factors

Working with asbestos is the major risk factor for mesothelioma.[9] 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.[10]

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. Recent findings have shown that a mineral called erionite has been known to cause genetically pre-dispositioned individuals to have malignant mesothelioma rates much higher than those not pre-dispositioned genetically. A study in Cappadocia, Turkey has shown that 3 villiages in Turkey have death rates of 51% attributed to erionite related mesothelioma.

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.

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 exposures

Incidence of mesothelioma had been found to be higher in populations living near naturally occurring asbestos. For example, in Cappadocia, Turkey, an unprecedented mesothelioma epidemic caused 50% of all deaths in three small villages. Initially, this was attributed to erionite, however, recently, it has been shown that erionite causes mesothelioma mostly in families with a genetic predisposition

Pathophysiology of Mesothelioma

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).[6] However, there is now evidence that smaller particles may be more dangerous than the larger fibers.[1][2] 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.[3]

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 fibers 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.


Diagnosis of Mesothelioma


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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 incision 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.

Typical immunohistochemistry results
Positive Negative
EMA (epithelial membrane antigen) in a membranous distribution CEA (carcinoembryonic antigen)
WT1 (Wilms' tumour 1) B72.3
Calretinin MOC-3 1
Mesothelin-1 CD15
Cytokeratin 5/6 Ber-EP4
HBME-1 (human mesothelial cell 1) TTF-1 (thyroid transcription factor-1)

Signs and symptoms of Mesothelioma

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 (hemoptysis)

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.

Basic introduction of Mesothelioma


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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 internal chest wall), but it may also occur in the peritoneum (the lining of the abdominal cavity), the heart,[1] the pericardium (a sac that surrounds the heart) or tunica vaginalis.

Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles, or they have been exposed to asbestos dust and fiber in other ways. Washing the clothes of a family member who worked with asbestos can also put a person at risk for developing mesothelioma.[2] Unlike lung cancer, there is no association between mesothelioma and smoking.[3] Compensation via asbestos funds or lawsuits is an important issue in mesothelioma (see asbestos and the law).

The symptoms of mesothelioma include shortness of breath due to pleural effusion (fluid between the lung and the chest wall) or chest wall pain, and general symptoms such as weight loss. The diagnosis may be suspected with chest X-ray and CT scan, and is confirmed with a biopsy (tissue sample) and microscopic examination. A thoracoscopy (inserting a tube with a camera into the chest) can be used to take biopsies. It allows the introduction of substances such as talc to obliterate the pleural space (called pleurodesis), which prevents more fluid from accumulating and pressing on the lung. Despite treatment with chemotherapy, radiation therapy or sometimes surgery, the disease carries a poor prognosis. Research about screening tests for the early detection of mesothelioma is ongoing.