samedi 25 mai 2013

ASBESTOS


workers in PPE
"Asbestos" is a commercial name, not a mineralogical definition, given to a variety of six naturally occurring fibrous minerals. These minerals possess high tensile strength, flexibility, resistance to chemical and thermal degradation, and electrical resistance. These minerals have been used for decades in thousands of commercial products, such as insulation and fireproofing materials, automotive brakes and textile products, and cement and wallboard materials.
When handled, asbestos can separate into microscopic-size particles that remain in the air and are easily inhaled. Persons occupationally exposed to asbestos have developed several types of life-threatening diseases, including asbestosis, lung cancer and mesothelioma. Although the use of asbestos and asbestos products has dramatically decreased in recent years, they are still found in many residential and commercial settings and continue to pose a health risk to workers and others.

NIOSHTIC-2 Search

NIOSHTIC-2 Search Results on Asbestos
NIOSHTIC-2 is a searchable bibliographic database of occupational safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.

Recommendations for Preventing Occupational Exposure to Asbestos

Asbestos Fibers and Other Elongate Mineral Particles: State of the Science and Roadmap for Research
DHHS (NIOSH) Publication Number 2011-159 (March 2011)
This document is intended as one step in the process. NIOSH intends to pursue partnerships with other federal agencies and stakeholders to help focus the scope of the research that can contribute to the scientific understanding of asbestos and other mineral fibers, to fund and conduct the research activities, and to develop and disseminate educational materials describing results from the mineral fiber research and their implications for occupational and public health policies and practices.
Draft Document for Public Review and Comment: Asbestos and Other Mineral Fibers: A Roadmap for Scientific Research
This NIOSH Docket Archive contains all draft versions, comments on the draft documents and NIOSH responses and other materials that contributed to the development of the final publication.
NIOSH Recommendations for Limiting Potential Exposures of Workers to Asbestos Associated with Vermiculite from Libby, Montana
DHHS (NIOSH) Publication Number 2003-141 (2003)
Fact Sheet describes Vermiculite and Asbestos, and provides recommendations to prevent occupational exposures.
Asbestos Bibliography (Revised)
DHHS (NIOSH) Publication No. 97-162 (1997)
Compendium of NIOSH research and recommendations on asbestos. It updates and supersedes the NIOSH document Asbestos Publications from June 1992.
Occupational Health Guidelines for Chemical Hazards
DHHS (NIOSH) Publication No. 81-123 (January 1981)
Guidelines summarize pertinent information about chemical hazards for workers, employers, and occupational safety and health professionals.
Specific Medical Tests for OSHA Regulated Substances: Asbestos
Control of Asbestos Exposure During Brake Drum Service
DHHS (NIOSH) Publication No. 89-121 (1989)
Presents recommendations for engineering controls and work practices to reduce exposure to asbestos during brake maintenance operations, more...
Workplace Exposure to Asbestos: Review and Recommendations: NIOSH/OSHA Asbestos Work Group Recommendations
DHHS (NIOSH) Publication No. 81-103 (1980)
PDF only Adobe PDF file 2285 KB (41 pages)
Includes information about sampling and analysis of airborne asbestos, biologic effects of exposure, recommended occupational standards, more...
Current Intelligence Bulletin #31 – Adverse Health Effects of Smoking and the Occupational Environment
DHHS (NIOSH) Publication No 79-122 (1979)
Identifies six ways in which smoking can interact with workplace exposures, including asbestos.
Revised Recommended Asbestos Standard
DHHS (NIOSH) Publication No. 77-169 (1976)
Review of information on the health effects of exposure to asbestos.
Criteria for a Recommended Standard – Occupational Exposure to Asbestos
DHHS (NIOSH) Publication No. 72-10267 (1972)
Presents the criteria and standards for preventing occupational diseases arising from exposure to asbestos dust.

Asbestos Abatement

An Evaluation of Glove Bag Containment in Asbestos Removal
NIOSH Publication No. 90-119 (1990)
Examines the effectiveness of the glove bag control method to prevent asbestos emissions during the removal of asbestos-containing pipe lagging.

B-Reader Program

NIOSH B-Reader Program>
NIOSH B-Reader approval is granted to physicians who demonstrate proficiency in the classification of chest x-rays for the pneumoconioses using the International Labour Office (ILO) Classification System.

Conference Proceedings

Proceedings of the VIIth International Pneumoconioses Conference Part I
NIOSH Publication No. 90-108 Part I (1990)
Proceedings of the VIIth International Pneumoconioses Conference Part II
NIOSH Publication No. 90-108 Part II (1990)

Home Contamination

Protecting Workers' Families: A Research Agenda: Report of the Workers' Family Protection Task Force
DHHS (NIOSH) Publication No. 2002-113 (2002)
Represents the Task Force's commentary on the 1995 NIOSH Workers' Home Contamination Study report, identifies gaps in the current knowledge about take-home exposures and related health effects, and provides a prioritized agenda for Federally sponsored research.
Protect Your Family: Reduce Contamination at Home
DHHS (NIOSH) Publication No. 97-125 (1997)
This report summarizes a NIOSH conducted a study of contamination of workers' homes by hazardous substances transported from the workplace.
Report to Congress on Workers' Home Contamination Study Conducted Under the Workers' Family Protection Act (29 U.S.C. 671A)>
DHHS (NIOSH) Publication No. 95-123 (September 1995)—Summary
This report to Congress and the Workers' Family Protection Task Force summarizes incidents of home contamination, including the health consequences, sources, and levels of contamination.

Sampling and Analysis

NIOSH Manual of Analytical Methods (NMAM), 4th edition
DHHS (NIOSH) Publication No. 94-113 (1994)
NMAM is a collection of methods for sampling and analysis of contaminants in workplace air, and in the blood and urine of workers who are occupationally exposed. These methods have been developed or adapted by NIOSH or its partners and have been evaluated according to established experimental protocols and performance criteria. NMAM also includes chapters on quality assurance, sampling, portable instrumentation, etc.
  • Method #7400 - Asbestos and Other Fibers by PCM
    PDF only Adobe PDF file  140 KB (15 pages)  
  • Method #7402 - Asbestos by TEM
    PDF only Adobe PDF file   37 KB (7 pages)  
  • Method #9000 - Asbestos, Chrysotile by XRD
    PDF only Adobe PDF file   42 KB (6 pages)  
  • Method #9002 - Asbestos (bulk) by PLM
    PDF only Adobe PDF file   175 KB (9 pages)  
NIOSH Pocket Guide to Chemical Hazards
DHHS (NIOSH) Publication No. 97-140
Exposure limits, Respirator Recommendations, First Aid, more...
The Pocket Guide is a source of general industrial hygiene information on several hundred chemicals/classes found in the work environment. Key data provided for each chemical/substance includes name (including synonyms/trade names), structure/formula, CAS/RTECS Numbers, DOT ID, conversion factors, exposure limits, IDLH, chemical and physical properties, measurement methods, personal protection, respirator recommendations, symptoms, and first aid.

Worker Notification Program

Through the NIOSH Worker Notification Program, NIOSH notifies workers and other stakeholders about the findings of past research studies related to a wide variety of exposures. The link below presents archival materials sent to participants in a study at an asbestos textile, friction, and packing plant who were exposed to asbestos.

Surveillance

Occupational Respiratory Disease Surveillance (ORDS)
NIOSH Topic Page about occupational respiratory disease medical screening and monitoring.
Atlas of Respiratory Disease Mortality, United States: 1982-1993
DHHS (NIOSH) Publication No. 98-157 (1998)
This report presents maps showing geographic distributions (by health service area) of mortality associated with selected respiratory conditions that together represent nearly all respiratory diseases. For categories of traditional occupational lung diseases mapped in this atlas (i.e., the pneumoconioses, including coal workers’ pneumoconiosis, asbestosis, silicosis, byssinosis, and other and unspecified pneumoconioses), nearly all cases are attributable to hazardous occupational exposure.
Worker Health Chartbook, 2000
DHHS (NIOSH) Publication No. 2000-127 (2000)
The Worker Health Chartbook presents data and charts that characterize types of injuries and illnesses by gender, race, industry, and occupation. In May 2002, sections of the Chartbook were re-packaged in booklets highlighting fatal and nonfatal illnesses and injuries as well as a focus on mining.
Work Related Lung Disease Surveillance Report 2002
DHHS (NIOSH) Publication No. 2003-111 (2002)
The sixth of a series, the Work-Related Lung Disease (WoRLD) Surveillance Report 2002 provides information on various work-related respiratory diseases and associated exposures in the United States. The WoRLD Surveillance Report 2002 describes where these diseases are occurring (by industry and geographic location), who is affected (by race, gender, age, and occupation), how frequently they occur, and temporal trends.
Work Related Lung Disease Surveillance Report 1999
DHHS (NIOSH) Publication No. 2000-105 (1999)
This surveillance report presents summary tables and figures of occupational respiratory disease surveillance data focusing on various occupationally-relevant respiratory diseases, including pneumoconioses, occupational asthma and other airway diseases, and several other respiratory conditions. For many of these diseases, selected data on related exposures are also presented.
Work Related Lung Disease Surveillance Report 1996
DHHS (NIOSH) Publication No. 96-134 (1996)
This 1996 surveillance report provides national and state-specific summaries of occupational respiratory disease surveillance data focusing on pneumoconiosis mortality. Selected occupational respiratory hazard sampling data relevant to pneumoconiosis are also presented.
Work Related Lung Disease Surveillance Report 1994
DHHS (NIOSH) Publication No. 94-120 (1994)
The 1994 Work-Related Lung Disease Surveillance Report (WoRLD) provides a summary of surveillance data for various occupational respiratory diseases from a variety of sources. The majority of the data in this report is for the time period 1968-1990.
Work Related Lung Disease Surveillance Report Supplement 1992
DHHS (NIOSH) Publication No. 91-113s (1992)
Supplement to the first Work Related Lung Disease Surveillance Report (WoRLD) which presents updated data and data which was previously unpresented including sex, race, geographic distribution, industry and occupation; number of discharges with silicosis or asbestosis from the National Hospital Discharge Survey; and reports of occupational asthma and silicosis from the SENSOR program.
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Society and culture


Notable cases

Mesothelioma, though rare, has had a number of notable patients:
  • Bernie Banton, an Australian workers' rights activist, fought a long battle for compensation from James Hardie after he contracted mesothelioma after working for that company. He claimed James Hardie knew of the dangers of asbestos before he began work with the substance making insulation for power stations. Mesothelioma eventually took his life along with his brothers and hundreds of James Hardie workers. James Hardie made an undisclosed settlement with Banton only when his mesothelioma had reached its final stages and he was expected to have no more than 48 hours to live. Australian Prime Minister Kevin Rudd mentioned Banton's extended struggle in his acceptance speech after winning the 2007 Australian federal election.
  • Bob Bellear, Australian anti-racism activist, died in 2005.
  • Frank Bender, American forensic sculptor and co-founder of the Vidocq Society, died in 2011.
  • Michael G. Coney, British science fiction writer, responsible for nearly 100 works, died in 2005.
  • Paul Gleason, American film and television actor perhaps best known for his portrayal of Principal Richard Vernon in the 1985 film The Breakfast Club, died in 2006.
  • Christie Hennessy, the influential Irish singer-songwriter, died of mesothelioma in 2007, and had stridently refused to accept the prognosis in the weeks before his death.[47] Hennessy's mesothelioma has been attributed to his younger years spent working on building sites in London.[48]
  • Richard J. Herrnstein, psychologist and co-author of The Bell Curve, died in 1994.
  • Harold Hopkins, Australian actor who appeared in films such as The Club, Don's Party, Gallipoli, and the TV mini series Sara Dane died from mesothelioma on December 11, 2011 in a Sydney hospital.[49]
  • Hamilton Jordan, Chief of Staff for U.S. President Jimmy Carter and lifelong cancer activist, died in 2008.
  • Lincoln Hall, pioneering Australian mountaineer and a founding director of the Australian Himalayan Foundation. He had previously survived against slim odds stranded near the summit of Mount Everest with altitude sickness in 2006. He passed from mesothelioma in 2012.
  • Peter Leonard, Australian journalist and news presenter from Canberra, died September 23, 2008.
  • Malcolm McLaren, former manager of New York Dolls and Sex Pistols, died on 8 April 2010.
  • John William MacDougall, Scottish Labour MP, died of mesothelioma on August 13, 2008, after fighting the disease for two years.[50]
  • Steve McQueen, American actor, was diagnosed with peritoneal mesothelioma on December 22, 1979. He was not offered surgery or chemotherapy because doctors felt the cancer was too advanced. McQueen subsequently sought alternative treatments at clinics in Mexico. He died of a heart attack on November 7, 1980, in Juárez, Mexico, following cancer surgery. He may have been exposed to asbestos while serving with the U.S. Marines as a young adult—asbestos was then commonly used to insulate ships' piping—or from its use as an insulating material in automobile racing suits (McQueen was an avid racing driver and fan).[51]
  • Bob Miner, one of the founders of Software Development Labs, the forerunner of Oracle Corporation, died of mesothelioma in 1994.
  • Terrence McCann, Olympic gold medalist and longtime Executive Director of Toastmasters, died of mesothelioma on June 7, 2006, at his home in Dana Point, California.
  • Mickie Most, an English record producer, died of mesothelioma in 2003.
  • Merlin Olsen, Pro Football Hall of Famer and television actor, died on March 10, 2010, from mesothelioma that had been diagnosed in 2009.
  • Paul Rudolph, American architect, died in 1997.
  • Billy Vaughn, American bandleader, died in 1991.
  • Bruce Vento, U.S. Congressman, died of mesothelioma in 2000. The Bruce Vento Hopebuilder award is given yearly by his wife at the MARF Symposium to persons or organizations who have done the most to support mesothelioma research and advocacy.
  • Warren Zevon, rock and roll musician and songwriter. After a long period of untreated illness and pain, Zevon was diagnosed with inoperable mesothelioma in the fall of 2002. Refusing treatments that he believed might incapacitate him, Zevon focused his energies on recording his final album The Wind, including the song "Keep Me in Your Heart," which speaks of his failing breath. Zevon died at his home in Los Angeles, California, on September 7, 2003.
  • Admiral Elmo Zumwalt, former head of the U.S. Navy [52]

Notable people who have lived for some time with mesothelioma

Although life expectancy with this disease is typically limited, there are notable survivors. In July 1982, Stephen Jay Gould was diagnosed with peritoneal mesothelioma. After his diagnosis, Gould wrote "The Median Isn't the Message"[53] for Discover magazine, in which he argued that statistics such as median survival are just useful abstractions, not destiny. Gould lived for another 20 years, eventually succumbing to metastatic adenocarcinoma of the lung, not mesothelioma. Paul Kraus, diagnosed in 1997, is considered the longest living mesothelioma survivor in the world. He used a variety of integrative treatment modalities including: Vitamin C megadosage, Ukrain, Traditional Chinese Medicine, and Medical Nutrition Therapy. Kraus, an Australian writer and holocaust survivor wrote a book about his mesothelioma survival. [54]

Legal issues

Main article: Asbestos and the law
The first lawsuits against asbestos manufacturers were in 1929. Since then, many lawsuits have been filed against asbestos manufacturers and employers, for neglecting to implement safety measures after the links between asbestos, asbestosis, and mesothelioma became known (some reports seem to place this as early as 1898). The liability resulting from the sheer number of lawsuits and people affected has reached billions of dollars.[55] The amounts and method of allocating compensation have been the source of many court cases, reaching up to the United States Supreme Court, and government attempts at resolution of existing and future cases. However, to date, the US Congress has not stepped in and there are no federal laws governing asbestos compensation.[56]
History
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. In 1960, an article published by Wagner et al. was seminal in establishing mesothelioma as a disease arising from exposure to asbestos.[57] 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. Prior to the use of advanced microscopy techniques, malignant mesothelioma was often diagnosed as a variant form of lung cancer.[58] In 1962 McNulty reported the first diagnosed case of malignant mesothelioma in an Australian asbestos worker.[59] 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.
In Leeds, England the Armley asbestos disaster involved several court cases against Turner & Newall where local residents who contracted mesothelioma claimed compensation because of the asbestos pollution from the company's factory. One notable case was that of June Hancock, who contracted the disease in 1993 and died in 1997
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Alternative medicine


The medicinal plant Ashwagandha (Withania somnifera) has long been used in Indian Ayurvedic medicine. An extract of this plant, Withaferin A (WA), has been tested in vitro and in vivo as a treatment for malignant pleural mesothelioma (MPM). The authors of these tests have concluded that their data "convincingly demonstrate that WA targets multiple pathways to suppress MPM growth in vitro and in vivo, and underscore its potential as a future anti-MPM therapy".[42] Ashwagandha extracts are commercially manufactured and widely available.

Epidemiology

Although reported incidence rates have increased in the past 20 years, mesothelioma is still a relatively rare cancer. The incidence rate varies from one country to another, from a low rate of less than 1 per 1,000,000 in Tunisia and Morocco, to the highest rate in Britain, Australia and Belgium: 30 per 1,000,000 per year.[43] 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.[44] 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.[45] Between 1973 and 1984, the incidence of pleural mesothelioma among Caucasian males increased 300%. 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.
The incidence of peritoneal mesothelioma is 0.5–3.0 per million per year in men, and 0.2–2.0 per million per year in women.[
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Multimodality therapy


All of the standard approaches to treating solid tumors—radiation, chemotherapy, and surgery—have been investigated in patients with malignant pleural mesothelioma. Although surgery, by itself, is not very effective, surgery combined with adjuvant chemotherapy and radiation (trimodality therapy) has produced significant survival extension (3–14 years) among patients with favorable prognostic factors.[38] However, other large series of examining multimodality treatment have only demonstrated modest improvement in survival (median survival 14.5 months and only 29.6% surviving 2 years).[32] Reducing the bulk of the tumor with cytoreductive surgery is key to extending survival. Two surgeries have been developed: extrapleural pneumonectomy and pleurectomy/decortication. The indications for performing these operations are unique. The choice of operation depends on the size of the patient's tumor. This is an important consideration because tumor volume has been identified as a prognostic factor in mesothelioma.[39] Pleurectomy/decortication spares the underlying lung and is performed in patients with early stage disease when the intention is to remove all gross visible tumor (macroscopic complete resection), not simply palliation.[40] Extrapleural pneumonectomy is a more extensive operation that involves resection of the parietal and visceral pleurae, underlying lung, ipsilateral diaphragm, and ipsilateral pericardium. This operation is indicated for a subset of patients with more advanced tumors, who can tolerate a pneumonectomy.[41]
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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.[36] 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.
This technique is also used in patients with malignant pleural mesothelioma.[37]
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Chemotherapy


Chemotherapy is the only treatment for mesothelioma that has been proven to improve survival in randomised and controlled trials. The landmark study published in 2003 by Vogelzang and colleagues compared cisplatin chemotherapy alone with a combination of cisplatin and pemetrexed (brand name Alimta) chemotherapy in patients who had not received chemotherapy for malignant pleural mesothelioma previously and were not candidates for more aggressive "curative" surgery.[34] This trial was the first to report a survival advantage from chemotherapy in malignant pleural mesothelioma, showing a statistically significant improvement in median survival from 10 months in the patients treated with cisplatin alone to 13.3 months in the group of patients treated with cisplatin in the combination with pemetrexed and who also received supplementation with folate and vitamin B12. Vitamin supplementation was given to most patients in the trial and pemetrexed related side effects were significantly less in patients receiving pemetrexed when they also received daily oral folate 500mcg and intramuscular vitamin B12 1000mcg every 9 weeks compared with patients receiving pemetrexed without vitamin supplementation. The objective response rate increased from 20% in the cisplatin group to 46% in the combination pemetrexed group. Some side effects such as nausea and vomiting, stomatitis, and diarrhoea were more common in the combination pemetrexed group but only affected a minority of patients and overall the combination of pemetrexed and cisplatin was well tolerated when patients received vitamin supplementation; both quality of life and lung function tests improved in the combination pemetrexed group. In February 2004, the United States Food and Drug Administration approved pemetrexed for treatment of malignant pleural mesothelioma. However, there are still unanswered questions about the optimal use of chemotherapy, including when to start treatment, and the optimal number of cycles to give.
Cisplatin in combination with raltitrexed has shown an improvement in survival similar to that reported for pemetrexed in combination with cisplatin, but raltitrexed is no longer commercially available for this indication. For patients unable to tolerate pemetrexed, cisplatin in combination with gemcitabine or vinorelbine is an alternative, or vinorelbine on its own, although a survival benefit has not been shown for these drugs. For patients in whom cisplatin cannot be used, carboplatin can be substituted but non-randomised data have shown lower response rates and high rates of haematological toxicity for carboplatin-based combinations, albeit with similar survival figures to patients receiving cisplatin.[35]
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 Un
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Treatment

Treatment

The prognosis for malignant mesothelioma remains disappointing, although there have been some modest improvements in prognosis from newer chemotherapies and multimodality treatments.[32] Treatment of malignant mesothelioma at earlier stages has a better prognosis, but cures are exceedingly rare. 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. The histological subtype and the patient's age and health status also help predict prognosis. The epithelioid histology responds better to treatment and has a survival advantage over sarcomatoid histology.[33]

Surgery

Surgery, by itself, has proved disappointing. In one large series, the median survival with surgery (including extrapleural pneumonectomy) was only 11.7 months.[32] However, research indicates varied success when used in combination with radiation and chemotherapy (Duke, 2008). (For more information on multimodality therapy with surgery, see below). 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.

Radiation

For patients with localized disease, and who can tolerate a radical surgery, radiation is often given post-operatively as a consolidative treatment. The entire hemi-thorax is treated with radiation therapy, often given simultaneously with chemotherapy. 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

Chemotherapy is the only treatment for mesothelioma that has been proven to improve survival in randomised and controlled trials. The landmark study published in 2003 by Vogelzang and colleagues compared cisplatin chemotherapy alone with a combination of cisplatin and pemetrexed (brand name Alimta) chemotherapy in patients who had not received chemotherapy for malignant pleural mesothelioma previously and were not candidates for more aggressive "curative" surgery.[34] This trial was the first to report a survival advantage from chemotherapy in malignant pleural mesothelioma, showing a statistically significant improvement in median survival from 10 months in the patients treated with cisplatin alone to 13.3 months in the group of patients treated with cisplatin in the combination with pemetrexed and who also
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