LS 120, Lab LS 111Bio 20, Anatomy Andy HuffordMay 6, 2003MesotheliomaAsbestos is the name given to a group of six different fibrousminerals (amosite, chrysotile, crocidolite, and the fibrous varieties oftremolite, actinolite, and anthophyllite) that occur naturally in theenvironment. Asbestos minerals have separable long fibers that are strongand flexible enough to be spun and woven and are heat resistant. Because ofthese characteristics, asbestos has been used for a wide range ofmanufactured goods, mostly in building materials (roofing shingles, ceilingand floor tiles, paper products, and asbestos cement products), frictionproducts (automobile clutch, brake, and transmission parts), heat-resistantfabrics, packaging, gaskets, and coatings. Some vermiculite or talcproducts may contain asbestos.
It is known that breathing asbestos can increase the risk of cancer inpeople. There are two types of cancer caused by exposure to asbestos: lungcancer and mesothelioma.Mesothelioma is a cancer of the thin lining surrounding the lung(pleural membrane) or abdominal cavity (the peritoneum). Cancer fromasbestos does not develop immediately, but shows up after a number ofyears. Studies of workers also suggest that breathing asbestos can increasechances of getting cancer in other parts of the body (stomach, intestines,esophagus, pancreas, and kidneys), but this is less certain.Early identification and treatment of any cancer can increase anindividual’s quality of life and survival.
Malignant mesothelioma attacks the lining of the lungs, heart and/orabdomen.Mesothelioma strikes over 3,000 people each year. The disease isalmost exclusively caused by asbestos exposure. Asbestos is a known toxinthat irresponsible companies continued to market for decades in the face ofscientific evidence proving its danger.Mesothelioma is a highly aggressive cancer that comes in two forms(peritoneal or pleural) and is almost always caused by asbestos exposure.Mesothelioma is the term used to describe a cancerous tumor that involvesthe mesothelial cells of an organ.
Mesothelial cells are cells that form aprotective lining over the lungs, heart and abdominal organs. The mostcommon type of mesothelioma is pleural mesothelioma. The pleura are a thinmembrane found between the lungs and the chest cavity. It provides alubricated surface so that the lungs do not rub and chafe against the chestwalls.Virtually all cases of mesothelioma are related to inhaling ofasbestos fibers. There are about 3,000 cases per year (mostly men over theage of 40) and there will be about 300,000 cases before 2030.Mesothelioma usually spreads rapidly through the mesothelial cells tothe heart and abdominal organs. The life span is typically 24 months afterdiagnosis, but it depends on what stage the cancer is detected, the healthof the patient and other factors.
Although asbestos exposure causesmesothelioma, it has a latency period after exposure that could last 15 to50 years. This means that someone who worked in a factory with asbestos 40years ago could be developing mesothelioma now. Anyone who knows they wereexposed to loose asbestos fibers should be tested regularly formesothelioma.The onset of mesothelioma is usually very slow. The first symptom is aconstant pain in the chest. This pain is later accompanies by difficultybreathing due to an accumulation of fluid in the chest. Other symptomsinclude coughing, fever and weight loss. Mesothelioma can be by your doctorwith a diagnosed with a chest CT-scan.
Mesothelioma advances in 4 stages:Stage I – the tumor is limited to the area of the lining of the lungand usually limited to only one side of the chest. Stage II – the tumorextends to other organs within the chest cavity, such as the heart or lymphnodes in the chest. Stage III – the tumor expands to the other side of thechest or it spreads into the abdominal organs. The lymph nodes outside thechest are affected. Stage IV -the cancer spreads to different parts of thebody far outside the chest area (liver, brain, bone, etc.
)Mesothelioma is an extremely deadly disease. The average survivaltime is about one year from date of diagnosis. About 20% of patients whofind their cancer early and treat it aggressively will reach the five-yearmark.Mesothelioma is nearly always related to Asbestos exposure. Asbestos is anextremely dangerous material and low exposure levels can triggerMesothelioma. This means that even family members of asbestos workers areat risk because of the asbestos fibers brought into the home on theirclothing.Scientists have known about asbestos’s carcinogenic (cancer-causing)properties since the 1930’s, but asbestos was a cheap insulator andfireproofing material.
Corporations continued to put workers and theirfamilies at risk for decades after its lethality was discovered.If you have Mesothelioma, you are invariably a victim of asbestos, amaterial whose danger was known as early as the 1930s. Many asbestosmanufacturers and corporate users of asbestos materials ignored thescientific data showing asbestos’ lethality. In the end, workers who had towork with the material were the ones who sufferedOriginally, asbestos was viewed as a miracle material. It isinexpensive and an excellent insulator and fireproof material. However,around the turn of the century, researchers noticed a large numbers ofdeaths and lung problems in asbestos mining towns.Treatment OptionsAfter diagnosis, your doctor or oncologist (cancer specialist) willprovide you with information on the treatment options that are available toyou. They are, Surgery, Radiotherapy, Chemotherapy, and AlternativeTherapies.
There are two types of surgeries, those that actually remove thecancer itself and those that help alleviate pain and suffering (symptoms).If the cancer has not spread to too many organs, surgery can be used toremove part of the lining of the chest or abdomen. The purpose of thissurgery is to simply remove the cancer cells from the body by removing thetissues with large numbers of cancer cells. More serious operations canremove large parts of the lung or the diaphragm.
The more seriousoperation requires the patient to be in excellent health.If the cancer has spread to several organs, it is impossible to removeall of the tissue infected with cancer. In this case, surgery can only beused to relieve symptoms. One operation is a thoracentesis, where fluid inthe chest is removed by placing a needle into the chest cavity, may help toimprove comfort and breathing. This procedure does nothing to cure thecancer, only to relieve the symptoms.Radiation therapy is sometimes used as the main treatment ofMesothelioma in some patients, especially those whose general health is toopoor to undergo surgery. Radiation may also be used to supplement surgery.
Chemotherapy is the use of drugs for treating cancer. The drugs can beswallowed in pill form or a needle into a vein or muscle can inject them.The drug enters the bloodstream and circulates throughout the body to reachand destroy the cancer cells.
While surgery and radiation (above) can target specific areas,chemotherapy targets the entire body and can kill normal cells. This meansthat chemotherapy can have severe side effects. Chemotherapy can also beinjected directly into specific locations, such as the chest. Chemotherapycan be used in combination with a variety of drugs to increase the totaleffect.
Chemotherapy is often used in combination with other treatments,such as surgery.Many alternative therapies are available for Mesothelioma. Thesetherapies generally are not as well tested as the above therapies, but atany time a new discovery or study could make one of these therapies thestandard in Mesothelioma treatment.Gene TherapyThese therapies change the genetic structure of organisms to defeatMesothelioma. Gene therapies are still in development and few have shownpractical benefit to date.Photodynamic TherapyThis therapy involves using a drug to make cancer cells sensitive to aparticular light wavelength.
The cells would then be exposed to that lightwavelength to kill the Mesothelioma cells. This form of treatment is stillcontroversial and experimental, but improvements may occur.New treatments are being researched all the time. Organizations suchas the National Cancer Institute and the American Cancer Society areparticipating in clinical trials to test how well new drugs and therapiesbattle Mesothelioma.