Sunday, November 1, 2009
Mesothelioma
Mesothelioma is a form of cancer that is almost always caused by 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, 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. It has also been suggested that washing the clothes of a family member who worked with asbestos can put a person at risk for developing mesothelioma.Unlike lung cancer, there is no association between mesothelioma and smoking, but smoking greatly increases risk of other asbestos-induced cancer.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.
Contents
1 Signs and symptoms
2 Diagnosis
3 Screening
4 Staging
5 Pathophysiology
6 Epidemiology
6.1 Incidence
6.2 Risk factors
6.3 Exposure
6.3.1 Environmental exposures
6.3.2 Occupational
6.3.3 Paraoccupational secondary exposure
6.3.4 Asbestos in buildings
7 Treatment
7.1 Surgery
7.2 Radiation
7.3 Chemotherapy
7.4 Immunotherapy
7.5 Heated Intraoperative Intraperitoneal Chemotherapy
8 Notable people who died from mesothelioma
9 Notable people who have lived for some time with mesothelioma
10 Legal issues
11 History
12 References
13 Footnotes
14 See also
15 External links
Signs and symptoms
Symptoms of mesothelioma may not appear until 20 to 50 years after exposure to asbestos. Shortness of breath, cough, and pain in the chest due to an accumulation of fluid in the pleural space are often symptoms of pleural mesothelioma.
Symptoms of peritoneal mesothelioma include weight loss and cachexia, abdominal swelling and pain due to ascites (a buildup of fluid in the abdominal cavity). Other symptoms of peritoneal mesothelioma may include bowel obstruction, blood clotting abnormalities, anemia, and fever. If the cancer has spread beyond the mesothelium to other parts of the body, symptoms may include pain, trouble swallowing, or swelling of the neck or face.
These symptoms may be caused by mesothelioma or by other, less serious conditions.
Mesothelioma that affects the pleura can cause these signs and symptoms:
Chest wall pain
Pleural effusion, or fluid surrounding the lung
Shortness of breath
Fatigue or anemia
Wheezing, hoarseness, or cough
Blood in the sputum (fluid) coughed up (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.
Diagnosis
CT scan of a patient with mesothelioma, coronal section (the section follows the plane that divides the body in a front and a back half). The mesothelioma is indicated by yellow arrows, the central pleural effusion (fluid collection) is marked with a yellow star. Red numbers: (1) right lung, (2) spine, (3) left lung, (4) ribs, (5) descending part of the aorta, (6) spleen, (7) left kidney, (8) right kidney, (9) liver.
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.
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Disease
Tuesday, October 6, 2009
Pleural Mesothelioma Treatment: Choosing the Mesothelioma Treatment That Is Right for You
Facing a diagnosis of pleural mesothelioma is not an easy task. You can fight the feeling of hopelessness by learning as much as you can about mesothelioma treatment as well as the details of your own medical situation. This will help you work with your doctors to make decisions that are best for you and your family. We recommend consulting both your family physician and a pulmonary (lung) specialist who has dealt with pleural mesothelioma patients and is familiar with the problems of asbestos exposure.
Asking Your Doctor About Pleural Mesothelioma
You may want to write down questions to ask your doctor in preparation for your office visit. This can help you focus your thoughts and make sure that you understand basic medical information. Also consider taking a relative or friend with you for support. The American Cancer Society provides this suggested list of questions:
» What is the stage of my mesothelioma (i.e. how advanced is it)?
» Has the pleural mesothelioma spread beyond its original site?
» What is my prognosis?
» What mesothelioma treatment options do I have? Which of these options do you recommend, and why?
» What risks or side effects are there to the pleural mesothelioma treatments you suggest?
» What are the chances that my cancer will recur with these treatment plans?
» What should I do to be ready for mesothelioma treatment?
You may also have other questions and concerns about day–to–day living, mesothelioma treatment recovery times, or about clinical trials, which are research studies that test the safety and effectiveness of new pleural mesothelioma therapies on patients. You should feel free to add new items to your list. The more candid the conversation you have with your doctor, the better you will be able to cope with your diagnosis.
Pleural Mesothelioma Treatment Options
The treatment method that you choose will depend on how advanced your disease is, your general physical health, and personal preferences. At this point in time, pleural mesothelioma cannot be cured, although some therapies, such as the chemotherapy drug, ALIMTA® , may decrease pain and promote survival or a better quality of life.
Some doctors use a combination of mesothelioma therapies such as surgery plus chemotherapy, or surgery, chemotherapy, and radiation therapy. This is called “multimodality therapy.” Another common pleural mesothelioma treatment technique is to base the procedures on whether the cancer has spread, and if so, how far (see Mesothelioma Diagnosis: Staging). The current available treatment options include surgery, chemotherapy, and radiation. Photodynamic therapy and immunotherapy are in the experimental stages of development.
The field of pleural mesothelioma research is in constant flux. We will keep you up–to–date about new drugs and other medical treatments in our medical news section. You will want to carefully discuss new mesothelioma treatment options with your doctor, as well as the more standard ones.
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Mesothelioma treatment
Friday, October 2, 2009
Types of mesothelioma treatment
Surgery
In some cases, surgery may be recommended to alleviate symptoms or slow the progression of mesothelioma. Surgery may be performed in tandem with other treatments such as chemotherapy and radiation, also known as “multi-modal therapy.”
As scientists develop tests to diagnose mesothelioma at an earlier stage, surgery could play a role in curing the disease in the future. Doctors specializing in mesothelioma are working toward the goal of using surgery to remove the cancer and the necessary surrounding tissue in an effort to stabilize the disease.
Whether a surgery is recommended for a particular patient will depend on factors unique to each person, including the type and location of the cancer, the “stage” of the cancer and the patient’s overall health.
Even among the subgroup of patients for whom surgery is an appropriate option, there are a variety of surgical procedures that may be considered—some to control the buildup of fluid that can cause such discomfort and others to remove the tumor mass and slow progression of the disease.
For a patient with pleural mesothelioma, which affects the membrane surrounding the lungs, a surgeon may be called up to perform a thoracentesis, pleurodesis or pleurectomy/decortication to relieve or control discomfort and plural effusion, the buildup of fluid around the lungs that can cause pain and shortness of breath. Other surgeries, such as a pneumonectomy or an extrapleural pneumonectomy, remove more extensive tissue in an attempt to slow tumor progression.
For a patient dealing with peritoneal mesothelioma, which attacks the membrane lining the abdomen, the surgeon may relieve a peritoneal effusion, the buildup of fluid in the abdomen, through a paracentesis. The lining of the abdomen, called the peritoneum, may be removed by a peritonectomy. In a cytoreductive surgery, surgeon will open the abdomen and remove every visible sign of cancer.
Finally, for patients dealing with the most rare form of mesothelioma that involves the membrane surrounding the heart (pericardial mesothelioma), a surgeon might perform a pericardiocentesis to drain the buildup of fluid around the heart, or the more aggressive extrapleural pneumonectomy may be used in some cases to remove the tumor and surrounding tissues.
Types of surgery for mesothelioma treatment:
Thoracentesis
This procedure involves the draining of fluid that may build up (called a “pleural effusion”) in the chest between the lung and the pleura. A tube is placed in the chest in order to drain out the fluid. Thoracentesis is a palliative treatment, meaning that its purpose is to help relieve discomfort.
Pleurodesis
Pleurodesis is a surgical procedure to help control pleural effusion, which is the buildup of fluid between the lungs and the lung lining. Pleurodesis closes the space between the lung and the lung lining, reducing the chance for fluid to accumulate.
There are two approaches to performing a pleurodesis. In the first, a tube that is inserted into the chest drains the excess fluid. After this fluid is drained, a schlerosing agent (a substance that causes tissue to scar or harden), such as sterile talc powder, is injected through the chest tube and into the pleural space. The schlerosing agent is allowed to distribute itself through the pleural space, with the patient being asked to move about in order to facilitate the distribution. Once the agent is distributed, suction is applied to the tube in the chest. Similar to collapsing a plastic bag, the suction brings the two pleural surfaces together, allowing them to “scar” together.
The second method of pleurodesis uses thoracoscopy, whereby a small incision, or a series of small incisions, are made in the skin. A thoracoscope is passed through the incision in order to get a better look at the pleura. The schlerosing agent is then applied to the area.
Pleurectomy/decortication
Pleurectomy/decortication involves removing the pleura, where most of the tumor is located. This procedure may help control pleural effusions (fluid buildup) and help to decrease the pain caused by the tumor. It is a palliative treatment, meaning that its goal is to help to lessen the discomfort caused by mesothelioma.
Pneumonectomy
A pneumonectomy is the removal of all or part of the lung. Your surgeon will make an incision in the side of the chest. When the lung is revealed, the surgeon visually assesses the tumor and decides how much tissue should be removed.
Extrapleural Pneumonectomy
This extensive surgery usually involves the removal of the pleura, pericardium, diaphragm and the whole lung on the side of the cancerous tumor. Your surgeon may decide to remove some of the surrounding tissues as well.
Paracentesis
Peritoneal mesothelioma can cause fluid to build up in the abdomen in a process called peritoneal effusion. This excess fluid is drained through a needle and tube inserted into the abdomen. Paracentesis (sometimes called an “ascitic tap”) can help take the pressure off the internal organs, and also helps reduce the risk of infection that may be caused by the fluid buildup. This is a “palliative” procedure, meaning that the goal of paracentesis is to help to relieve the discomfort associated with peritoneal mesothelioma.
Peritonectomy
A “peritonectomy” involves removing the peritoneum, the lining of the abdomen where the mesothelioma first develops. This form of surgery is most often used when the cancer is detected in the very early stages of the disease. Your surgeon might recommend that a peritonectomy be performed in tandem with “intraperitoneal hypothermic perfusion,” a form of heated chemotherapy where the chemotherapy drugs are administered directly into the abdomen during and/or after surgery.
Cytoreductive surgery
During cytoreductive or “debulking” surgery, the surgeon opens the abdominal cavity (a procedure known as a “laparotomy”) to look for all signs of cancer and attempt to remove as much of the tumor as possible. This surgery can be quite long in duration because of the amount of detail the surgeon must use to search for and remove signs of cancer in the abdominal area. Your surgeon might recommend that this surgery be performed in tandem with “intraperitoneal hypothermic perfusion,” a form of heated chemotherapy administered into the abdominal cavity.
Pericardiocentesis
This is the process for drawing fluid out of the affected area to help to relieve the discomfort associated with pericardial mesothelioma. For this procedure, a needle is inserted into the pericardium (the sac around the heart) to drain the fluid and relieve circulatory problems. The draining of this fluid can be associated with complications, however.
Radiation
Radiation therapy is an intense X-ray treatment to damage or kill cancer cells. Although not a cure for mesothelioma, radiation therapy nonetheless may be used at different stages of the disease to slow its growth. Radiation is often the main treatment for patients in weak health who are not candidates for surgery. When radiotherapy is used following surgical removal of the tumor, it is called adjuvant therapy. This type of therapy—surgery followed by radiation—has been demonstrated to reduce the local recurrence of the tumor and to improve the survival rate of patients with early-stage disease. Adjuvant therapy is also an essential part of the treatment of patients who undergo an extrapleural pneumonectomy.
Radiation therapy is important not just to control the growth of the tumor. Radiotherapy is also used to relieve the symptoms of mesothelioma by reducing pain, improving breathing, and easing the other physical problems caused by the cancer.
The kind of radiation treatment used for each patient will depend on several factors, including the size of the tumor and how close it is to vital organs, the stage of the disease, and whether other treatment options may also be used.
There are two primary types of radiation therapy used for mesothelioma patients: traditional external beam radiotherapy and brachytherapy. In addition, mesothelioma doctors are now employing a new form of radiotherapy, intensity-modulated radiation therapy (IMRT).
Adjuvant therapy
Adjuvant therapy is additional treatment to reduce the risk or cancer recurrence or increase the time before cancer recurs. Through the use of chemotherapy, radiation or other adjuvant therapies after a primary treatment like surgery, cancer specialists attempt to kill cancer cells that were left behind in the body but are too small to be seen. Adjuvant therapies, like all cancer treatments, also pose side effects that must be weighed in deciding whether to proceed with a possible treatment.
External Beam Radiation
External beam radiation therapy (EBRT) is routed to the site of the tumor with the use of linear accelerators. These machines generate high-energy external radiation beams that reach through the tissues into the areas where the tumor is found. To deliver the radiation precisely, doctors use computed tomography (CT) scans and PET scans to focus on the areas where the tumor is likely to reappear. Careful radiation planning allows the radiologist to direct a higher dose of radiation at the tumor tissue and to minimize the amount of normal tissue that will be exposed to this high dose of radiation.
Brachytherapy
Brachytherapy uses radioactive substances rather than radiation beams to deliver radiation treatments. The word “brachy” comes from the Greek, and means “short range.” This type of radiation therapy is different from external beam radiation, which is administered over a long range.
Because the radioactive substances used in brachytherapy will only work in the short range, they must be placed in or very near the target area of the body. This means that brachytherapy can be used for mesothelioma patients only by surgically implanting the radioactive substances. This therapy is generally performed during the same operation in which the tumor is removed, and is sometimes referred to as “Intraoperative Radiation Therapy” (IORT). For brachytherapy, the thoracic surgeon and radiation oncologist measure the areas of the chest cavity from which the mesothelioma and surrounding tissue cannot be fully removed. Then, a customized implant is created by weaving radioactive seeds into an absorbable mesh, known as a radioactive iodine seed implant. This flexible mesh is stitched into the body during surgery. The radiation from the implant is released over a three-month period, with a small amount of radioactivity still present for about a year. It is critical during this therapy not to increase a patient’s time in surgery too long, or complications may develop as a result of this delay. Doctors are still evaluating the overall benefits and risks of this procedure.
Intensity-modulated radiation therapy (IMRT)
Intensity-modulated radiation therapy (IMRT) is a new breakthrough in radiation oncology. The therapy allows for treatment of areas of the body that previously could not be treated with conventional radiation. IMRT for mesothelioma is delivered by a team of physicians, including a radiation oncologist, physicist and radiation therapist. The preliminary results for this new therapy suggest that the rate of local recurrence is significantly reduced for mesothelioma patients undergoing this treatment.
Chemotherapy
Chemotherapy uses certain chemical agents or drugs that are specifically destructive to malignant tissues and cells. Doctors may recommend single agent chemotherapy or a combination chemotherapy treatment. The single agent chemotherapy treatment involves the use of just one type of chemical or drug. The combination chemotherapy method involves the use of more than one chemical or drug. While it is not a cure for mesothelioma, chemotherapy treatment may help to prevent the spread of the disease or slow its growth. Chemotherapy may also shrink tumors before surgery is performed (called neoadjuvant therapy), destroy tumor cells still remaining after surgery (called adjuvant therapy), and relieve symptoms, such as pain (called palliative therapy).
Generally, chemotherapy drugs are delivered by injection into a vein. Depending on the type and location of the cancer and the drug used, however, the chemotherapy drugs may be delivered by mouth, into the muscle or skin or by placing the drugs directly into a body cavity (called intracavitary chemotherapy).
Chemotherapy drugs usually cause fatigue or exhaustion. Patients also may experience nausea, vomiting and hair loss. Specific side effects will vary, based on the drug, its dosage, and the length of treatment. Other chemotherapy-related drugs and therapies may minimize the side effects or will be prescribed for use following chemotherapy
Clinical Trials
Clinical trials are conducted on all new therapies and drugs before the FDA approves them for use by the general public. Many medications and treatments that are now the standard of care for certain diseases have gone through a lengthy period of testing with clinical trials. These carefully controlled studies are always in need of patients willing to try the experimental treatments. Many patients with aggressive illnesses or those with no known cure willingly participate in a clinical trial as a last hope. Patients should ask their doctors about currently available clinical trials to determine whether they might qualify to participate in a particular study. Those choosing to take part in a clinical trial should carefully weigh the risks and benefits before agreeing to participate.
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A clinical trial has three stages. Phase I trials involve just a limited number of people. They generally focus on a drug’s correct dosage and relative safety. Phase II trials enlist more people and concentrate on whether the new drug is effective in fighting a particular illness. Phase III is the final phase of a clinical trial in which the new medication is compared against any existing treatment to determine whether the new treatment is more effective than the old.
Enrolling in a Clinical Trial
Many factors should be considered when deciding whether to take part in a clinical trial. Such trials usually are held in large metropolitan hospitals. Patients need to know how often they must see the physicians coordinating the trials and how much time each visit will take, since travel expenses can be quite costly.
Often, it is difficult to qualify for a clinical trial. To gain the most information possible from a clinical trial, the trial coordinator will place strict controls on the group of qualified patients. In some clinical trials, a patient must have already had unsuccessful traditional treatment. Other clinical trials only enroll patients who have not yet undergone any treatment for mesothelioma.
A patient’s general health will also affect qualification. Mesothelioma patients with other medical conditions and those taking drugs for other illnesses will likely be excluded from clinical trials. By studying only patients who are being treated for one disease with one therapy, researchers are given a more accurate assessment of the effectiveness of the experimental mesothelioma treatment.
Patients must also consider that participation in a clinical trial requires the relinquishment of control over medical treatment. For example, some clinical trials are referred to as randomized studies. In such trials, one group of patients receives the traditional treatment while another group is given the new experimental treatment. But the patients do not select which treatment they receive, nor are they told which treatment is being administered. A patient’s participation in a clinical trial is not a guarantee that the patient will receive anything other than the traditional therapy.
Still, there are enormous benefits associated with clinical trials. Without them, it would be very difficult to test the effectiveness of new medications. And clinical trials offer participants thorough and high quality health care. Meticulous records are kept and extensive testing is performed on each patient to gauge a new treatment’s effectiveness and safety. Clinical trials for mesothelioma are a critical part of finding a cure.
Ongoing Mesothelioma Clinical Trials
A variety of resources on the Internet discuss ongoing clinical trials for mesothelioma and include the qualifications for each trial. Patients interested in taking part in a clinical trial should consult their doctor. Physicians specializing in mesothelioma are kept abreast of all upcoming and current clinical trials, and are able to determine whether a patient qualifies for a particular trial. Large regional cancer centers also have access to current information on clinical trials that are coordinated through the regional hospitals.
Some of clinical trials are reportedly still recruiting participants; some are actively testing new treatments but are not currently seeking participants. Others have already been completed and may provide helpful information to physicians following the development of new mesothelioma treatments. More information about these trials and other clinical trials can be located on the Internet at the National Institute of Health’s Database of Clinical Trials, from which we have collected the information provided on this site. Again, patients should consult their doctors to determine whether a particular trial is available to them.
Innovative Mesothelioma Therapies
Traditional cancer treatment regimens such as radiation and chemotherapy are widely used for mesothelioma patients, but they do not offer a cure for the disease. Increasingly, patients have turned to unconventional forms of therapy in the hope that the answer lies with gene therapy, immunotherapy or photodynamic therapy. All of these treatment options should be discussed with the patient’s physician prior to setting out on a course of alternative treatment.
Gene Therapy
Gene therapy is a method for correcting defective genes that cause disease development. The therapy can work in several ways. Scientists can correct defective genes by removing, inserting, replacing, or altering genes in order to treat or prevent a disease.
To treat a disease such as mesothelioma, a carrier called a ‘vector’ would be used to deliver the therapeutic gene. Generally, viruses are used because they already have the capacity to invade a cell. Also, viruses are very good at targeting specific cells. In gene therapy, viral vectors are changed so they do not create a new virus in the cell, but just drop off a new gene.
Many scientists are searching for ‘suicide genes’ that would attack cancer cells, while leaving normal cells untouched. Gene therapy is a fairly new treatment approach, still very much in the experimental stages, and cannot be administered without the patient’s participation in a clinical trial.
Immunotherapy
Immunotherapy is also known as biological therapy, biotherapy, or biological response modifier (BRM) therapy. It is a treatment designed to stimulate the body’s own natural immune defenses to stop the spread of cancer. Scientists have determined that the immune system can recognize and eliminate cancer cells under some circumstances. The problem with mesothelioma is that the body does not recognize the cancer cells as abnormal.
Immunotherapy uses BRMs to boost the body’s natural ability to fight disease. Interferons, interleukins, tumor necrosis factors, monoclonal antibodies and cancer vaccines are all BRMs. Some occur naturally in the body, and others are generated synthetically in the lab. BRMs seem to change the body’s relationship with mesothelioma cells, so the body recognizes them as abnormal. As a result, the body’s ‘immune response’ kicks in to attack the mesothelioma cells and prevent the cancer from growing. Immunotherapy also seeks to block the process by which mesothelioma alters a normal cell into a cancer cell. Scientists hope that BRMs can stop the migration of mesothelioma to other parts of the body, and prevent its further growth.
Preliminary studies have demonstrated considerable shrinkage of tumors at very early stages of mesothelioma. But more research is required to determine whether immunotherapy will be effective as a mesothelioma treatment. In Phase I and Phase II clinical trials of a combined immunotherapeutic and chemotherapeutic approach for mesothelioma patients, the results failed to show any meaningful effect on survival or relapse rate.
Photodynamic Therapy
Photodynamic therapy (PDT) uses a drug that is activated by light and applies laser light to it. The two work together to target and destroy cancer cells while keeping damage to surrounding healthy tissue at a minimum. The therapy begins with the patient’s injection with a non-toxic photosensitizer drug. The drug invades all cells of the body, but in about two days, normal cells excrete the drug. Then the patient is exposed to laser light, which will activate the drug remaining in the cancer cells and destroy them. Timing is critical, because the tumor cells must be exposed to the laser light after the drug is excreted by the normal cells, but before the drug is expelled by the mesothelioma cells.
It is unclear what role photodynamic therapy may play in the treatment of mesothelioma. Since the laser light cannot be absorbed at any great depth in the body, treatment via PDT can only be used on superficial areas of the body. Still, the treatment may be ideal for the treatment of mesothelioma after surgical removal of the tumor. Some doctors have applied PDT intraoperatively after surgery, but the number of patients treated in clinical trials is small, making it difficult to draw definitive conclusions. Most reports concerning PDT are Phase I and II studies and the only phase III study was conducted with an earlier generation photosensitizer. That study reported no advantage in using PDT in combination with surgery and immunochemotherapy. At present, all that is known is that PDT can be performed safely with newer generation photosensitizers and that results are encouraging for mesothelioma patients with stages I and II disease.
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The medical team:Physians who treat mesothelioma
After a patient is diagnosed with mesothelioma, he or she will generally be referred by the general practitioner or family doctor to a doctor who specializes in cancer treatment—an oncologist. The oncologist is the doctor who determines the stage of the disease and charts a course of treatment.
The oncologist may work with several other types of experts in treating mesothelioma. If radiation is needed, the patient will see a radiation oncologist or therapeutic radiologist. These are physicians who specialize in conducting radiation (high levels of x-rays) of cancerous tumors in an effort to kill the cancer cells.
Many patients will be referred to a thoracic surgeon, a doctor who specializes in surgery of the chest area. A pulmonologist may also be an important part of the medical team who treat a mesothelioma patient. Some patients who do require surgery will see a pulmonary therapist afterward. Pulmonary therapists work with all types of patients (not just surgery patients) to help recover lost lung function. Some patients may be directed to a pulmonologist, a specialist of the lungs.
In addition, it is quite common for mesothelioma patients to be referred to a psychologist. Mesothelioma is a difficult, painful, aggressive disease that leaves many patients with conflicting emotions about treatment and their future. But patients need to maintain a positive attitude during their treatment in order to receive the maximum benefit from it. A psychologist can help immeasurably during this process.
A mesothelioma patient needs a team of specialists to work together during the treatment process. But the patient is also part of the process. Patients should ensure that they find a mesothelioma doctor with whom they feel comfortable. They should insist on understanding what is happening at each phase in the treatment and not be shy about asking questions. Finally, patients should not hesitate to speak up should something seem strange or inappropriate. And of course, patients are always entitled to seeking a second opinion.
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Data supports furthur investigation of mesothelioma virotherapy
Oncolytics Biotech presented data that indicates malignant mesothelioma cells are sensitive to certain viruses. Their presentation titled “Combination Immunotherapy and Oncolytics Virotherapy for the Treatment of Malignant Mesothelioma” discussed in vitro data showing mesothelioma cells could be suitable targets for reoviruses which could then attack and compromise them.
The company currently has 7 ongoing phase I and phase II trials though none are currently for mesothelioma patients. Reoviruses, which the company is investigating, are generally gastrointestinal infections with the most common form being the rotavirus.
The goal of virotherapy is to isolate and reprogram viruses to only attack cancerous cells. It is still a relatively undeveloped field within cancer research but progress is being made
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How to recognize and treat mesothelioma?
Though mesothelioma is a fairly rare cancer, several thousands of Americans are diagnosed with mesothelioma cancer each year - a rate that is expected to grow before it subsides. Mesothelioma is a cancer that develops in the mesothelium almost always as a result of exposure to asbestos.
What is the mesothelium? The mesothelium is a layer of protective tissue that surrounds a majority of the organs in the human body. When we talk about the pleurae that surround our lungs, for example, we are talking about mesothelium. The mesothelium is composed of two layers of tissue - one that tightly hugs the organ, and the other that encases (between it and the inner layer) a lubricant, which is created by the mesothelium. You may have wondered why you feel little discomfort with all of those sensitive organs rubbing and bumping in your body. Thank your mesothelium.
Who is at risk? Statistically, mesothelioma has appeared more in older men than women, but that has nothing to do with any preference for older men. Men traditionally have been exposed to more asbestos through occupation. That occupational history, coupled with the fact that the disease doesn't necessarily present itself symptomatically until as many as fifty years from exposure, accounts for the predominance of older, male mesothelioma patients.
Those most at risk are people who have been directly exposed to asbestos. However, studies suggest that loved ones might also be at risk of developing mesothelioma as a result of the trace amounts of asbestos that linger on the body and clothing of someone directly exposed to asbestos. Mesothelioma can appear in those with no knowledge of any asbestos exposure.
Exposure to asbestos can bring about the ingestion or inhalation of particulate asbestos matter. Whether swallowed or inhaled, asbestos enters the mesothelium, where the resultant cell damage leads to mesothelioma. Even barring the development of mesothelioma, asbestos can lead to lung and other forms of cancer, as well as asbestosis, wherein scar tissue gradually replaces the delicate lung tissue.
Symptoms of mesothelioma. The symptoms of this form of cancer often bear an unfortunate resemblance to symptoms of more common ailments and do not surface until advanced stages of the cancer. Due to the difficulty of accurate and timely diagnosis, the average life expectancy after diagnosis is little more than a year. Symptoms also will vary depending upon the location of the afflicted mesothelium in the body. The majority of mesothelioma cases begin in the chest (pleural mesothelioma) and abdomen (peritoneal mesothelioma).
Symptoms of pleural mesothelioma include shortness of breath, a cough, and chest pain caused by pleural effusion (accumulation of fluid in the pleura).
Peritoneal mesothelioma presents itself differently. Symptoms include pain in the abdomen, loss of weight, and abdominal swelling (again due to accumulation of fluid, this time in the abdomen).
Mesothelioma diagnosis. Your doctor will arrive at a diagnosis by studying your history (medical, occupational and residential), performing a physical examination and conducting diagnostic work like a CT scan or MRI. In order to prove the presence of mesothelioma, a biopsy will be performed to remove a small sample of the endangered mesothelium for further diagnostic procedures.
Treatment of mesothelioma. As stated earlier, prognosis has traditionally been grim, due to the fact that the cancer often goes undetected until it has reached a critical stage in a generally older patient population. Course of treatment depends on the location of the mesothelioma, the age and health of the patient, and whether or not the cancer has spread to other parts of the body. Traditional treatment options include the following.
Surgical removal of cancerous tissue (often including the removal of a lung or removal of mesothelial tissue and neighboring tissue).
Chemotherapy - intravenous or intracavitary (wherein the chemotherapy is administered directly at the scene of the mesothelioma).
Radiation therapy - external (radiation emitted by a machine) or internal (radiation emitted by a device inserted into your body at the scene of the mesothelioma).
The medical community is engaged in a continual effort to develop more successful treatment plans for patients who suffer from mesothelioma. Resulting clinical trials offer mesothelioma patients an opportunity to participate in promising new treatment methods. It must be noted, however, that the safety and efficacy of these clinical trial treatments are uncertain.
As outlook and treatment are affected by the stage at which mesothelioma is diagnosed, be vigilant in seeking medical attention early and throughout your life. If you have a history of asbestos exposure, see your doctor and convey your experiences. If you are diagnosed with mesothelioma, maintain a positive outlook, buoyed by the support of the medical community and of other mesothelioma patients, and by the knowledge that others have survived mesothelioma.
What is the mesothelium? The mesothelium is a layer of protective tissue that surrounds a majority of the organs in the human body. When we talk about the pleurae that surround our lungs, for example, we are talking about mesothelium. The mesothelium is composed of two layers of tissue - one that tightly hugs the organ, and the other that encases (between it and the inner layer) a lubricant, which is created by the mesothelium. You may have wondered why you feel little discomfort with all of those sensitive organs rubbing and bumping in your body. Thank your mesothelium.
Who is at risk? Statistically, mesothelioma has appeared more in older men than women, but that has nothing to do with any preference for older men. Men traditionally have been exposed to more asbestos through occupation. That occupational history, coupled with the fact that the disease doesn't necessarily present itself symptomatically until as many as fifty years from exposure, accounts for the predominance of older, male mesothelioma patients.
Those most at risk are people who have been directly exposed to asbestos. However, studies suggest that loved ones might also be at risk of developing mesothelioma as a result of the trace amounts of asbestos that linger on the body and clothing of someone directly exposed to asbestos. Mesothelioma can appear in those with no knowledge of any asbestos exposure.
Exposure to asbestos can bring about the ingestion or inhalation of particulate asbestos matter. Whether swallowed or inhaled, asbestos enters the mesothelium, where the resultant cell damage leads to mesothelioma. Even barring the development of mesothelioma, asbestos can lead to lung and other forms of cancer, as well as asbestosis, wherein scar tissue gradually replaces the delicate lung tissue.
Symptoms of mesothelioma. The symptoms of this form of cancer often bear an unfortunate resemblance to symptoms of more common ailments and do not surface until advanced stages of the cancer. Due to the difficulty of accurate and timely diagnosis, the average life expectancy after diagnosis is little more than a year. Symptoms also will vary depending upon the location of the afflicted mesothelium in the body. The majority of mesothelioma cases begin in the chest (pleural mesothelioma) and abdomen (peritoneal mesothelioma).
Symptoms of pleural mesothelioma include shortness of breath, a cough, and chest pain caused by pleural effusion (accumulation of fluid in the pleura).
Peritoneal mesothelioma presents itself differently. Symptoms include pain in the abdomen, loss of weight, and abdominal swelling (again due to accumulation of fluid, this time in the abdomen).
Mesothelioma diagnosis. Your doctor will arrive at a diagnosis by studying your history (medical, occupational and residential), performing a physical examination and conducting diagnostic work like a CT scan or MRI. In order to prove the presence of mesothelioma, a biopsy will be performed to remove a small sample of the endangered mesothelium for further diagnostic procedures.
Treatment of mesothelioma. As stated earlier, prognosis has traditionally been grim, due to the fact that the cancer often goes undetected until it has reached a critical stage in a generally older patient population. Course of treatment depends on the location of the mesothelioma, the age and health of the patient, and whether or not the cancer has spread to other parts of the body. Traditional treatment options include the following.
Surgical removal of cancerous tissue (often including the removal of a lung or removal of mesothelial tissue and neighboring tissue).
Chemotherapy - intravenous or intracavitary (wherein the chemotherapy is administered directly at the scene of the mesothelioma).
Radiation therapy - external (radiation emitted by a machine) or internal (radiation emitted by a device inserted into your body at the scene of the mesothelioma).
The medical community is engaged in a continual effort to develop more successful treatment plans for patients who suffer from mesothelioma. Resulting clinical trials offer mesothelioma patients an opportunity to participate in promising new treatment methods. It must be noted, however, that the safety and efficacy of these clinical trial treatments are uncertain.
As outlook and treatment are affected by the stage at which mesothelioma is diagnosed, be vigilant in seeking medical attention early and throughout your life. If you have a history of asbestos exposure, see your doctor and convey your experiences. If you are diagnosed with mesothelioma, maintain a positive outlook, buoyed by the support of the medical community and of other mesothelioma patients, and by the knowledge that others have survived mesothelioma.
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US mesothelioma patterns 1973-2002: indicators of change and insights into background rates.
Mesothelioma rates are declining toward background levels, although estimates of the background rate have varied. We expanded upon earlier analyses and provided a data-based estimate of the background rate. We analyzed US male and female patterns for five age groups using the National Cancer Institute's Surveillance Epidemiology and End Results registry data from 1973 to 2002. Age-specific and age-adjusted incidence rates per 1 000 000 persons per year, standardized to the 2000 US population, were calculated for total, pleural, and peritoneal mesothelioma. We also calculated rates for persons who attained working age after the US Occupational Safety and Health Administration asbestos exposure limits took effect. Mesothelioma rates observed among young males and females varied little over time. We observed a decline and convergence of recent male and female rates in older age groups, except those who are between the age of 60 and above, for whom the 2002 male rate was approximately five times greater than that of females. As expected, rates were higher in major shipyard areas on the West coast. Rates for persons with little or no opportunity for occupational asbestos exposure were 1.15 (95% confidence interval: 0.90-1.45) for men and 0.94 (95% confidence interval: 0.87-1.24) for women. Mesothelioma is rare in younger age groups, and rates have been relatively stable and similar for both sexes. Rates continue to decline in older age groups, but remain high for males at 60 years or older. Rates among females at older ages suggest an impact of occupational exposure. The background rate for persons below age 50 is approximately one per million, independent of sex. Future data are needed to estimate this rate for older age groups.
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