Pleural Mesothelioma
Category cancers, cancer treatment.
Keywords: Cancer Patient
What is the mesothelial tissue?
Mesothelioma is a protective sac (membrane) that covers and protects most internal organs of the body. It consists of two layers of cells covering the body layer and a second layer forms a sac around it. Mesothelioma produces a lubricating fluid that is released between these layers, allowing moving organs (such as lungs) to move easily. The area between the two layers is called the pleural space. Mesothelial tissue found in the lining of the abdominal cavity, lungs, testes, and heart.
EC is mesothelioma?
Pleural mesothelioma is an aggressive cancer, although rare in the general population, are the most common pleural neoplasia. Mesothelioma occurs when mesothelial cells grow in an uncontrolled way. It also includes those cells lose their ability to stop production of lubricating fluid when it is enough. This results in encapsulation of bodies in a thick layer of tumor tissue and excess fluid, which eventually will cause simpotme. These cells can grow and invade other organs, and may spread to other areas of the body. When cells spread in the body metastasis occurs.
Mesothelioma are primitive serous tumors derived from the mesothelial cells of the wrapper and is often presented with pleural headquarters (65-70% common tumor of the pleura me) sometimes peritoneal (30-35%) and less frequently in the pericardial or vaginalei testis.
Risk Factors
Mesothelioma is a rare type of cancer, with about 2,000 cases diagnosed annually in the United States. The incidence in the general population is 15 cases per 1 million men and 2 cases per 1 million women. In Britain and Germany incidence is 1.25 cases / 100,000 inhabitants / year and 1.1 respectively cazuri/100.000 inhabitants / year. Ratio M / F is 8:1, male predominance is explained by occupational exposure (65-94% patients), while in women the exposure is mainly due to the domestic environment (6-35%), especially occupational exposure to asbestos. The risk increases with age. The biggest risk factor for developing the disease is occupational exposure to asbestos, the responasbil for 70-80% of cases. This can happen in buildings with asbestos-based material in plants in which this material in mines, construction sites. Asbestos is a material important physical properties used in thermal insulation of buildings, housing, ceilings, cement and even in certain parts of vehicles.
The average age of diagnosis of the disease is around 60 years, most patients were men who worked in construction, the shipyards, the railways, mining and automotive industries. Because asbestos dust can wear and carry clothes, unintentionally expose these workers and their families at risk of developing pleural mesothelioma.
Before exposure to known risk azebest, miners and people who were exposed to asbestos working without protective equipment. Since 1970, Protection and Health Administration U.S. Occupational (OSHA) imposed limits on exposure to asbestos and providing protective equipment at work.
80% of pleural mesothelioma cases occur in people who were exposed to asbestos, however, only 10% of those with a history of asbestos exposure develop the disease increased. This suggests that additional exposures or other factors are involved in disease development. Even more surprising is that 50% HP teeth people with pleural mesothelioma have a history of asbestos exposure.
Pleural mesothelioma is detected in 20-40 years after exposure to asbestos. This exposure has occurred, usually over a period of time, but was reported as lasting 1-2 months.
Although a very high number of patients have a very long history of smoking, experts are reluctant to criminalize smoking in the development of this particular type of cancer.
Malignant mesothelioma has been linked with the development of medical imaging or radiotherapy application (for treating other types of cancer). Also, scientists have recently suggested the existence of a correlation between exposure to simian virus 40 and subsequent development of cancer. However, studies tend to present as a carcinogenic virus and not as an agent able to induce this neoplasia through individual action.
The incidence of mesothelioma varies in different parts of the world, according to the period in which asbestos was used widely in the area. Rates are high in the UK, where they recorded 1800 cases / year. Incidence consider the number of cases and population size. This is because asbestos utilizearea in Western Europe remained at their peak by 1980, while the peak of asbestos exposure in the United States took place between 1930-1960. Australia was one of the world's largest producers of asbestos, which resulted in the highest incidence of mesothelioma in the world (reported in population size). In the United States the incidence rate started to decrease, while Europe and Australia are expected constant level for the next 10-15 years before they begin to decline.
Following the ban on use of asbestos in many countries asbestos manufacturers began to promote sales of their products in developing countries in Asia and Latin America. Experts fear that the peak incidence in these countries will come, and will be similar situations encountered in the United States and Europe.
How can it be prevented pleural mesothelioma?
Pleural mesothelioma risk decreases with decreasing exposure. Workers who are exposed to asbestos at work should wear protective clothing and masks, you must change clothes before leaving the workplace and avoid transport of particles and asbestos dust home.
What screening tests are available?
There are good programs screening for pleural mesothelioma. Imaging studies (radiographs and CT scans) are not sensitive enough to detect tumors before symptoms appear.
What are mesothelioma signs?
The tumor usually occurs in the lower regions of the mediastinum, the pleura of the lung bases, and may extend lower and diaphragm comprising neoplastic process. As the disease progresses, expand reach and lung parenchyma, chest wall and mediastinum, sometimes even in the esophagus, ribs, vertebrae, brachial plexus or superior vena cava.
Tumor evolution is quite long and starts as small node, which will expand over time, including free zones around them.
Symptoms of pleural mesothelioma are caused by an accumulation of tumor tissue that surrounds the lungs and fluid in the pleural space that prevents the lungs to expand to its full capacity. This causes pressure on the lungs and difficulty breathing. As the disease progresses, patients may lose weight and have a dry cough. Fluid in the abdominal cavity and tumor tissue cause pain, weight loss, and abdominal bloating.
Nonpleuritică dyspnea and chest pain are the most common complaints for malignant mesothelioma. Approximately 60-90% of patients present with these symptoms to the doctor. Over 50% of patients there and pleural effusion (accumulation of fluid in the pleural space pathology).
In some cases the patient may be long asimpotmatic and pleural effusion, or local changes in the lung can be observed from performing routine investigations, or to diagnose other diseases.
Diagnosis and staging of mesothelioma
Diagnosing mesothelioma is relatively difficult because signs and symptoms are nonspecific. It is therefore very important that history be made carefully, because recognizing a patient's exposure to asbestos may focus so much history diagnosis. Mesothelioma are found mainly in the pleura, especially on the right (in 90% of cases), but also in the peritoneum (5%), pericardium (0.5%).
Physical examination is very important because the obedience and chest percussion can identify the presence of pleural effusion. Distinguishing marks appear only in very few cases, when the tumor is so advanced that determine cardiac compression, brachial plexopathy, Homer syndrome or superior vena cava syndrome.
Patients experiencing worrying symptoms of pleural mesothelioma may make X-rays, showing they have fluid in the pleura. Thereafter, these patients will perform CT for further evaluation of cancer. If abdominal mesothelioma, a CT scan is done to see the abdominal anatomy.
If it shows the existence of a pleural effusion is very important that the purpose of puncture to harvest liquid that can then be analyzed. Although fluid cytology may be positive in many cases, there is the possibility that it does not provide useful information and might help diagnosis. It is important to note that the severity of the patient's condition and prognosis are not influenced by the amount of pleural effusion present.
To confirm the diagnosis a biopsy should be performed. to obtain a tissue sample is introduced into the lung, among ribs, a thoracoscope. If mesothelioma abdomional to obtain a sample of tissue is used peritoneoscop inserted into the abdomen.
Staging refers extent of disease and disease stage determines the treatment to be followed. Doctors use staging system TNM (tumor-node-metastasis system). It describes the size of the tumor, whether lymph nodes are involved, and that has spread to other parts of the body (metastasize). All they give is between stage I-IV. Patients with early stage tend to live longer and respond better to treatments available.
What are the treatments for mesothelioma?
Treatment depends on the stage of disease, tumor location, patient's age and general health statrea. Younger and healthier patients with early stage disease may be candidates for surgery that removes the mesothelial tissue surrounding the tumor. This operation is extensive, and still do not know how many benefits to the patient.
Traditional radiation therapy is used in some cases after surgery, but healing of cancer can affect healthy lung tissue and can lead to toxicity whose negative effects are greater than the benefits of radiotherapy. Researchers seek to find ways to manage radiation directly on the tumor, using implants or UV light therapy.
Also for the treatment of patients with mesothelioma chemotherapy was used, but until now not known exactly benefits of this therapy. Today we know that chemotherapy can bring significant improvements in symptoms. Chemotherapeutic agents used either alone or in combination are: Cisplatin, Carboplatin, Mitomycin, vinblastine, gemcitabine and anthracycline agents (doxorubicin). These drugs had responses in 10-20% of cases.
A recent clinical trial randomized patients divided into two groups: one group and the other group received cisplatin cisplatin in combination with pemetrexed (Alimta). Patients who received combination chemotherapy had higher response rates have lived longer and had fewer side effects. In addition, researchers found that taking folic acid and vitamin B12 with combined chemotherapy resulted in decreased toxicity without compromising therapy effectiveness. This scheme is now considered the standard of care for mesothelioma that can not be treated by surgery.
Researchers enterprises studies on chemotherapy directly into the pleural space. But so far the results of these studies have been disappointing.
Because current therapies have limited effectiveness, researchers continue to look for new ways to treat mesothelioma. Some of the treatments that are currently being studied include: interleukin-2 (a biotherapy), lovastatin (a cholesterol-lowering medicine), immunotherapy, genoterapia (a method that attempts to correct abnormal genes that cause cancer), photodynamic therapy ( Photodynamic therapy uses a laser to activate a photosensitizing drug during surgical resection). Patients should talk to their doctors about clinical trials available pentro mesothelioma.
A problem is patients may experience a recurrence of fluid into the pleural space / this fluid can be distant with a chest tube (a tube that is inserted into the chest cavity and left in for a period of time to allow drainage) or using a procedure called thoracentesis. Diagnostic and therapeutic thoracentesis is a procedure that drains fluid from the pleural cavity pleurisy. Pleurisy is a common complication of lung cancer and such a procedure is relatively often. The liquid can contain substances that suggest neoplastic nature and even malignant cells. Thoracentesis is performed by inserting a needle into the pleural space, needle connected to a drain that will drain fluid after fluid drainage needle will be removed. In many cases, Track operation is followed by another procedurp called pleurodeză. This therapeutic procedure or drug injecting a chemical (talc, bleomycin) in the lungs to create local inflammation in the lungs and inside nivelulsuprafeţei chest. This causes adhesion between the surface of the lungs and chest, thus preventing the formation of fluid in the pleural cavity.
If mesothelioma abdominal fluid drainage procedure is called paracentesis. This procedure uses a needle (drain tube) that is inserted into the abdomen, the space umlut fluid to drain it.
If the presence of fluid is a chronic probelmp, then patients may be inserted into the catheter in the chest with a semi-permanent nature, allowing them to drain fluid if necessary alone, sitting at home.
Fluid drainage improves breathing and chest pain which is caused by the formation of fluid.
FOLLOW
Patients will be followed by doctors by physical examination, chest X-ray and CT.
