Papillary Mesothelioma

Papillary mesothelioma, also known as well-differentiated papillary mesothelioma (WDPM), is an uncommon variation of epithelioma mesothelioma. It is frequently diagnosed in women, generally those who are still in the reproductive stages of their life, but it has also been clinically diagnosed in men as well.
The disease usually develops in the peritoneum - the lining of the abdomen - and, in most cases, is benign. Papillary mesothelioma, however, has also been seen to have origins in the tunica vaginalis, part of the male reproductive system as well as in the pleura or the lining of the lungs.
Papillary mesothelioma tumors generally cause no pain and the mesothelioma prognosis for someone diagnosed with such a tumor is usually very favorable. Unlike malignant mesothelioma of various types, however, this kind of mesothelioma cannot be definitively linked to asbestos exposure though a connection has been made in some cases.
Because the occurrence of this disease is quite rare, there is no standard mesothelioma treatment at this time. Past reports have shown that mesothelioma doctors who do encounter WDPM have offered surgical removal of the tumor as a possible treatment and others have shrunk the tumor with mesothelioma chemotherapy or radiation. However, it is rare that this kind of tumor spreads to other parts of the body, so mesothelioma surgery is usually the preferred option. Reoccurrence of the disease does happen in many cases but is not an indication that the patient will later develop a malignant form of mesothelioma cancer.

Sources

Hoekstra, A., Riben, M., Frumovitz, M. et al. Well-Differentiated Papillary Mesothelioma of the Peritoneum: a pathological analysis and review of the literature. (2005). Gynecologic Oncology; 98(1): 161-167
http://www.ajronline.org/cgi/reprint/155/6/1245.pdf

Biphasic Mesothelioma

Biphasic mesothelioma is the second most common cellular form of this disease, accounting for 20 to 40 percent of all known cases. As the name implies, biphasic mesothelioma is a mixture of two mesothelioma cell types.

Characteristics

Unlike the more common epithelioid type, biphasic mesothelioma cells lack a specific structure. This type of mesothelioma is a mix of epithelioid and sarcomatoid cells. Whereas the former has a clearly visible nucleus and is found in uniform, organized arrangements and tend to be of a single shape, sarcomatoid cells are more oval or oblong shaped and have no easily identifiable nucleus. Although both mesothelioma types are present in a biphasic tumor, they have a tendency to form in differentiated groups; they are not usually found in the same area of the tumor.

Diagnosis and Treatment

Mesothelioma cancer is exceptionally difficult to diagnose, which is why a mesothelioma diagnosis is usually not made until stage 3 mesothelioma or stage 4 mesothelioma is reached. It is important to confirm a history of asbestos exposure, as mesothelioma symptoms are similar to a wide range of respiratory illnesses.
Mesothelioma doctors usually take an x-ray; if there is cause for concern, the patient is referred to a radiology lab, where more advanced images are taken. If abnormal areas are discovered, a tissue sample, or biopsy is taken to confirm the diagnosis.
A recent test developed by a Japanese biotech company, called MESOMARK™, may help pathologists in diagnosing mesothelioma at an earlier stage, when it is most treatable.
Treatment in most cases is limited to palliative ones, since the disease is usually diagnosed too late for mesothelioma surgery. Mesothelioma is usually treated with a multi-modal therapy involving a combination of radiation and chemotherapy; surgical techniques may be used to relieve the symptoms, but in the later stages are usually not effective in treating the disease.

Sources

Dodson, R. and Hammar, S. Asbestos: Risk Assessment, Epidemiology, and Health Effects. (Boca Raton: Taylor & Francis, 2006).
Pass, I., Vogelzang, N., Carbone, M. Malignant Mesothelioma: Advances in Pathogenesis, Diagnosis, and Transitional Therapies. (New York: Springer, 2005.)
Galateau-Salle, Francoise. Pathology of Malignant Mesothelioma. (London: Springer-Verlag London Limited, 2006).
Bruce, W., Robinson, A., & Philippe Chahinian. "Mesothelioma". Informa Health Care, 2002. (ISBN 9058231801)

Sarcomatoid Mesothelioma

Mesothelioma is a cancer that attacks the lubricative layer lining the inside of the chest and abdomen and the internal organs. Pathologists categorize mesothelioma cancer cases according to levels of criteria, which are as follows:
Location:

• Lungs (pleural mesothelioma)
• Abdomen (peritoneal mesothelioma)
• Heart (pericardial mesothelioma)

Stage:

• Stage 1 Mesothelioma - Cancer cells have started to form
• Stage 2 Mesothelioma - Cancer has spread locally
• Stage 3 Mesothelioma - Cancer has spread to adjoining areas
• Stage 4 Mesothelioma - Cancer has begun to metastasize

Cellular Structure:

• Epithelial (organized and structured)
• Sarcomatoid (random and irregular)
• Biphasic (a mix of epithelial and sarcomatoid)
• Desoplastic (a variation of the sarcomatoid variety)

Cellular structure is determined by an actual visual examination of the cells under a microscope.

About Sarcomatoid Mesothelioma

Sarcomatoid Mesothelioma accounts for approximately 10 to 15 percent of all diagnoses. The mesothelioma cell types in this case are elongated and spindle-shaped, and are arranged in a rather haphazard way. Sarcomatoid cells also lack a nucleus, unlike epithelioid cells, which have clearly visible nuclei.
The desoplastic variety of sarcomatoid mesothelioma is difficult to distinguish from healthy tissue in many cases, making an accurate mesothelioma diagnosis challenging.

Diagnosis

Once mesothelioma symptoms have been cataloged and a history of asbestos exposure determined, the next step is to look inside the body - initially with x-rays, followed up by more sophisticated imaging such as CT scans or MRIs. If these images reveal serious abnormalities, a biopsy (tissue samples) will be ordered. These are examined and analyzed at a lab, which usually confirms or contradicts the diagnosis.
When it comes to the sarcomatoid mesothelioma, traditional methods of biopsy pose additional challenges; the normal "needle core" method often results in false information, as sarcomatoid cells are often similar in appearance to benign fibrous tissue. Additionally, histological methods of diagnosis often make it difficult to distinguish between sarcomatoid mesothelioma and other types of unrelated sarcomatoid cancers.
A precise and accurate diagnosis is vital, because a misdiagnosis can lead to an inappropriate course of mesothelioma treatment being prescribed; it is a good idea to get a second and even a third opinion if mesothelioma is suspected.

Treatment Options

Although the details will differ depending on the individual case, all forms of cancer are treated through some combination of surgery, radiation therapy, and chemotherapy. How these are administered depends on the location and stage of the cancer.
Unfortunately, sarcomatoid mesothelioma is notoriously resistant to treatment, and the mesothelioma prognosis is not good. The average mesothelioma survival rate between diagnosis and death is seven months.

Source

Hammer, Samuel P. "Macroscopic, Histologic, Histochemical, Immunohistochemical, and Ultrastructural Features of Mesothelioma." Society of Ultrastructural Pathology Companion Meeting, 27 February 2005, http://sup.ultrakohl.com/Uscap/uscap05/meso1.pdf

Epithelial Mesothelioma

Epithelial mesothelioma cells have a definite structure with visible nuclei. This is the most common variant of this type of mesothelioma cancer, accounting for about 60 percent of all cases. This type of mesothelioma develops when malignant cells develop on any of the mesothelial linings. When examined under a microscope, these mesothelioma cell types are of a uniform size and shape, and resemble normal, healthy epithelial cells.
Epithelial mesothelioma cells also bear a strong resemblance to adenocarcinoma cells, which are also associated with lung tissue. Patients who have been diagnosed with adenocarcinoma should also be examined for mesothelioma diagnosis as well.

Variants

Papillary mesothelioma is an example of epithelial mesothelioma; other variants include any of the following:

• Signet Ring
• Single File
• Adenoid Cystic
• Glandular
• Tubulopapillary
• Histiocytoid
• Microcystic
• Macrocystic
• Glomeruloid

• Diffuse - NOS
• Small Cell
• Deciduoid
• Pleomorphic
• In Situ
• Mucin Positive
• Well-Differentiated Papillary
• Gaucher Cell-Like

What differentiates these various types are the shape, size and formation of the cells. This can determine what course of mesothelioma treatment is appropriate for the patient's situations.

Epithelial Mesothelioma and Asbestos

Once asbestos fibers are inhaled, they become lodged in the lung tissue, where they remain indefinitely. Mesothelioma is associated with hard, crystalline amphibole asbestos, which consists of hard, needle-like fibers that literally bore through lung tissue over time, causing chronic inflammation that ultimately results in malignancy. The mesothelioma latency period, can be anywhere from five to seventy-five years. Mesothelioma symptoms are similar to those of other respiratory illnesses, which is why a mesothelioma diagnosis has historically been so difficult to make.

Sources

Dodson, R. and Hammar, S. Asbestos: Risk Assessment, Epidemiology, and Health Effects. (Boca Raton: Taylor & Francis, 2006).
Pass, I., Vogelzang, N., Carbone, M. Malignant Mesothelioma: Advances in Pathogenesis, Diagnosis, and Transitional Therapies. (New York: Springer, 2005)

Benign Mesothelioma

Malignant mesothelioma is an unusual form of cancer in that it usually remains latent in the body for 20-50 years before it appears. However, benign or non-malignant mesothelioma cancer can surface much sooner and is often an indication that the individual should be carefully watched for signs of more serious asbestos-related diseases in the future.
Benign mesothelioma is much easier to treat than the malignant form and can indeed be treated successfully. This type of asbestos cancer also differs from the malignant form in that benign tumors do not invade nearby tissues nor spread to other parts of the body. The fact that it remains contained makes it much easier to address and mesothelioma surgery may be recommended. However, these benign tumors can grow to be quite large and may indeed negatively impact the organs of the body that are close to the tumor, causing a host of other problems if not immediately addressed.
Non-malignant mesothelioma, for the most part, causes many of the same symptoms as malignant mesothelioma so, at the offset, it is difficult to distinguish the two with just a simple examination. Mesothelioma symptoms may include dry cough, difficulty breathing or shortness of breath, and chest pain. After the initial examination, mesothelioma doctors will most likely order a simple chest x-ray followed by more sophisticated imaging tests that may include a CT scan or MRI. A biopsy will be part of this battery of tests as well, if a mesothelioma diagnosis is suspected after the scans. The biopsy can definitively determine whether or not the tumor is malignant.
Once diagnosed, benign mesothelioma is usually treated with a surgical procedure known as a thoracotomy. This type of mesothelioma treatment involves the removal of one segment of the lung or, in very rare cases, the entire affected lung. As with any surgery, complications may occur, but the mesothelioma survival rate is generally higher in these patients.

Sources

Advanced Cancer Help
advancedcancerhelp.com/benign_mesothelioma.htm
Cancer Research UK. About Mesothelioma
www.cancerhelp.org.uk/help/default.asp?page=4393

Malignant Mesothelioma

Malignant Mesothelioma is a rare form of cancer that affects the thin cell wall lining of the body's internal organs and structures. This lining is known as the mesothelium. Malignant mesothelioma has three known varieties. They are malignant pleural mesothelioma, malignant pericardial mesothelioma, and malignant peritoneal mesothelioma. Pleural mesothelioma occurs in the pleura, the lung's lining. Peritoneal mesothelioma occurs in the peritoneum, the abdominal cavity wall. And pericardial mesothelioma occurs in the lining of the hearth, known as the pericardium.

What Causes Malignant Mesothelioma?

Mesothelioma is known only to be caused by asbestos exposure. Asbestos is a nature, yet toxic mineral that was used commonly in heavy industry. Microscopic asbestos fibers enter the body through the lung or ingestion. Once inside, the durable fibers are unable to be broken down or expelled by the body, causing a harmful inflammation and scarring of the mesothelium. This scarring lays the groundwork for malignant mesothelioma and other respiratory conditions, such as asbestosis.
There is a great deal of latency associated with asbestos exposure and the onset of mesothelioma. Often patients will not encounter mesothelioma symptoms until 30-50 years following exposure to asbestos. In many cases, those diagnosed with mesothelioma are not those who were directly exposed to asbestos in a jobsite setting. Spouses and children of those exposed to asbestos who frequently came into contact with the fibers on the clothing or person of those exposed have also developed malignant mesothelioma as a result.

How is Malignant Mesothelioma Treated?

Malignant mesothelioma prognosis is poor, as often the disease will be diagnosed in its later stages after symptoms have appeared. However, there are several treatment options for the management of the cancer. Among these are mesothelioma chemotherapy, radiation therapy, and surgical resection. Chemotherapeutic and radiation therapy methods are more likely but surgery is often an option for those whose disease is diagnosed early enough.
More aggressive therapies are now possible for patients with mesothelioma diagnosed in its earlier stages. For instance, extrapleural pneumonectomy is now possible in many pleural mesothelioma patients who are deemed eligible for aggressive surgery. Extrapleural pneumonectomy involves the removal of the entire affected lung, the pericardium, the pleura, and the diaphragm. This aggressive surgery is performed frequently in early stage mesothelioma patients by Dr. David Sugarbaker at the Brigham and Women's Hospital in Boston, MA.
Patient's who are eligible to receive an aggressive surgery, like an extrapleural pneumonectomy, will have a far more favorable prognosis than those diagnosed with advanced stage inoperable disease. However, there are treatment options for nearly all mesothelioma patients. Chemotherapy cocktails such as the use of Alimta® in conjunction with Cisplatin, as well as numerous other clinical trial being carried out give mesothelioma patients the ability to slow the advance of the disease and extend survival rates.

Malignant Pleural Mesothelioma

Malignant pleural mesothelioma is the most common type of mesothelioma and occurs in the mesothelial membrane surrounding the chest cavity and lungs. Pleural mesothelioma, because it is more common than other varieties of the malignancy, has had more research invested in it. Pleural mesothelioma represents approximately 70% of all mesothelioma diagnoses.

Malignant Peritoneal Mesothelioma

Malignant peritoneal mesothelioma is less common than pleural mesothelioma and represents approximately 15-20% of all mesothelioma diagnoses. Peritoneal mesothelioma occurs in the lining of the abdominal cavity in the membrane surrounding the organs of this region. Like pleural mesothelioma, peritoneal mesothelioma is known only to be caused by exposure to asbestos.

Malignant Pericardial Mesothelioma

Malignant pericardial mesothelioma is among the rarest of all known malignancies, and represents less than 10% of all mesothelioma diagnoses. Pericardial mesotheliomas occur within the mesothelial lining of the heart. Pericardial mesotheliomas, like those of pleural and peritoneal varieties, are associated with asbestos exposure. Pericardial mesotheliomas differ from the pleural variant in that they are known to occur in younger individuals. While surgery is seen as the preferred method of treatment, mobidity and mortality are almost certain given the region in which the tumor is located.

How is Malignant Mesothelioma diagnosed?

Malignant Mesothelioma will typically be suspected if the patient complains of chest pain, difficulty breathing, shortness of breath, chronic cough, or difficulty swallowing. While any of these could indicate mesothelioma, they are also associated with many other respiratory conditions so further diagnostic procedures are typically warranted before an accurate malignant mesothelioma diagnosis can be made. These may include imaging scans, such as computer topography or magnetic resonance imaging. A diagnostic biopsy is also required for cancer specialist to examine the behavior of these cells before a diagnosis is determined.
Misdiagnosis is not uncommon in patients of the malignant mesothelioma, because the disease's symptoms so closely resemble those of other related conditions, including lung cancer, and other respiratory ailments. For this reason those who are at high-risk of mesothelioma (including those with asbestos history) should consult with physicians and cancer centers well versed in the treatment and diagnosis of malignant mesothelioma.

What options do patients of Malignant Mesothelioma have?

Unfortunately, many of those diagnosed with malignant mesothelioma have incurred illness as a result of a negligent exposure to asbestos. It is now clear that many asbestos manufacturers were well aware of the hazards of asbestos and asbestos exposure. Hundreds of thousands of laborers and workers have been exposed in shipyards, power plants, factories, and other jobsites- thousands of which develop malignant mesothelioma each year.
Patients of malignant mesothelioma or any other asbestos related health complications should consult their physician regarding the many mesothelioma treatment options that are available.  Also, patients may be eligible for compensation if they were wrongfully exposed. All those seeking further information should fill out the brief contact form on this page to receive a mesothelioma and asbestos information packet detailing treatment and legal options.

Source

National Cancer Institute - Malignant Mesothelioma
http://www.cancer.gov/cancertopics/types/malignantmesothelioma

Pericardial Mesothelioma

Malignant mesothelioma is a type of cancer that originates in the mesothelium, a thin wall of cells that surround the body's organs and internal structures. Pericardial mesothelioma originates in the lining of the heart. Other locales of the disease are malignant pleural mesothelioma, which occurs in the lining of the lungs and malignant peritoneal mesothelioma, which occurs in the abdomen wall. Pericardial mesothelioma is the rarest of these malignancies and accounts for only an estimated 10 percent of all mesothelioma incidences annually.

What Causes Pericardial Mesothelioma?

Pericardial mesothelioma is an asbestos cancer, meaning it's only known cause is asbestos exposure. Asbestos is a naturally occurring, but toxic, mineral that was used in industrial capacities. While the precise route by which microscopic asbestos fibers reaches the pericardial lining is not known, mesothelioma doctors surmise that inhaled asbestos fibers are absorbed into the bloodstream and become entangled in the heart's lining as the blood processes through the heart. Malignant mesothelioma occurring in other parts of the body, such as in the pleura or peritoneum, can also metastasize to the pericardial lining.

How is Pericardial Mesothelioma Treated?

Prognoses are poor in cases of pericardial mesothelioma, just as nearly every mesothelioma prognosis is. However, several treatment options exist to help patients manage the disease and maintain comfort. Chemotherapy and radiation therapy are the most likely mesothelioma treatment options for patients of this disease. Mesothelioma surgery is typically not an option because of the location of the disease and the risk of grave damage to the tumor area.

How is Pericardial Mesothelioma Diagnosed?

Physicians will often suspect pericardial mesothelioma diagnosis if the patient has trouble breathing, shortness of breath, or chest pain. A comprehensive diagnostic and biopsy process will be undergone through use of multiple body imaging scans.

What are a Patient's Options?

Patients of pericardial mesothelioma may be eligible for financial compensation if they were wrongly exposed to asbestos. Anyone who worked with asbestos products is potentially at-risk and should fill out the brief form on this page to receive additional treatment and legal information.

Source

PubMed Central
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=325154