There are four different types of mesothelioma, and within them, there are different classifications of cells. Almost all of them, however, are caused by asbestos exposure, which usually happens in the workplace. If it is suspected that the patient has mesothelioma, the physician will look back through the patient’s professional history to determine whether there is a possibility that asbestos exposure took place. Mesothelioma has a very long latency period, which is usually between 10 and 50 years, so patients might quite a long way have to look back.

The Four Types of Mesothelioma

Pleural mesothelioma is the most common type of the cancer. In most cases, people can remember that they did indeed breathe in asbestos. The second most common type is peritoneal mesothelioma, which happens in the lining of the abdomen. This happens when fibers are swallowed. The other two types are pericardial mesothelioma (on the lining of the heart) and testicular mesothelioma (on the lining of the testes), and it is not clear what the link between asbestos and these two types are.

The Signs and Symptoms of Mesothelioma

Mesothelioma is mainly asymptomatic due to its lengthy latency period. By the time that people affected do notice symptoms, the disease is often already quite advanced. As a result, the prognosis is also very poor. Usually, people observe some mild pain in the area that is affected and feel fatigue. However, once the disease becomes more advanced, symptoms become more pronounced as well. They include:

• Chronic pain at the tumor site
• Shortness of breath
• Fluid buildup
• Unintentional weight loss
• Bowel obstruction

Joint pain is not commonly a symptom of mesothelioma, although there is a significant exception, which is benign mesothelioma.

Benign Mesothelioma

Benign mesothelioma is incredibly rare, and is a noncancerous form of the disease. It is not understood what the causes of this form of cancer are. However, the prognosis is very positive and surgery is usually all that is needed to cause a patient to be in remission.

Benign mesothelioma is not believed to be related to asbestos exposure, nor is it cancerous. Malignant mesothelioma usually starts to appear after a 20 to 50 year latency period, and therefore usually occurs in people who are quite elderly. In contrast, benign mesothelioma can occur at any age and in any person.

There are different types of benign mesothelioma, all of which are rarer than malignant mesothelioma. The types are:

• Benign multicystic peritoneal mesothelioma (BMPM). Only 153 cases have been reported to date in medical literature. It usually happens in the pelvis and is most common in women, although men and children can also develop it. Patients usually present with abdominal swelling and pain.
• Well-differentiated papillary mesothelioma (WDPM). Only 60 cases have been reported to date in medical literature. While generally benign, some patients have had a number of malignant cells in them as well. This tumor usually happens in the abdominal cavity and is most common in women between the ages of 30 and 40. Rarely, it is found in the vaginalis (testicular lining), pleura, or heart sac. Symptoms include fluid accumulation (effusions) and pain.
• Adenomatoid tumor (AT), which is usually in the uterus wall or the tunica vaginalis.
• Localized fibrous tumor (LFT), which is found mainly in the pleura, although it can be found in the peritoneum, tunica vaginalis, or pericardium. Fifty percent of those diagnosed with LFT do not have symptoms. Those that do, however, may experience breathlessness, pain, and coughs.

It should be noted that WDPM has an increased chance of becoming a malignant cancer.

The mortality rate of malignant mesothelioma is incredibly high, with fewer than 8% of those diagnosed surviving past the five year point. With benign mesothelioma, by contrast, full recovery is possible following surgery. However, some people who have been diagnosed with benign mesothelioma find that their tumors recur and it is possible for this relapse to be malignant. Hence, once someone has been diagnosed with benign mesothelioma, they will be monitored for life.

It is very important to understand that the chance of a mesothelioma cancer being benign is incredibly rare. Usually, the cancer is malignant and will have started to spread to other locations, which makes it a very dangerous cancer. However, there is a small chance of the cancer being benign, in which case it spreads very slowly and usually doesn’t affect any other organs either. They can, however, grow very large in size and this can lead to complications. As it is a type of mesothelioma, however, it is common for people not to be aware that they have it.
In most cases, benign mesothelioma starts in the abdomen, usually in people who do not have an asbestos exposure history. If the tumor is larger than 7cm, around 20% of people star to experience symptoms. These symptoms include:

• Seizure
• Coma
• Low blood sugar
• Painful swelling of the joints and bones

Benign mesothelioma is most common in women around their middle age. It is the only form of mesothelioma that can affect the joints. The tumors grow as a single mass, which is a significant difference with the malignant type, where many small nodules start to appear. Because it is often a single tumor, it is also much easier to surgically remove it. Once removed, the symptoms associated with benign mesothelioma disappear as well.

In terms of treatment, a surgical procedure is usually required in order to remove the tumor. No follow up treatment, such as radiotherapy or chemotherapy, is required. This is because it is not a cancerous type of growth and it does not spread. Some 75% of benign mesothelioma patients develop their tumors in the lung. As a result, the most common treatment surgery is the thoracotomy, although this does depend on the location and size of the tumor. During the procedure, a piece of the lung may be removed, or a lobe. In rare cases, the entire lung is surgically removed.

The tumor is, in the grand scheme of thing, harmless. The surgery, however, is not. In fact, quite a few people experience pleural effusions as a result, which means fluids start to develop in the spaces of the lung, leading to pressure on the heart and lungs. Usually, patients are provided with a chest drain that will remain in place for a few days after surgery. This will help to avoid effusions.

Prognosis is very good. Ninety percent of people do not have a repeat occurrence after surgery. The few symptoms that people experience with benign mesothelioma, including joint pain, tend to disappear in full following the surgical procedure.