Pericardial Mesothelioma
Types of mesothelioma are caused by asbestos, medical experts are still researching how asbestos manages to reach the pericardium.
Pericardial mesothelioma is one of the most difficult types to treat because of the delicate location of tumor growth within the lining of the heart. The pericardium consists of two layers:
- The outer layer is known as the parietal layer or heart sac.
- The inner layer is called the visceral layer or epicardium.
Like the other types of mesothelioma, pericardial mesothelioma has a long, 50-70 year latency period and is usually diagnosed in its later stages, often making for a poor prognosis.
Causes of Pericardial Mesothelioma
Prolonged exposure to asbestos is the only known cause of of most mesothelioma cancers, including pericardial mesothelioma — though the causal relationship in this case is less clear.
Generally speaking, loose asbestos particles are inhaled and gather in or near the internal organs. It is unclear, however, as to how an individual develops pericardial mesothelioma and how the dangerous asbestos fibers make their way into the pericardium. Researchers theorize that asbestos fibers, once they are broken into smaller pieces in the lungs, are carried from the lungs into the bloodstream. As the fibers are pumped through the heart, they may become lodged in the heart lining.
Once lodged in the pericardium, chronic inflammation leads to the formation of cancerous cell growth, thickening of the heart lining, and tumors, similar to what occurs in the more common pleural mesothelioma.
Symptoms of Pericardial Mesothelioma
A majority of patients exhibit no symptoms at the onset of pericardial mesothelioma. When symptoms are present, it’s difficult to distinguish them from more common illnesses, such as heart disease. As with both the pleura and the peritoneum, the growth of tumors in the pericardial region causes the expansion of tissue and allows fluid to accumulate around the heart. The fluid and thickened membrane increases pressure, interfering with the functioning of the heart. It is this fluid that is responsible for most of the symptoms of pericardial mesothelioma. These symptoms include:
- Chest pain, ranging from uncomfortable to severe
- Shortness of breath or difficulty breathing
- Heart palpitations or an irregular heartbeat
- Persistent coughing
- Extreme fatigue after minimal activity or exertion
Pericardial mesothelioma resembles the other types of asbestos-caused mesothelioma in that the symptoms are often mistaken for something more common. In this case, heart attack or some other sort of heart disease is suspected, especially when the patient begins complaining of persistent chest pains. Other common heart illnesses pericardial mesothelioma has been mistaken for include:
- Tuberculosis pericarditis
- Constrictive pericarditis
- Cardiac tamponade
- Intra-atrial myxoma
- Cardiomyopathy
Symptoms can vary with each patient and can be affected by a number of variables, including:
- Location and size of the tumors
- Overall health of the patient
- Age of the patient
A thorough patient history is the key to the proper diagnosis of the disease. Anyone who worked with asbestos or asbestos-containing products, particularly in shipyards or in the construction field, should always mention their exposure to their doctor. Because this is a rare disease, other diagnoses are usually considered before doctors investigate the possibilities of mesothelioma.
Diagnosis
All forms of mesothelioma are often difficult to diagnose, including pericardial. After assessing symptoms, medical history and current health, a physical examination is performed. Then, imaging tests and a biopsy are performed to locate the tumors and determine whether they are benign or malignant.
Imaging
The traditional x-ray gives doctors a cursory glance at the heart. Because the diagnostic abilities of traditional x-rays are limited, doctors will usually order a more sophisticated test that gives them a better look at the internal organs, such as a CT scan or MRI.
The CT scans and MRIs can lead doctors to their next step in diagnosing the disease. If these tests seem to indicate the presence of mesothelioma, the physician will most likely order a tissue biopsy.
Biopsy
A biopsy is a medical procedure that uses a thin needle to remove tissue from the affected area. In this case, a biopsy of the pericardium – the lining around the heart – would be performed. While the test may sound frightening and can be uncomfortable, it takes just a few minutes and doctors will do everything possible to lessen any discomfort. Results of the biopsy can sometimes take more than a week, but will confirm or deny the diagnosis of mesothelioma.
After receiving a heart illness diagnosis, seeking a second opinion is often recommended due to their similarities to pericardial mesothelioma.
Treatment
If tests are positive for mesothelioma, patients will probably be given a choice of just a few treatment options given the fact that many traditional treatments can so easily damage the heart. Also, because the disease is usually diagnosed in its late stages, due to the fact that it can lay dormant for up to 40 or 50 years, options are less than for cancers that can be diagnosed early. Generally, the primary treatment options include:
- Surgery
- Palliative Care
- Chemotherapy
Surgery
Surgery is rarely recommended in the case of pericardial mesothelioma due to the location of the tumors. It may, however, be suggested for an appropriate candidate. If it is suggested, a pericardiectomy may be performed, where part or all of the affected pericardium is removed. This procedure can also reduce fluid buildup and pressure, helping the heart function more optimally.
Read more: Mesothelioma Surgery
Read more: Mesothelioma Surgery
Palliative Care
Because there is no cure for this or any type of mesothelioma, oncologists will usually suggest mesothelioma treatment options that relieve symptoms, reduce pain, or improve the overall quality of life for the patient. As part of a palliative treatment plan to help minimize discomfort and pain, procedures that remove excess fluid are often performed, including pericardiocentesis and fine needle aspiration. Removing the excess fluid aids in reducing pain and pressure around the heart.
Chemotherapy
Treatments traditionally used for the other forms of mesothelioma, including chemotherapy and radiation, have been less successful in treating pericardial mesothelioma. Patients will want to consider chemotherapy as an option carefully as it can greatly compromise one’s quality of life while providing little or no chance for a cure.
Prognosis
Doctors and research scientists are still searching for a way to cure mesothelioma or at least extend the life of those suffering from all types of the disease. Because it is almost always diagnosed in its late stages and due to limited treatment options, more than half of pericardial patients pass away within six months of a diagnosis.
Diagnostic aids that will result in earlier diagnosis of mesothelioma are currently being tested and other forms of treatment are being surveyed in clinical trials, all in hopes that the lives of mesothelioma patients can someday be prolonged.
Source:
- Warren WH: The clinical manifestations and diagnosis of mesothelioma. Mesothelioma: Diagnosis and Management. Edited by Kittle CF. Chicago: Year Book; 1987: 31.
- Pass HI: Emerging translational therapies for mesothelioma. Chest 1999, 116:455S-460S.
- Kralstein J: Malignant pericardial diseases: diagnosis and treatment. Am Heart J 1987, 113:785-790.
- https://www.maacenter.org/mesothelioma/types/pericardial-mesothelioma/
