Unlike pleural mesothelioma that is strongly associated with asbestos exposure, the causes of pericardial mesothelioma are uncertain. Treatment options may include surgery for cancers that have not spread, chemotherapy, or clinical trials.
Basics
Mesothelioma is a tumor that arises in tissues called mesothelium, and may occur in four primary regions of the body:
Pleural mesothelioma is a tumor of the lining of the lungs (the pleura) and accounts for 65% to 70% of these cancers. Peritoneal mesothelioma is a cancer of the membranes lining the abdomen (the peritoneum) and makes up 30% of mesotheliomas. Testicular mesothelioma is a cancer of the lining of the testicles (the tunica vaginalis) and makes up less than 1% of mesotheliomas. Pericardial mesothelioma is responsible for 1% to 2% of mesotheliomas.
While pericardial mesothelioma is similar to other forms of mesothelioma in some ways, there appear to be important differences as well. The median age of diagnosis is age 55, though the cancer can be found at any age.
Case reports of people as young as age 19 and 28 are found in the literature. The cancer occurs more often in men, but women represent a higher proportion of cases than is seen with pleural mesothelioma.
Symptoms of Pericardial Mesothelioma
The signs of pericardial mesothelioma are usually nonspecific, with the most common being chest pain and shortness of breath.
Other symptoms may include swelling of the legs (edema), palpitations, unintentional weight loss, and fatigue.
The symptoms are more easily understood by picturing what is happening in the heart. As the tumor grows in the lining of the heart, it restricts that ability of the heart to fill fully and contract normally (constrictive pericarditis).
The presence of the tumor itself can lead to pain (especially chest pain with a deep breath), and the restriction of heart motion can lead to symptoms of heart failure, such as shortness of breath and leg swelling.
Causes
While pleural and peritoneal mesotheliomas are strongly associated with asbestos exposure, the link is weaker with pericardial mesothelioma. Though some associations have been noted, the cause of these tumors is usually unknown. This is particularly true when the tumors begin in young people. The disease does not appear to be associated with smoking.
Abnormal heart rhythms Cardiac tamponade Sudden death (usually due to an arrhythmia): The risk of sudden death is not an uncommon complication, and roughly 70% of pericardial mesotheliomas are only diagnosed after death during an autopsy.
Asbestos Exposure
While frequently attributed to asbestos exposure, results of recent investigations question the relationship of both pericardial and paratesticular mesotheliomas with asbestos, at least in the United States.
According to a 2017 study, a substantial number of pericardial mesotheliomas occur in people who have had no known asbestos exposure. In addition, in evaluating large groups of people who have had heavy asbestos exposure, no cases of pericardial mesothelioma were reported.
Another 2016 study looked at people with pericardial mesothelioma in different populations and compared them with people who were diagnosed with pleural mesothelioma. The assumption was that, if asbestos plays a role in the causation of pericardial mesothelioma as it does with pleural mesothelioma, the incidence of both diseases should be elevated in regions where asbestos exposure is higher. Unlike higher rates of pleural mesothelioma (twice as high) in regions such as San Francisco and Seattle, however, the incidence of pericardial mesothelioma was not increased in these areas.
Unlike these U.S. studies, however, an Italian study did find a significant association between asbestos exposure and pericardial mesothelioma. Of people diagnosed in the Lombardy region who were available for interview, five out of seven had experienced occupational exposure to asbestos.
Medical Radiation
Medical radiation to the chest for lymphoma or breast cancer has been associated with mesothelioma in general, but only a few reports suggesting an association with pericardial mesothelioma have been published.
When mesothelioma occurs after radiation therapy, there is usually a latency period of 15 years to 25 years.
Genetics
Research looking at the genetics of cancer is young, especially with regard to mesothelioma. That said, associations with some chromosomal anomalies have been seen, and there is some evidence that the disease may be associated with hereditary BRCA1 mutations in at least some cases.
Diagnosis
The diagnosis of pericardial mesothelioma can be very difficult, and it’s not uncommon for the diagnosis to be made “accidentally,” such as when a procedure is done to drain a pericardial effusion or during open heart surgery.
A combination of studies, such as computed tomography (CT), magnetic resonance imaging (MRI), and echocardiogram followed by biopsy, is often needed to make a definitive diagnosis.
Imaging Studies
A regular chest X-ray may lead to suspicion but is not very helpful in diagnosis. A chest CT or MRI can be very helpful, both to identify the tumor in the pericardium and to look for spread of the tumor to nearby structures. A PET scan may also be used as an added test.
Procedures
An echocardiogram is often done, though the accuracy alone is low unless combined with imaging studies.
When a pericardial effusion is seen (fluid between the two layers of pericardium), a pericardiocentesis is often done. A pericardiocentesis is a test in which a long, thin needle is inserted into the pericardial space to withdraw fluid. Fluid may be removed to improve symptoms from a large pericardial effusion and/or to obtain a sample to look for the presence of cancer cells.
Biopsy
A biopsy is usually needed to confirm a diagnosis, but can be challenging due to the location of the pericardium around the heart and near major blood vessels.
A needle biopsy is commonly done, though other approaches may be needed. Pericardioscopy is a minimally invasive procedure (similar to a laparascopy in the abdomen) that may be used to obtain a biopsy sample.
Even when a biopsy sample is obtained and viewed under the microscope, the diagnosis may be difficult, and special testing (immunohistochemical antibody testing) may be necessary to make the diagnosis.
Biomarkers and Molecular Testing
Since pericardial mesothelioma is so rare, less is known about biomarkers and molecular testing than with many other types of cancer, but some advances are being made. Currently, these tests may be used to follow treatment, but it’s hoped that further research will lead to a screening tool in the future.
EpithelioidSarcomatoid (the poorest prognosis)Mixed
Differential Diagnosis
There are a number of conditions that may resemble pericardial mesothelioma with regard to either symptoms or findings on diagnostic tests. Some of these include:
Constrictive pericarditisMetastases to the pericardium (for example, from lung cancer or breast cancer)Heart failureOther pericardial tumorsLupus serositis of the pericardium: More than one person with pericardial mesothelioma has been first (erroneously) diagnosed with lupus serositis.
Treatment
Much of what is known about treating pericardial mesothelioma stems from research on pleural mesothelioma, and there are currently no standard therapies.
Overall, surgery is the treatment of choice when the cancer is localized to the pericardium. Pericardial mesotheliomas can spread locally to involve the conduction system of the heart and major vessels, as well as distantly to the liver or lungs.
Surgery
Pericardiectomy, or surgery to remove the pericardium is ideal when the cancer is caught early. That said, when these cancers are diagnosed roughly 25% to 45% will have spread to the liver or lungs, and others may have spread locally near the heart so that surgery is not possible.
When surgery is done, adjuvant treatment with chemotherapy (chemotherapy after surgery to “clean up” any leftover cancer cells) and/or radiation is often considered.
Radiation
Radiation alone does not appear to make a difference in survival, but may help with pain management due to the tumor. It’s important to note that with cancers such as this, the importance of addressing pain can’t be overstated.
Chemotherapy
Chemotherapy using the medications Platinol (cisplatin) and Alimta (pemetrexed) has improved the length of survival for some people with pericardial mesothelioma, and in at least one case, has led to prolonged progression-free survival.
Clinical Trials
At the current time, there are relatively few approved options for treating pericardial mesothelioma, and many oncologists recommend looking into clinical trials.
Fortunately, there are several different types of treatment that are beings studied (though several of these are for mesothelioma in general, rather than specifically pericardial mesothelioma). Some examples include:
Prognosis
At the current time, the prognosis for pericardial mesothelioma remains poor. A 2019 report of 103 cases found that the overall median survival (the time after which 50% of people have died and 50% are still alive) was six months. For those who received chemotherapy, the median survival was 13 months.
The prognosis is better for those who have the epitheliod rather than mesotheliod subtype, and for people who have tumors that have not spread to the region around the heart (the mediastinum) or distant organs.
It is important to note that, while the prognosis of pericardial mesothelioma is poor, there are some long term survivors. For example, a case report details a 59-year-old patient who underwent surgery and chemotherapy and remained alive and without symptoms three years after surgery.
Coping
Being diagnosed with any cancer is challenging, but with a cancer that is both rare and has few approved treatments such as pericardial mesothelioma, it can be heartwrenching.
Without raising false hope it’s important to note that the treatments and survival rates for cancer in general are improving, and even with mesothelioma there are several clinical trials in progress looking for newer and better therapies.
It’s important to talk to your healthcare provider about the option of clinical trials. Clinical trials are changing relative to the approach in the past. Many of these newer drugs have been designed specifically to address specific pathways in the growth of cancer, and as such, may be more likely to have an impact on a cancer than drugs that were studied in the past.
You may also wish to consider a second opinion, preferably at one of the larger cancer centers that has healthcare providers who specialize in the treatment of mesothelioma.
A Word From Verywell
Pericardial mesothelioma is a very rare tumor with few treatment options. That said, just as advances have been made with several other similarly difficult to treat cancers, there is hope that newer approaches, such as immunotherapy, will lead to better options in the near future.
While this, and advocacy in general, is extremely important, efforts to figure out the causes and make a difference are probably not what your loved one needs from you at this time. Even if you are feeling driven to investigate what may have made your loved one ill, try to focus on simply loving her for now.
