What is Pericardial Mesothelioma?

The Pericardium: Understanding the Affected Area

The pericardium is a double-layered sac that encases the heart, providing it with lubrication and protection from friction as it beats. The pericardium consists of:

• Visceral Layer: The inner layer, which is in direct contact with the heart.
• Parietal Layer: The outer layer, which forms a tough, protective barrier.

Between these two layers is a small amount of fluid that helps reduce friction between the heart and surrounding tissues during heartbeats. Pericardial mesothelioma occurs when cancerous cells develop in this lining, often causing thickening of the pericardium and fluid buildup, which can interfere with heart function.

Causes of Pericardial Mesothelioma

Like other types of mesothelioma, pericardial mesothelioma is primarily linked to asbestos exposure. However, due to the rarity of the condition, the exact mechanisms by which asbestos fibers reach the pericardium are not well understood.

Asbestos Exposure

• Inhalation and Migration: It is believed that asbestos fibers may be inhaled and travel through the bloodstream or lymphatic system, eventually lodging in the pericardium. Over time, these fibers cause inflammation and cellular damage, leading to cancer development. Learn more about how asbestos exposure leads to mesothelioma.
• Other Potential Causes: While asbestos exposure is the primary known risk factor, the low number of cases makes it difficult to fully understand all potential causes. Some researchers have hypothesized that genetic factors or previous radiation therapy to the chest could also contribute to the development of pericardial mesothelioma.

Symptoms of Pericardial Mesothelioma

The symptoms of pericardial mesothelioma are often vague and can be easily mistaken for other heart-related conditions, which complicates early diagnosis. As the disease progresses, symptoms typically become more severe.

Common symptoms include:

• Chest Pain: Persistent or severe pain in the chest, often similar to the pain experienced during a heart attack.
• Pericardial Effusion: Buildup of fluid in the pericardium, leading to increased pressure on the heart and difficulty breathing.
• Heart Palpitations: Irregular or rapid heartbeat caused by the pressure on the heart from the thickened pericardium or fluid buildup.
• Shortness of Breath: Difficulty breathing, especially when lying down, due to the reduced ability of the heart to pump effectively. This can be a common symptom in various types of mesothelioma, including pleural mesothelioma.
• Fatigue: Generalized weakness and tiredness, which can be debilitating.
• Cough: A persistent cough, often caused by the pressure of the fluid buildup on the lungs.

Due to the non-specific nature of these symptoms, pericardial mesothelioma is often misdiagnosed as other cardiovascular conditions such as pericarditis, heart failure, or coronary artery disease.

Diagnosis of Pericardial Mesothelioma

Diagnosing pericardial mesothelioma is particularly challenging because of its rarity and the overlap of its symptoms with those of more common heart conditions. The diagnostic process typically involves multiple steps:

Imaging Tests

• Echocardiogram: An ultrasound of the heart that can detect pericardial effusion and thickening of the pericardium.
• CT Scan or MRI: These imaging tests provide detailed images of the chest and can help identify masses or fluid buildup in the pericardium.
• PET Scan: May be used to detect areas of high metabolic activity, which can indicate the presence of cancer.

Pericardiocentesis

• Fluid Analysis: In cases of pericardial effusion, a needle may be used to remove fluid from the pericardium for analysis. This fluid can be examined for the presence of cancerous cells, though this test alone is often not definitive.

Biopsy

• Pericardial Biopsy: A tissue sample may be taken from the pericardium, usually during a surgical procedure, to confirm the presence of mesothelioma. This is the most definitive way to diagnose pericardial mesothelioma.

Blood Tests

• Biomarkers: Certain blood tests may show elevated levels of specific biomarkers, such as mesothelin, which can support a diagnosis of mesothelioma, although they are not conclusive on their own. For more information on this, see diagnosing mesothelioma.

Treatment Options for Pericardial Mesothelioma

Given the rarity and complexity of pericardial mesothelioma, treatment options are limited and often focused on managing symptoms and improving quality of life. The choice of treatment depends on the stage of the disease, the patient’s overall health, and the specific characteristics of the cancer.

Surgery

• Pericardiectomy: A surgical procedure that involves removing part or all of the pericardium to relieve pressure on the heart and improve symptoms. This procedure may be palliative, aimed at reducing symptoms rather than curing the disease.
• Tumor Resection: In some cases, surgeons may attempt to remove localized tumors, though this is often difficult due to the proximity to the heart and other vital structures.

Chemotherapy

• Systemic Chemotherapy: The use of drugs to target and kill cancer cells throughout the body. Chemotherapy may be used to slow the progression of the disease and manage symptoms, though its effectiveness in treating pericardial mesothelioma is limited. For more on this, read about how chemotherapy works for mesothelioma.

Radiation Therapy

• Targeted Radiation: Radiation therapy may be used to shrink tumors and relieve symptoms. However, the use of radiation near the heart must be carefully managed to avoid damaging healthy heart tissue.

Palliative Care

• Symptom Management: For patients with advanced disease, palliative care focuses on relieving symptoms such as chest pain and shortness of breath, and improving quality of life. This may include the drainage of pericardial effusion, pain management, and supportive care.

Prognosis and Survival Rates

The prognosis for pericardial mesothelioma is generally poor due to the aggressive nature of the disease and its close proximity to the heart. Most patients are diagnosed at an advanced stage, and the median survival time is often less than a year from diagnosis. However, outcomes can vary depending on the stage of the disease, the patient’s overall health, and response to treatment. Early detection and aggressive treatment can sometimes extend survival and improve quality of life.

Conclusion

Pericardial mesothelioma is a rare and challenging form of cancer that affects the lining of the heart. Due to its rarity and the non-specific nature of its symptoms, it is often difficult to diagnose and treat effectively. However, understanding the disease, its causes, and the available treatment options is crucial for those affected by pericardial mesothelioma and their healthcare providers. Ongoing research and clinical trials continue to seek better ways to diagnose and treat this challenging condition.

Sources:

• National Cancer Institute - Pericardial Mesothelioma Overview
• American Cancer Society - Detailed Guide on Pericardial Mesothelioma
• Centers for Disease Control and Prevention (CDC) - Asbestos and Mesothelioma
• Mayo Clinic - Pericardial Mesothelioma Symptoms and Treatment