Pericardial mesothelioma is a very rare form of mesothelioma that develops in the pericardium — the thin membrane surrounding the heart. It accounts for only about 1% or less of all mesothelioma cases, making it far less common than the pleural (lung lining) and peritoneal (abdominal lining) forms.

Cause

Like other forms of mesothelioma, it is linked to asbestos exposure, though because of its rarity the pathway by which fibers reach the pericardium is less fully understood than for pleural disease. As with all mesothelioma, it develops decades after exposure.

Symptoms

Because the tumor surrounds the heart, symptoms often relate to heart and circulatory function and can be mistaken for other cardiac conditions:

  • Chest pain
  • Shortness of breath, including when lying down
  • Irregular heartbeat or palpitations
  • Fluid buildup around the heart (pericardial effusion)
  • Fatigue and difficulty breathing on exertion

What Treatment Looks Like

Because of where it sits, the options are narrower than for pleural or peritoneal disease. Complete surgical removal is rarely achievable — the tumour encases a structure that cannot be resected. Pericardiocentesis drains fluid to relieve pressure; a pericardial window creates a drainage route to stop it reaccumulating; pericardiectomy removes part of the sac in selected cases.

Systemic chemotherapy is used as it is in pleural disease, and immunotherapy has been applied by extension from the pleural evidence rather than from trials specific to this form — there are too few cases to have run them. Treatment is accordingly individualised to a degree unusual even in rare cancers, and a second opinion from a mesothelioma programme is worth more here than almost anywhere.

Why It Is So Often Found Late

Pericardial mesothelioma is the rarest form, accounting for a very small fraction of an already rare cancer. That rarity shapes everything about it: few clinicians have seen a case, the symptoms point first at far more common cardiac disease, and a meaningful share of cases have historically been identified only at autopsy.

The presenting problem is usually fluid or thickening around the heart restricting how well it can fill and pump. Pericardial effusion causes breathlessness and chest discomfort; at its most acute it produces cardiac tamponade, where accumulating fluid compresses the heart and requires urgent drainage. Constrictive pericarditis — a stiffened, thickened sac — produces similar limitation more gradually.

The practical consequence is that an asbestos-exposure history is disproportionately valuable here. It is often the only thing that moves mesothelioma onto a differential otherwise occupied by heart failure and viral pericarditis.

Diagnosis & Treatment

Pericardial mesothelioma is especially difficult to diagnose because of its rarity and its location; it is sometimes found during treatment for another heart condition or only through biopsy. Imaging (echocardiogram, CT, MRI) and tissue sampling are used to confirm it. Because of where it grows, treatment options can be limited, and care is highly individualized — often focused on relieving pressure on the heart and managing symptoms, sometimes with chemotherapy. Care at an experienced mesothelioma center is especially important for this rare form.

If you or a loved one was diagnosed with pericardial mesothelioma and were exposed to asbestos at work, in the military, or in a building, you may have a legal claim.

This information is educational, drawn from sources such as the American Cancer Society and National Cancer Institute, and is not medical advice. Consult your own physicians about diagnosis and treatment.