Pericardial Mesothelioma

Pericardial mesothelioma is a primary tumour arising from the mesothelial lining of the serosal pericardium. It is exceptionally rare, and its rarity—not a distinctive symptom—often delays recognition. The 2021 WHO classification groups pleural and pericardial mesothelial tumours together and recognizes epithelioid, biphasic, and sarcomatoid subtypes. Current terminology is pericardial mesothelioma or diffuse mesothelioma; the older prefix “malignant” is no longer required for localized or diffuse disease. The tumour may form a localized mass, but diffuse involvement is clinically more typical and more difficult to treat. Tumour spread thickens and stiffens the pericardium, interferes with ventricular relaxation, and promotes recurrent or loculated effusion. The result may be: - Tamponade: fluid pressure outside the heart impairs filling. - Constrictive pericarditis: a rigid, scarred or tumour-infiltrated pericardium limits diastolic expansion. - Effusive-constrictive physiology: fluid causes tamponade while the diseased pericardium continues to restrict filling after drainage. These mechanisms can coexist. A patient may therefore have both a large effusion and signs of chronic right-sided heart failure. A history of asbestos exposure supports the occupational history but does not establish or exclude this diagnosis....