Pericardial Mesothelioma Presenting as Constrictive Pericarditis

Abstract

This case report presents a 60-year-old gentleman with a significant smoking history and possible asbestos exposure who was referred to the emergency department for atrial fibrillation with a rapid ventricular rate and symptoms of heart failure. Labs showed normal brain natriuretic peptide and troponin I. His echocardiography finding suggested constrictive pericarditis with an ejection fraction of 60%. A computed tomography scan was concerning for a pericardial mass. Left and right heart catheterization hinted more toward constrictive physiology; however, some findings were concerning for restrictive physiology. Hence, cardiac magnetic resonance imaging was done, which established the diagnosis of constrictive pericarditis. Pericardiectomy was planned with a maze procedure for atrial fibrillation. However, a malignant neoplasm was seen on a frozen biopsy. Hence, surgery was limited to partial pericardiectomy, as the patient had advanced infiltrative neoplasm that had resulted in constrictive pericarditis. The final pathology report confirmed the diagnosis of malignant pericardial mesothelioma mixed type. Malignancy is usually diagnosed in an advanced stage, like in our case, due to nonspecific initial presentation. A literature review suggests that there is a lack of established consensus on treatment. The response to therapy also seems to be poor and results only in palliation of symptoms, with a median survival of six months from diagnosis despite optimum medical management.

Keywords: constrictive pericarditis; constrictive physiology; pericardial mass; pericardial mesothelioma; pericardiectomy.

Figure 1. Electrocardiogram with blue arrows showing the fibrillary wave (see in atrial fibrillation) with a rapid ventricular rate of 108 beats per minute, with no significant ST-T wave changes

Figure 2. X-ray chest with red arrows in panels A and B showing large right pleural effusion with concerns for consolidation vs. atelectasis secondary to the effusion of the right lung base

Figure 3. Orange arrows in panels A and B pointing toward an anteroinferior pericardial mass, with concerns for neoplasm and a large right pleural effusion. Yellow arrows in Figures A and B showing right pleural effusion.

Figure 4. Red arrows in panels A, B, C, and D showing diffusely thickened, heterogeneously enhancing, and irregular pericardium measuring maximally 17.8 mm (in Figure B).

Figure 5. Epithelioid mesothelioma with pleomorphic cells and mitotic activity (hematoxylin-eosin, original magnification 400 X)

Pathology: Microscopic sections of the pericardial mass reveal epithelioid and sarcomatoid mesothelioma. A panel of immunoperoxidase stains shows positive staining for pan keratin, vimentin, CK7, and calretinin. The malignant cells show negative staining for LCA, SOX10, MART-1, WT1, CK20, monoclonal CEA, STAT6, TTF-1, and BerEP4. This immunoprofile is diagnostic of malignant mesothelioma. The tumor shows abundant mitotic activity, cellular pleomorphism, and tumor necrosis.