Primary Malignant Pericardial Epithelioid Mesothelioma Presenting as Cardiac Tamponade: A Case Report With Multimodality Imaging and Radiologic-Pathologic Correlation

Our plain-English summary of Primary Malignant Pericardial Epithelioid Mesothelioma Presenting as Cardiac Tamponade: A Case Report With Multimodality Imaging and Radiologic-Pathologic Correlation, by S. Dhakal, P. Savoia, N. Yasmine, et al (Case Reports in Radiology, 2026).

The study

• Authors: S. Dhakal, P. Savoia, N. Yasmine, S. Mitra
• Journal: Case Reports in Radiology
• Published: 2026;2026:7217020
• Cited by: 1 article, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Primary malignant pericardial mesothelioma is an exceptionally rare and aggressive malignancy that frequently presents with nonspecific cardiopulmonary symptoms, recurrent pericardial effusion, constrictive physiology, or cardiac tamponade. Early diagnosis is challenging because an infiltrative pericardial tumor may remain occult on initial imaging studies performed for acute cardiopulmonary evaluation. A 67-year-old woman presented with chest discomfort and shortness of breath. CT pulmonary angiography and thoracic aortic computed tomography angiography (CTA) were performed to evaluate for pulmonary embolism and acute aortic pathology. The examinations were negative for pulmonary embolism and acute aortic abnormality; however, they revealed a large mildly hyperattenuating circumferential pericardial effusion measuring approximately 35 HU, concerning for complex mixed hemorrhagic and serous fluid with tamponade physiology. No discrete enhancing pericardial mass was confidently identified on the initial CTA examination. Transthoracic echocardiography confirmed a large pericardial effusion with tamponade physiology. Pericardiocentesis removed approximately 600 cc of fluid, with cytologic analysis nondiagnostic for malignant cells. The patient returned approximately 2 weeks later with progressive dyspnea. Cardiac MRI demonstrated an extensive heterogeneously enhancing infiltrative anterior pericardial mass extending toward the great vessels and left atrial region. FDG PET/CT showed an intensely FDG-avid infiltrative pericardial mass without distant metastatic disease or FDG-avid lymphadenopathy. Thoracoscopy and pericardial biopsy confirmed epithelioid mesothelioma. Immunohistochemistry revealed positivity for CK7, calretinin, CK5/6, and WT1 and negativity for claudin-4 and TTF-1. The patient was treated with carboplatin and pemetrexed, with planned radiation therapy. This case highlights that primary malignant pericardial mesothelioma may initially present as complex hemorrhagic pericardial effusion with tamponade physiology, with infiltrative tumor occult on nondedicated acute CTA examinations. Persistent or recurrent symptoms following drainage should prompt further evaluation with cardiac MRI and PET/CT for tissue characterization, staging, and biopsy planning.

Copyright © 2026 Saubhagya Dhakal et al. Case Reports in Radiology published by John Wiley & Sons Ltd.

In plain English

This case report described a 67-year-old woman with primary malignant pericardial mesothelioma, a cancer of the lining around the heart. She came to the emergency department with chest discomfort and shortness of breath. Her available clinical history did not reveal known asbestos exposure. CT scans done to look for a lung blood clot or an aortic problem showed neither. They did show a large fluid collection around the heart, with signs of tamponade (pressure on the heart), but no tumor mass was confidently seen. About 600 cc of fluid was drained, but testing of the fluid did not establish a diagnosis of cancer. About two weeks later she returned with worsening breathlessness. Cardiac MRI showed an extensive infiltrating mass in the front of the pericardium. A PET/CT scan showed the mass was highly active and showed no signs of spread to lymph nodes or distant sites. A biopsy confirmed epithelioid mesothelioma. She was treated with carboplatin and pemetrexed chemotherapy, with radiation planned. The authors concluded that emergency CT scans may miss such tumors and that persistent symptoms after drainage should prompt cardiac MRI.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case report (single patient)
• Who was studied: one 67-year-old woman who presented to an emergency department with chest discomfort and progressive shortness of breath; no known history of prior malignancy
• Exposure: No asbestos exposure was identified: the available clinical history did not reveal known asbestos exposure, asbestosis, or other significant occupational or environmental exposure risk factors
• Main results:
  • Initial CT pulmonary angiography and thoracic aortic CTA were negative for pulmonary embolism and acute aortic abnormality but showed a large circumferential pericardial effusion measuring approximately 35 HU, compatible with complex mixed hemorrhagic and serous fluid
  • No pericardial mass was confidently identified on the initial CTA examination
  • Pericardiocentesis removed approximately 600 cc of fluid; cytologic analysis of the fluid was nondiagnostic for malignant cells
  • When the patient returned about 2 weeks later with progressive dyspnea, cardiac MRI showed an extensive heterogeneously enhancing infiltrative anterior pericardial mass extending toward the great vessels and left atrial region
  • FDG PET/CT showed intensely FDG-avid infiltrative pericardial soft tissue with a left pleural effusion, without FDG-avid lymphadenopathy or distant metastatic disease
  • Thoracoscopy and pericardial mass biopsy revealed epithelioid mesothelioma; immunohistochemistry was positive for CK7, calretinin, CK5/6 and WT1 and negative for claudin-4 and TTF-1
  • The patient was treated with carboplatin and pemetrexed, with planned radiation therapy
• The authors' conclusion: The authors concluded that primary malignant pericardial epithelioid mesothelioma should be considered in patients with complex hemorrhagic pericardial effusion and tamponade. In their view, acute CTA done for pulmonary embolism or aortic evaluation may fail to identify the tumor, persistent or recurrent symptoms after drainage should prompt dedicated cardiac MRI, FDG PET/CT assists with staging, and definitive diagnosis requires histopathology with immunohistochemistry.

Topics

Medical terms in this study, explained in our Lexicon: Pericardial, Epithelioid, Mesothelioma, Cardiac Tamponade, Pericardial Mesothelioma, Pericardial Effusion, Pathology, Serous Fluid.

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