A Rare Type of Cardiac Metastatic Mass

A 54-year-old female patient with a history of cancer that had been treated 5 years prior presented to the hospital with chest pain and shortness of breath. Bedside echocardiography showed a pericardial effusion requiring a pericardial window for drainage. Positron emission tomography (PET) computed tomography (CT) scan showed mediastinal lymphadenopathy, and a transthoracic echocardiogram (TTE) showed the following (Figure 1).

Figure 1

Figure 1

Which of the following is this mass least likely to represent?

Show Answer