Mysterious Left Atrial Mass in a Patient With Metastatic Prostate Cancer

Cardiac tumors (CTs) are a rare group of disorders that encompass a broad set of masses. They are subclassified into neoplastic and non-neoplastic lesions. Neoplastic lesions can be further subdivided into either primary cardiac tumors (PCTs) or secondary cardiac tumors (SCTs) which are metastasis to the heart. Cardiac myxomas are the most common pathological type of benign PCT followed by rhabdomyomas, papillary fibroelastomas, fibromas, lipomas, and leiomyomas. Here, we present a case of a patient with left atrial mass in the setting of stage IV prostate cancer. We have used transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) for characterization and differential generation. Our findings are presented in high-quality imaging and video and our top differentials include PCT, thrombi, and metastasis. Although a full diagnostic workup was not completed due to limitations in diagnostic tests available, metastasis to the heart could not be excluded due to the high staging and extensive sclerotic involvement of this malignancy. We emphasized the importance of multimodality imaging, e.g., TTE, TEE, cardiac magnetic resonance (CMR), and cardiac computed tomography (CT) in the workup of incidental cardiac masses and differential refinement.