Multimodality Imaging of an Oligometastatic Cardiac Angiosarcoma (QF_TH_045)

Description of Clinical Presentation: A 23-year old woman, otherwise healthy, initially presented with presyncope over the last few years. This worsened approximately six months prior to hospital visit. There was no family history of cancer. The patient was tachycardic (heart rate in 110s beats per minute), but normotensive (blood pressure 120 to 130 systolic, over 100 diastolic) with pulse pressure variation. An emergent bedside echocardiogram (TTE) showed a large circumferential pericardial effusion (figure 1) with a large mass encasing the right atrium. Due to impending tamponade, pericardiocentesis was then performed. Cytology showed reactive mesothelial cells but not evidence of malignancy. A subsequent cardiac MRI/MRA (figure 2) was performed to better characterize the mass. This confirmed a large heterogenous mass with invasion of the right atrium, pericardium, right pulmonary artery, and tricuspid valve. The cross-sectional imaging also showed late gadolinium enhancement (LGE) of the mass with dark focal central areas representing likely necrosis. The patient received a surgical incision biopsy and subxiphoid pericardial window; pathology revealed tumor cells (positive for CD31, CD34, ERG, SMA, negative for desmin, HHV8); these immunohistologic findings combined with morphologic features were consistent with poorly-differentiated cardiac angiosarcoma. An FDG-PET/CT (figure 3) was performed confirming the site of the cardiac tumor, avid area in the subpectoral and axillary lymph nodes, and an area of linear sclerosis in the femur. Biopsy revealed the same immunohistological chemistry and metastatic disease. She ultimately received chemotherapy with adriamycin, ifosfamide, and mesna.


Diagnostic Techniques and Their Most Important Findings: Mutlimodality imaging is crucial, even before biopsy of a cardiac mass. Prompt echocardiography (figure 1) was paramount to the initial diagnosis and treatment (pericardial tamponade, right atrial mass). This gave a sense of impacted cardiac structures and chambers, but the cardiac MRI (figure 2) added more value to defining the tumor. MRI defined the tissue planes and involvement of pericardium, pulmonary artery, right coronary artery, and the size of tumor necrosis. This was instrumental to decisions to expedite a surgical biopsy (not taken lightly given the invasiveness of a xiphoid incision and pericardial window). PET fusion and CT imaging (figure 3) for staging and surveillance allowed for metastatic characterization and ultimately timely inpatient chemotherapy.

Learning Points from this Case: Primary cardiac angiosarcoma is exceedingly rare but unfortunately when found is often at an aggressive state. Multimodality imaging, specifically with cardiac MRI and its role in tissue characterizations (T1, first-pass perfusion, early and LGE), serve to define tumor anatomy as well as to locate metastases. In this case, the patient presented with chronic lightheadedness and presyncopal symptoms, which was a harbinger for the tumor's likely infiltration and compression of structures such as the vena cava, pulmonary arteries, and right heart sided outflow. Using non-invasive diagnostic testing (echocardiography, MRI, and then FDG-PET) were integral to deciphering the ultimate malignancy and accelerate the process of treatment.