CT in malignant cardiac tumors (diagnosis, approach, follow-up)

Key points

• Cardiac CT has several advantages including wide availability, rapid acquisition time, excellent isotropic spatial resolution, and multiplanar reconstruction capabilities.

• CT is a robust technique for assessment of the relationship of the mass to the myocardium, cardiac valves, pericardium, coronary arteries, great vessels including pulmonary and systemic, and adjacent tissues, such as lung and lymph nodes, in a way that no other imaging modality can often reach.

• Metastasis to the heart is more common than a primary malignant tumor.

• Metastasis may involve the heart and pericardium by one of four pathways: retrograde lymphatic extension, hematogenous spread, direct contiguous extension, or transvenous extension. The predominant route is a retrograde lymphatic extension.

• The most common primary malignant cardiac mass is sarcoma and angiosarcoma is the most common.

• The right atrium is the most common cardiac chamber involved by a primary malignant tumor.

CT has emerged as an important imaging modality in the evaluation of cardiac and paracardiac masses. CT has several advantages including wide availability and rapid acquisition time, excellent isotropic spatial resolution, and multiplanar reconstruction capabilities. CT demonstrates excellent, three-dimensional rendering of the masses, which is essential for surgical planning. The wide field of view of CT enables visualization of paracardiac and other extracardiac structures, which is essential for staging malignancies.

Malignant masses are often more challenging to specifically diagnose, but the differential diagnosis can often be narrowed, and more importantly, the examination may document the extent of the lesion and presence or absence of additional (extracardiac) metastatic lesions, perform preoperative coronary evaluation, and be used to help plan biopsy or resection.

Cardiac computed tomography (CT) is particularly helpful in establishing the presence of thrombus versus enhancing tissue, and the pattern of enhancement in perfused masses may lead to insights that a mass is hypervascular, has a dominant fibrous component, or demonstrates features typical of a vascular malformation.

Newer techniques, such as CT perfusion and dual energy CT, may be useful in characterizing tissue and enhancement characteristics .

Tissue characterization

Metastases to the heart and pericardium are much more common than primary cardiac tumors and are generally associated with a poor prognosis. A primary malignant tumor is less common than a primary benign tumor, with most of them being sarcomas. Imaging features of tumors in CT that help distinguish benign from malignant neoplasms include location, size, margins, the presence of a feeding artery, calcification, or pericardial effusion ( Table 12.1 ) .

Technical issues

See Chapter 11 .

Primary malignant cardiac tumors