What Is the Difference Between Primary and Secondary Cardiac Neoplasms?
Primary cardiac neoplasms originate within the heart, whereas secondary cardiac neoplasms are tumors that spread to different body parts from the primary tumor. Primary cardiac neoplasms can either be benign (non-cancerous) or malignant (cancerous), whereas secondary cardiac neoplasms always develop from the primary malignant cardiac neoplasms.
Secondary cardiac neoplasms constitute nearly 95 percent of all cardiac tumors, whereas primary cardiac neoplasms constitute five percent of all cardiac tumors.
What Are the Different Types of Primary Cardiac Neoplasms?
The primary cardiac neoplasm is categorized into two types:
1. Benign Primary Cardiac Neoplasms:
The benign primary cardiac neoplasms constitute 80 percent of all primary cardiac neoplasms. It is more commonly seen in young children but also affects adults. The most common benign primary cardiac neoplasms include:
Myxoma:
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Myxoma is the most common primary cardiac neoplasm that arises exclusively in the cardiac endocardium (the innermost tissue layer of the heart).
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Myxoma most commonly affects elderly patients aged between 30 to 60. A slight female predominance is seen in myxoma.
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The exact cause of myxoma is unknown. But some studies suggest that genetic predisposition could be an underlying cause of myxoma; such myxomas are called familial myxoma.
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It is mainly found in the left atrium (upper heart chamber). The other common sites of myxoma in the heart include the right atrium and ventricles (the two large lower chambers of the heart).
Papillary Fibroelastoma:
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Papillary fibroelastoma is a rare benign primary cardiac neoplasm. It represents around 75 percent of all cardiac valvular tumors (tumors that arise in the heart's valves).
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It mainly affects the mitral or the aortic valve but also the tricuspid and pulmonary valves.
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Elderly patients are most commonly affected by papillary fibroelastoma.
Lipoma:
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Lipoma is a type of primary cardiac tumor that is characterized by the presence of benign fatty cells.
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It most commonly occurs in the subendocardial region (the region that lies deep to the endocardium), and the other common sites include the myocardial (the muscular layer of the heart) and subepicardial regions (the region that lies deep to the epicardium).
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Lipomas are most commonly observed in elderly and obese male patients.
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It is mostly asymptomatic, but when the size of the lipoma increases, it causes symptoms like arrhythmias (irregular heartbeat), dyspnea (shortness of breath), chest pain, conduction block, and even sudden death.
Rhabdomyoma:
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Rhabdomyoma is a rare primary cardiac neoplasm closely associated with tuberous sclerosis (a multisystem genetic disorder that causes benign tumor growths on the skin and other organs).
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It is the most common primary cardiac neoplasm in children.
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Children affected with rhabdomyoma can also have tuberous sclerosis.
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Angiolipomas in the kidney (a benign tumor growth made up of blood vessels and fat).
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Astrocytoma (a tumor that occurs in the brain or spinal cord).
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Angiofibromas of the skin (a benign tumor made up of fibrous connective tissue and blood vessels).
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It tends to appear with multiple tumor growths inside the heart either in utero or within one year after their birth. The tumor growth generally resolves on its own after birth.
Fibroma:
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Fibroma is a benign tumor characterized by the neoplastic proliferation of fibroblasts.
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It is the second most common tumor of the heart in children.
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Fibromas are intramural tumors in which calcification is more common. Radiographically it appears as a firm, white bulging mass with clearly demarcated borders.
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Cardiac arrhythmia is one of the most common symptoms of cardiac fibroma.
2. Malignant Primary Cardiac Neoplasm:
Malignant primary cardiac neoplasms are relatively rare tumors that constitute 20 percent of all primary cardiac tumors. It mainly affects adults between the ages of 30 to 50. Malignant primary cardiac neoplasms include different types of sarcoma, such as,
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Angiosarcoma: A type of cancer that forms in the blood and lymph vessels lining.
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Rhabdomyosarcoma: Cancer arising from mesenchymal cells, which give rise to rhabdomyoblasts.
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Leiomyosarcoma: A rare malignant tumor that arises in the smooth muscle tissue.
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Liposarcoma: A malignant tumor of fatty tissue most commonly seen in adulthood.
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Fibrosarcoma: A rare type of malignant cardiac tumor that comprises fibrocytes and is characterized by extensive areas of hemorrhage and necrosis.
The sarcomas tend to proliferate rapidly and cause widespread infiltration of the myocardium, obstructing the blood flow through the heart and leading to death. The malignant primary cardiac neoplasms often exhibit a poor prognosis, with median survival ranging between six to twelve months.
What Are the Symptoms of Primary Cardiac Neoplasms?
The symptoms of primary cardiac neoplasms depend on two main factors, the size and location of the tumor and whether it is benign or malignant.
The most common symptoms of primary cardiac neoplasms include;
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Chest pain.
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Arrhythmia.
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Fatigue.
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Dyspnea.
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Slurred speech.
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Coughing up blood.
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Conduction disturbances in the heart.
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Blood flow obstruction in the heart.
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Pericardial Effusion: Fluid accumulation in the pericardium (a fibrous membrane that surrounds the heart and heart vessels).
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Heart failure.
How Are Primary Cardiac Neoplasms Diagnosed?
The diagnosis of primary cardiac neoplasms mainly relies on the use of different imaging techniques. The various imaging techniques used for diagnosing primary cardiac neoplasms include;
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CT (Computed Tomography) Scan: CT scan is one of the most commonly used diagnostic tools in detecting cardiac tumors. It helps detect the size, location, and extent of the tumor. In addition, the presence of calcifications or fat deposits in cardiac tumors is well visualized through CT scan imaging; thus, it helps in the differential diagnosis of cardiac neoplasms.
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Cardiovascular MRI (Magnetic Resonance Imaging): Cardiovascular magnetic resonance imaging uses a powerful magnetic field and radio waves to give detailed images of the structures within the heart. It helps assess cardiac tumor characteristics by providing detailed images of the tumor and its surrounding tissues. A cardiovascular MRI is a superior diagnostic tool to a CT scan since it offers high contrast and detailed heart images.
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Echocardiography: Echocardiography is a diagnostic test that provides live images of the heart using ultrasound waves. It uses no radiation; therefore, it is safer than a CT scan. It also helps in detecting the tumor site, location, and extent. In addition, it is valuable in determining whether the cardiac tumor is benign or malignant by assessing the different characteristics of the tumor.
Some of the significant advantages of echocardiography over other imaging techniques used in diagnosing cardiac neoplasms are that it is less expensive, portable, readily available, non-invasive, and real-time imaging.
How Are Primary Cardiac Neoplasms Treated?
Surgical tumor resection is the ideal treatment for benign and malignant primary cardiac neoplasms. Surgical resection can be difficult in some instances where the tumors lie deep inside the heart structures. However, it helps improve the outcomes and increases the overall survival of patients.
Surgical resection and chemotherapy (treatment that uses drugs to kill cancer cells) help improve the outcomes and overall survival rate in malignant primary cardiac neoplasms.
Conclusion:
The prognosis of primary cardiac neoplasm varies with the benign and malignant variants of primary cardiac neoplasms. Malignant primary cardiac neoplasms often exhibit a poorer prognosis than benign primary cardiac neoplasms, with a median survival time ranging from six to twelve months. The overall survival rate of patients may increase after surgical resection of primary cardiac neoplasms.
