Heart cancer is extremely rare, with an incidence rate of less than one-tenth of 1 percent, according to the Mayo Clinic website. Over 70 percent of tumors that develop on the heart are benign, or noncancerous, reports New York-Presbyterian Hospital. The most common type of cancerous tumor of the heart is a cardiac sarcoma, which often develops on the right atrium and is known as an angiosarcoma. Other cancerous tumors of the heart include rhabdomyosarcoma, fibrosarcoma and liposarcoma. The exact causes of heart cancer are not well understood.
Other Cancers
Most cancers that develop in the heart are the result of metastasis of cancers in other parts of the body, the Mayo Clinic website explains. Lymphoma, which is cancer of the lymphatic system, is a common cause of heart cancer, especially when the lymphoma forms in a lymph node near the heart. Melanomas, a type of skin cancer, are another type of cancer that can easily spread to the heart. A third type of cancer that can spread to the heart is a sarcoma, which develops in connective tissue, the name given to tissues that surround and support organs in the body.
Radiotherapy
Heart cancer has been linked to radiation therapy administered to treat other forms of cancer, explains Cancer Research UK. The cells that line the walls of blood vessels and lymph ducts in the heart are more prone to developing cancerous tumors. Tumors that form in blood vessels are called haemangiosarcomas, and tumors that grow in lymph ducts are known as lymphangiosarcomas. Together, haemangiosarcomas and lymphangiosarcomas make up angiosarcomas, the most frequent type of cancerous heart tumor.
Cancer Risk Factors
The exact causes of cancer are not well understood by doctors, although several risk factors for heart cancer have been identified. Certain industrial chemicals, such as vinyl chloride, cadmium, nickel and benzene, have been linked to heart cancer, according to the Online Cancer Guide. Tobacco use also increases the risk of all types of cancer, including heart cancer. Heart cancer has a tendency to run in families, and a having close relatives with heart cancer means a person is at a greater risk of developing it. Infection with some viruses or bacteria can also increase the risk of heart cancer.
