Although still rare, most cancers found in the heart, having come from elsewhere in the body, are composed of white blood cells. Most heart tumors are not cancerous (benign)
Heart cancer (primarily heart tumors) is cancer that arises in the heart. Cancerous (malignant) tumors that start in the heart are most often sarcomas, a type of cancer that originates in the body's soft tissues. Most heart tumors are not cancerous (benign).
Heart cancer is very rare. For example, a review of more than 12,000 autopsies identified only seven cases of heart tumors - an incidence of less than 0.1%. At one major US medical center, an average of only one case of heart cancer is seen each year.
Although still rare, most cancers found in the heart have come from elsewhere in the body. These include lymphatic cells that originate in the chest near the heart. Other cancers that can spread to the heart include melanoma and sarcomas.
Heart cancer can cause the following:
Obstruction of blood flow through the heart.
Increased stiffness of the heart muscle (cardiac fibrosis).
The intervention of the heart valves (marantic endocarditis).
In the case of marantic endocarditis, the heart valves are damaged by cancer, and it can cause valve malfunctions. In severe cases, the heart valves may need to be replaced. Unfortunately, this is often a sign of very advanced cancer and carries a poor prognosis. A rare type of cancer called a carcinoid tumor at times produces hormones that can damage heart valves.
Cancer treatments can also affect the heart. Certain chemotherapy drugs - such as anthracyclines, high-dose cyclophosphamide (Cytoxan), fluorouracil (5-FU), taxanes, trastuzumab (Herceptxin), and interleukin-2 (IL-2) - can cause damage to the heart. Radiation therapy to or near the heart can also cause damage to the heart muscle and increase the risk of coronary artery disease later in life.