Most heart tumors begin with myxomas, fibromas, rhabdomyomas, and hamartomas, although malignant sarcomas (such as angiosarcoma or cardiac sarcoma) have been known to occur. In a study of 12,487 autopsies performed in Hong Kong seven cardiac tumors were found, most of which were benign. According to Mayo Clinic: "At Mayo Clinic, on average only one case of heart cancer is seen each year." In a study conducted in the Hospital of the Medical University of Vienna 113 primary cardiac tumour cases were identified in a time period of 15 years with 11 being malignant. The mean survival in the latter group of patients was found to be 26.2 ± 9.8 months.
Primary malignant cardiac tumors (PMCTs) are even more rare. A study using the Surveillance, Epidemiology and End-Results (SEER) Cancer Registry from 1973-2011 found 551 case of PMCTs, with an incidence of 34 cases per million persons. The study also found that the incidence has doubled over the past 4 decades. The associated mortality was very high, with only 46% of patients are alive by 1 year. Sarcomas and Mesotheliomas had the worst survival, while lymphomas had better survival. When compared with extracardiac tumors, PMCTs had worse survival.