During a decade (1975-1985) 15 patients have been treated for a primary cardiac tumor at the University Hospital of Ghent. Histological examination revealed both benign (n = 12) (myxoma, pseudomyxoma, myxoid degeneration) and malignant (n = 3) (angiosarcoma) tumors. Tumor diagnosis generally was made by echocardiographic and/or angiocardiographic examination of patients presenting with various constitutional and/or cardiac symptoms. In two patients however diagnosis became obvious by histological examination of the material removed during acute embolectomy. All tumors were surgically resected with the aid of extracorporeal circulation. Benign tumors have generally good prognoses, although rhythm or conduction disturbances, complete obstruction or embolization can entertain malignant consequences. Three of our patients died of such a complication. Therefore all cardiac tumors should be resected as soon as possible after diagnosis. One patient showed evidence of recurrence of the tumor. Malignant heart tumors have bad prognoses: all three of our patients died within two years.