Primary sarcoma of the heart: a light and electron microscopic study of two cases

SUMMARY Two cases of primary malignant cardiac neoplasms are presented. The first, an angio-sarcoma of the right atrium, developed in a 44-year-old housewife, who survived 23 days from the time of presentation; diagnosis was made at necropsy. The second, an embryonal rhabdomyosarcoma of the right ventricle, developed in a 17-year-old student; diagnosis was made by angiocardiography. He underwent surgery and cytotoxic and irradiation therapy and died 14 months later. Primary malignant cardiac neoplasms are very rare; sarcomata form the vast majority. In classifying these tumours, the first step is to consider whether the tumour is of vascular or myogenic origin; in this paper we describe one example of each. The first, an angiosarcoma of the right atrium, presented little difficulty in histological classification at necropsy. Although the case had not been diagnosed during life, the symptoms were strikingly similar to those of previously recorded cases. In the second case,