Prevalence and pathology of primary cardiac tumors

Primary cardiac tumours are rare clinical observations, different from secondary neoplasms (ten times more frequent), and 90% of all primary cardiac tumours are benign. Myxoma is by far the most frequent benign tumour (75%), typically located in the left atrium, and manifests with intra-cavitary obstruction, embolism and constitutional symptoms, but it may also be silent and discovered incidentally by echo. Papillary fibroelastoma is a tumour usually arising on the valvular or mural endocardium, which, although quite small, may become symptomatic through embolic events. Typical tumours of the paediatric age group are fibroma, rhabdomyoma and teratoma. Primary malignant neoplasms account for 10% of all primary cardiac tumours and are represented by sarcomas (angiosarcoma, leiomyosarcoma, fibrosarcoma, liposarcoma, rhabdomyosarcoma undifferentiated pleomorphic sarcomas) and primary lymphomas. They usually infiltrate the cardiac walls, but may be also solely intra-cavitary, mimicking myxoma. Non neoplastic masses may consist of thrombi and infections, which again can be identified by a thorough surgical pathology examination. Cardiac non invasive imaging through transthoracic and transesophageal echocardiography easily detects heart masses. Cardiac magnetic resonance imaging and computed tomography are helpful complementary investigations, for refining diagnosis and in the post-surgery follow-up. Histology with immuno-histochemistry of any cardiac mass is mandatory for diagnosis, therapy and prognosis. Endomyocardial biopsy may be of help for histological investigation without thoracotomy particularly in right sided masses.