The mysterious pathways of cardiac myxomas: a review of histogenesis, pathogenesis and pathology

Cardiac myxoma is the most common benign cardiac tumour, localized generally in the left atrium. The majority of cardiac myxomas occur sporadically, while a relatively small proportion of cases develop as a part of Carney complex syndrome. Currently, the histogenesis of myxoma is poorly understood; however, the mesenchymal and endothelial properties of myxoma cells suggest that a clearer understanding of tumour origins can be achieved through a detailed investigation of heart development and endocardial histogenesis. Growing evidence appears to indicate the reactivated expression in cardiac myxoma of genes encoding heart precursor markers, although the exact mechanisms have not yet been described. In this paper we review the most recent scientific literature concerning cardiac embryology and relate this to recent advances in our understanding of the histogenesis of cardiac myxoma. Moreover, given that much of the literature regarding myxoma is of single case reports, we review progress in our knowledge of the pathology and pathogenesis of this condition.