Cardiac myxoma the great imitators: Comprehensive histopathological and molecular approach

Cardiac myxomas are rare benign and slowly proliferating neoplasms of uncertain histogenesis with heterogeneous histomorphology and variable and sometimes clinically quite malignant pathological manifestations. Majority of cardiac myxoma occur sporadically while a relatively small proportion of diagnosed cases develop as a part of Carney complex syndrome with established familial pattern of inheritance. Although histologically indistinguishable these two forms of cardiac myxoma exhibit distinct cytogenetic make-up and apparent pathological differences important for their clinical presentation and prognosis. Additional problem is presented with secondary lesions with more aggressive histology and significantly faster cell proliferation suggesting their successive malignant alteration. Surgical resection of cardiac myxoma is currently the only treatment of choice. However, to avoid potentially hazardous operating procedures and possible postoperative complications and to prevent recurrence of the neoplastic lesions it is necessary to develop alternative approaches and identify a possible drug targets for their successful pharmacological treatment. Due to the rarity of the disease, a small number of cases in one institution and lack of comprehensive experimental data particularly concerning the cases of metastatic dissemination and secondary lesions with malignant nature, a comprehensive multi-institutional approach is required for better understanding of their molecular pathology and illumination of key molecular, genetic as well as epigenetic markers and regulatory pathways responsible for their development. In this article we provide comprehensive pathohistological, molecular and cytogenetic overview of sporadic cardiac myxoma cases restating the major hypothesis concerning their histogenesis and emphasizing potential approaches for their further reexamination.