Purpose: This study was performed to identify morphologic features of cardiac myxomas related to embolism and to provide a better understanding of the biology of these tumors, mainly in relation to their interleukin (IL)-6 expression and DNA content.
Patients and methods: A total of 37 cardiac myxomas were reviewed retrospectively in a clinicopathologic study that included the correlation of echocardiographic and pathologic findings in 25 cases, together with immunohistochemical evaluation of IL-6 expression and flow cytometric DNA analysis of 35 tumors.
Results: There were 24 female patients and 13 male patients. The mean (+/- SD) age was 52 +/- 15 years. Fifty-four percent of patients presented with dyspnea, 51% presented with increased erythrocyte sedimentation rate (ESR), and 27% presented with embolic episodes, which were significantly associated with villous surface tumors. Atrial fibrillation was registered in 19% of patients and was significantly associated with large left atrial myxomas. Echocardiography proved to be a reliable method for preoperative diagnosis and for predicting tumor size and morphology. There was no perioperative mortality or long-term recurrences. The frequency of early surgical complications was associated with a longer mean ischemic time. Seventeen percent of tumors had abnormal DNA content, and 74% of tumors showed immunohistochemical expression of IL-6. Neither of these factors showed a significant association with embolism or constitutional illness.
Conclusions: Villous surface myxomas are related to embolism, and large left atrial tumors are related to atrial fibrillation. Echocardiography is a reliable method with which to predict tumor size and morphology. Myxoma cells usually express IL-6, and some tumors have abnormal cellular DNA content. Surgical excision of the tumor is a safe and effective treatment.