Clonal Origin Patterns Play a Vital Role in Cardiac Myxoma Recurrence.

OBJECTIVE

To explore the clonal origin pattern of cardiac myxoma and its relationship with recurrence of the disease.

METHODS

20 female patients diagnosed with cardiac myxoma underwent appropriate surgery and were followed-up after the treatment. The DNA of tumor tissues and pairing normal tissues from 20 patients were taken, with polymerase chain reaction (PCR) assay being used to amplify the HUMARA gene on X-chromosome, which could hint the tumor cloning state. Cases were divided into a polyclonal origin group and monoclonal origin group, according to the PCR result. The recurrence rate in the two groups was compared using Fisher's exact probability method.

RESULTS

All tumors were successfully removed. PCR assay showed that the hybrid rate in tumors was 90.0% (18/20). Among them, 88.9%(16/18) of cases were identified as polyclonal origin and 11.1%(2/18) were identified as monoclonal origin. After 4 years of follow-up, the recurrence rate was 12.5(2/16) in the polyclonal origin group and 0%(0/2) in monoclonal origin group, with significant difference between the two groups (<0.05).

CONCLUSION

Cardiac myxoma is mostly of polyclonal original, and its polyclonal origin characteristics may contribute to tumor recurrence.