Intraoperative cytologic diagnosis of unsuspected cardiac myxoma: a case report

Atrial myxoma is the most common primary intracardiac tumor. The diagnosis is generally primary intracardiac tumor, based on classical clinical findings coupled with echocardiographic or magnetic resonance image findings demonstrating a cardiac mass.

Unsuspected atrial myxoma was found in a woman who had been diagnosed with invasive lobular carcinoma of the breast. The echocardiographic findings in the presence of fever favored a clinical working diagnosis of infective endocarditis complicating a suspected cardiac metastasis. While intraoperative frozen section examination could not rule out metastatic invasive lobular carcinoma, cytologic touch imprint findings were diagnostic of myxoma. This appears to be the first report of concurrent breast carcinoma and atrial myxoma. To our knowledge, this is also the first report of intraoperative cytologic diagnosis of cardiac myxoma.

In myxoma cases with a complicated clinical setting in which frozen section examination may be equivocal, intraoperative cytologic examination may be a useful diagnostic tool.