Primary cardiac undifferentiated sarcoma: role of intraoperative imprint cytology and frozen section of two cases.

Primary cardiac tumors are very rare, and a vast majority of such malignant tumors are sarcomas. Associated symptoms are usually vague and nonspecific resulting in a late diagnosis and poorer prognosis. Most cardiac sarcomas have been reported in autopsy series. Although echocardiography may help make a diagnosis of a cardiac sarcoma, histopathological confirmation is quintessential. Presented here are two cases of patients who underwent successful surgery for the removal of a cardiac tumor, along with echocardiographic, cytological, and histopathological findings as well as a compact literature review. In both patients, the masses were on the surface of the mitral valve, and intraoperative evaluation of frozen sections and imprint cytology were indicative of a "probably malignant" mesenchymal tumor prompting more extensive surgical resection. Immunohistochemical staining of the resected material in both cases was only positive for vimentin, leading to a diagnosis of undifferentiated sarcoma. One of the patients died 3 months after surgery, while the other who received adjuvant chemotherapy was still alive after 4 months. Surgery remains the most definite treatment for cardiac sarcomas. The use of intraoperative frozen section and imprint cytology plays an important role in the decision to extend surgical resection.