[Clinicopathologic study of cardiac myxofibrosarcomas]

Objective: To investigate the clinicopathologic features of cardiac myxofibrosarcomas. Methods: The clinical data, pathomorphologic and immunohistochemical features were evaluated in five cases of cardiac myxofibrosarcoma collected from January 2009 to December 2014, with relevant literature review. Results: Five patients with cardiac myxofibrosarcoma, including four women and one man [age range 39-61 years; mean (50.4±9.0) years] were included. All tumors were broadbased and located mainly in the left atrium, with one case extending through the atrial wall and pericardium to the left lower lung lobe. The morphological grade was low in one case, intermediate in one, and high in three. Using Fédération Nationale des Centres de Lutte Contre le Cancer (FNLCC) grading system, one case was grade 1 and four cases were grade 2. Immunohistochemical analysis revealed diffuse and strong expression for vimentin in all cases. Smooth muscle actin and muscle specific actin were variably expressed. Complete tumor excision was performed in one case, and tumor debulking was performed in the other four cases. Clinical follow-up was available in three cases. One patient with en bloc excision of the tumor mass survived 13 months and the other two with tumor debulking died one month after surgery. Conclusions: The most common location for cardiac myxofibrosarcoma is the left atrium. Some myxofibrosarcoma may be histologically bland and misdiagnosed as myxoma due to histological similarities. Thus caution should be exercised in their microscopic differentiation. Precise imaging, multidisciplinary approach and adequate initial surgery may contribute to improving the clinical outcomes of myxofibrosarcoma.