Primary Left Atrial Osteosarcoma

Abstract

SummaryPrimary cardiac osteosarcomas are rare entities, mostly arising from the left atrium. Because of their rarity, few reports have described this uncommon lesion. We herein report a case of primary cardiac osteosarcoma originating from the left atrium in a 34-year-old woman, who underwent tumor debulking surgery and died 3 months after being diagnosed.(Int Heart J 2017; 58: 1024-1027) Key words: Left atrium, Cardiac tumor P rimary cardiac tumors are extremely rare with a prevalence ranging from 0.001% to 0.030% in autopsy series.1) The majority of cardiac tumors are metastatic, accounting for 20-40 times more cases than primary tumors.2) Only approximately 25% of primary cardiac tumors are malignant, and less than 10% of primary cardiac malignant tumors are osteosarcoma.3,4) Primary cardiac osteosarcomas, as one subtype of sarcomas, are much rarer than other primary sarcomas, such as angiosarcoma, leiomyosarcoma, and undifferentiated sarcoma. 5)As far as it is known, there have been fewer than 40 cases reported over the last 40 years from the first case described by McConnel et al. in 1970. 6,7) Case ReportA 34-year-old woman was admitted to our department presenting with a 3-month history of progressive dyspnea and frequent expectoration. At the onset of dyspnea and expectoration episodes, she visited a regional hospital but simply received symptomatic treatment. Nevertheless, her symptoms were not alleviated. On admission, a transthoracic echocardiogram revealed a well-defined mass (57 × 32 × 28 mm) with a broad base attached to the lateral wall of the left atrium and very close to the left atrial appendage ( Figure 1A-C). Transesophageal echocardiogram detected the mass, the tip of which prolapsed into the left ventricle at the mitral valve level, causing a mild functional mitral valve stenosis ( Figure 1D). Threedimensional echocardiogram reconstructed the spatial geometric shape of the mass. It was uneven and nonlobulated, suspended from the free wall of the left atrium ( Figure 1E, F). Without further assessment of morphology, in combination with our prior experience, we diagnosed this mass as a cardiac myxoma, which in hindsight was a rushed conclusion, and therefore a surgical resection was scheduled.After induction of anesthesia, median sternotomy, cardiopulmonary bypass, and aortic and bicaval cannulation, as a set of routine procedures, were performed. Intraoperatively, the findings were beyond our expectations. The mass was not shaped like a cardiac myxoma but looked more like "fish-flesh" matter. The patient underwent a tumor debulking surgery other than complete resection due to the finding that the tumor had invaded into the ventricle, which made complete resection impossible.The tumor was detached into pieces with sharp and blunt dissection and removed from the atrium. These pieces had a smooth and irregular surface, an elastic and firm consistency, and a tannish-yellow color. Scattered hemorrhagic foci were seen in the cut sections (Supplemental Figure A).Histopathology with hematoxylin-e...

A Primary Cardiac Osteosarcoma: Case Report and Literature Review

“…Primary cardiac tumors are rare, with a prevalence of autopsy being reported to be 0.001-0.030% [2]. Among all the primary tumors, the malignant one's account for about 25% [4]. About 95% of primary cardiac malignancies are sarcomas and osteosarcomas, and the latter accounts for less than 10% [5].…”