左房内平滑筋肉腫の1例

A case of left atrial leiomyosarcoma

　原発性心臓腫瘍は非常に稀であり，剖検頻度は0.0017〜0.28％であり，心膜または心臓への転移性腫瘍の剖検頻度は悪性病変をもった患者の1.5〜20.6％とされている^1〜4）。原発性心臓腫瘍の約80％は良性腫瘍で，粘液腫と横紋筋腫が多く，悪性腫瘍は残りの約20％でそのほとんどを肉腫が占め，血管肉腫，横紋筋肉腫，線維肉腫が多い。我々は原発部位を確定することはできなかったが，心臓原発と考えられる左房内平滑筋肉腫の1例を経験したので報告する。

Case report: A seventeen year old woman was admi-tted to Cerebral Surgery, Hamamatsu Rosai Hospital because of convulsion on July 10, 1985. A brain CT film showed a mass in the right fornix. She had two masses in her left leg. She had craniotomy for the brain tumor on August 6. She had precordial pain inmid-August. Chest X-ray film showed cardiomegaly. Two-dimensional echocardiography revealed a large left atrial mass. Therefore, she was transferred to our department on August 24. Two-dimensional echocar-diographic feature of the left atrial mass were 1) very slightly mobil mass 2) a size of 5×4 cm 3) the mass attached to the intraatrial septum with in an enlarged left atrial cavity. She died of heart failure on September 21. Histological diagnosis were leiomyosarcoma of the brain, the leg and the heart. Leiomyosarcoma of the heart is extremely rare, and two-dimensional echocar-diographic features were distinctly different from those of myxoma.