放射線治療が奏効した再発を繰り返す後腹膜脂肪肉腫

A case of recurrent retroperitoneal liposarcoma successfully treated by radiotherapy

58歳，女性。近医にて右腎後方の後腹膜腫瘍に対し摘出術施行。病理組織診断は悪性線維性組織球症（MFH）であった。3年後，腹部CTにて再発を認めたため，当科を紹介され腫瘍と右腎摘出術を施行した。病理結果は脂肪肉腫であり，以前の病理をみかえすと脂肪肉腫と考えられた。1年後再発したため放射線治療を行った。治療に奏効し病巣は縮小，4年間増大傾向はなかった。しかし，その後再発したため放射線治療を追加し，現在外来通院中である。

In a 58-year-old female with retroperitoneal tumor located posterior to the left kidney,the tumor was surgically removed and the pathological diagnosis was MFH. Three years later local recurrence was detected with CT scan. And the patient was sent to our hospital for further treatment. We performed extirpation of the retroperitoneal tumor en block with right kidney. The pathological diagnosis was liposarcoma. And the postoperative course was uneventful. However,one year later the local recurrence was again detected which was treated by external beam irradiation. Remarkable regression of the tumor lesion was seen and there was no tumor regrowth after 4 years of follow up.