腎癌との鑑別が困難であった腎門部Schwannomaの1例

Abstract

58歳女.心窩部痛を主訴に受診した.血液生化学検査, 尿検査とも異常を認めなかった.腹部造影CT検査で, 左腎門部に突出し, 不均一な造影効果のある腫瘍を認めた.MRI検査で腫瘍は, T1強調画像で低信号, T2強調画像では高信号を呈し, 造影MRI検査で周囲に不均一な増強効果を認めた.腎細胞癌と診断し, 腹腔鏡下根治的腎摘除術を施行した.HE染色で紡錘型の細胞の増殖が認められ, Schwannomaと診断したが, 核異型, クロマチン濃縮, 核分裂像などの悪性所見は認められなかった.術後経過は良好で再発を認めない

A 58-year-old female presented with a well-encapsulated tumor in the left renal hilum on computed tomography (CT). On magnetic resonance imaging (MRI), the tumor showed low intensity on the T1-weighted image, high intensity on the T2-weighted image. Laparoscopic radical nephrectomy was performed because we could not exclude the possibility of malignancy such as renal cell carcinoma. Histopathological examination revealed that the tumor was a benign Schwannoma. Although renal hilum is a common site of renal schwannoma, it is difficult to differentiate benign tumors from malignant ones, and then nephrectomy is usually performed.