腎被膜より発生した悪性線維性組織球腫の1例

Abstract

43歳女.右下腹部痛を主訴に近医受診し, 超音波検査で右後腹膜腫瘍を指摘され, 精査加療目的で入院となった.入院後の画像検査所見でも右後腹膜腫瘍と診断され, 経腹的腫瘍切除術を施行した.腫瘍は右腎を合併切除する形で完全切除することが可能であった.病理組織学的に腎被膜由来の悪性線維性組織球腫と診断した.術後一過性の脳虚血発作を発症したが保存的に軽快し退院となった.補助療法は施行せず外来経過観察となったが, 術後2年7ヵ月経過現在再発は認めていない

We report a case of malignant fibrous histiocytoma originating in a renal capsule. A 43-year-old woman was admitted with a chief complaint of right lower abdominal pain. Physical examination was unremarkable. Serum C-reactive protein and erythrocyte sedimentation rate increased to 3.8 mg/dl and 60 mm/hr., respectively. Computed tomography (CT) and magnetic resonance image (MRI) showed a heterogeneous enhanced mass, 4 x 9 x 13 cm in size, in contact with the lateral part of the right kidney. Selective right renal arteriography revealed a hypovascular tumor, the main feeding artery of which was the right adrenal artery. Preoperative clinical diagnosis was a retroperitoneal sarcoma and transabdominal tumor resection was performed. The adhesion between the tumor and the right kidney was so severe that right nephrectomy was also necessary for a radical surgery. The tumor, measuring 13 x 9 x 6 cm, was located laterally adhering to the right renal capsule. Microscopic examination of the tumor demonstrated spindle-shaped fibroblast-like cells arranged in a storiform pattern with fibrous stroma and clusters of rounded histiocyte-like cells and pleomorphic giant cells with bizarre nuclei. Histopathological diagnosis was malignant fibrous histiocytoma arising from the renal capsule and there was no tumor invasion to renal parenchyma. No adjuvant therapy was performed but she has remained well for 31 months since the operation without evidence of disease.