尿管周囲原発悪性リンパ腫の1例

Abstract

53歳男.心窩部不快感で左腎盂腎杯の拡張を指摘された.腹部骨盤部CT scanで左外腸骨動脈内側に造影効果のある25×18mmの腫瘤を認め, 逆行性腎盂造影では左仙腸関節部での尿管狭窄を認めた.MRIでは腫瘤はT1強調像で低信号, T2強調像で軽度高信号, Gd-DTPAで造影効果を示した.尿管鏡では狭窄部粘膜は平滑整で, 尿管内には明らかな異常は認めなかった.後腹膜原発腫瘍を疑い, 手術を行った.腫瘤は弾性硬, 平滑で紡錘状に尿管を全周性に取り巻き, 左外腸骨静脈と癒着していたが, 周囲及び尿との剥離は比較的容易で, 尿管は温存し, 腫瘤のみを摘出した.病理組織所見で, リンパ球の濾胞状増生を認め, 濾胞内リンパ球はCD-10及びbcl-1免疫染色に陽性であった.術後の全身検索で残存病変は認めず, 悪性リンパ腫は緩解状態と診断した.追加治療は行わず, 経過観察中である

A 53-year-old man was admitted with epigastric discomfort. Excretory pyelography demonstrated left non visualizing kidney. Computed tomography showed the dilatation of left renal pelvis and a mass along with a left lower ureter. Retrograde pyelography showed the stenosis of left lower ureter. Urine cytologies from both voided and upper urinary tract showed class I. Ureteroscopy revealed the normal ureteral mucosa, suggesting extrinsic obstruction of the ureter. The operation was performed under the diagnosis of retropelvic tumor. The tumor could be easily resected from the left ureter. The pathological diagnosis was follicular lymphoma. There was no prolificative accumulation on Gallium scintigraphy after the operation. The tumor was considered to have originated from paraureteral tissue.