大腸ポリポーシスの形態を呈したadult T-cell leukemia（ATL）の1例

Adult T-cell Leukemia with Polyposis of the Colon, Report of a Case

要旨　患者は44歳，女性．発熱，倦怠感，下痢の精査治療目的で入院．両側鎖骨上窩，左鼠径部にリンパ節を触知し，CTでは両側腋窩リンパ節腫大と脾腫を認めた．末梢血では白血球数および分画中の異常リンパ球高値を認め，ATLA陽性，HTLV-Iプロウイルスが検出された．消化管では胃，小腸，大腸に病変がみられ，特に大腸ではポリポーシスの形態を呈していた．大腸からの生検組織でATL細胞の浸潤が確認され，広範に消化管浸潤を伴ったATLと診断し，化学療法を施行したところ，症状は改善し消化管の病変も消褪した．以上，大腸にポリポーシスの形態を呈する浸潤を認めたATLの1例を報告し，ATLの大腸病変の画像所見について文献的考察を加えた．

　A 44-year-old woman was admitted to our hospital complaining of fever, general fatigue, and diarrhea. She had swollen bilateral supraclavicular and left inguinal lymph nodes. White blood-cell count was increased and differential count showed 64% of the lymphocytes were abnormal, having large and cleaved nuculei. Anti-HTLV-I-antibody was positive and HTLV-I-proviral DNA was detected. Radiologic and endoscopic examinations revealed numerous polypoid lesions with central depression in all sites of the large intestine, small ulcers in the stomach, and edematous mucosal change in the jejunum. Histological examination of the biopsy specimen from colonic mucosa showed infiltration of abnormal lymphocytes with large and cleaved nuclei, which confirmed adult T-cell leukemia (ATL) involvement. After treatment by anti-cancer agents, most of the intestinal lesions disappeared. The polypoid lesions in the large intestine resembled so called multiple lymphomatous polyposis. Gastric and small intestinal lesions in this case were thought to be caused by infiltration of leukemic cells as well. Further discussion was held on radiologic and endoscopic features of large intestinal lesions in patients with ATL.