膵囊胞性疾患の内科的対応

Medical Management of Cystic Lesions of the Pancreas

要旨　膵囊胞の原疾患は多様である．治療を行う臨床的な立場からみれば，腫瘍に起因する囊胞か否かに分けて考えることが好都合である．診断においては囊胞性腫瘍の画像上の特徴を理解すると共に貯溜囊胞を随伴する膵癌や液化壊死を伴った腫瘍の診断に注意する必要がある．急性期膵仮性囊胞については，保存的療法や経皮的穿刺術を応用した内科的治療が良好な成績を得ている．現在までの成績から検討すると，径5cm未満のものでは保存的治療を4週間施行した後，改善傾向が乏しければ経皮的穿刺吸引法の適応となる．径5cm以上のものでは合併症発生の危険が高いので，積極的に経皮的穿刺吸引またはドレナージにて減圧術を実施することが必要であると言えた．これらの内科的方法で急性期膵仮性囊胞の約3/4を治療しえた．最近の画像診断の進歩に基づく，膵囊胞の診断と内科的治療，特に映像下穿刺による囊胞減圧術の有用性について述べた．

　Cysts of the pancreas are caused by various underlying diseases. From the viewpoint of clinical practice, it is required for us to differentiate the cysts by neoplastic tumors from the other ones. When diagnosing cystic lesions of the pancreas, we have to recall characteristic findings, including those provided by diagnostic imagings, of neoplastic cysts as well as of solid tumors associated with retention cysts or with intratumoral cysts resulting from liquefied necroses.

　There may be a number of acute inflammatory cysts of the pancreas which disappear spontaneously. Treatment modalities for these pancreatic cysts include an interventional method as well as surgery. Based on the results of treatment in 36 patients, we suggest therapeutic guidelines for the pancreatic cysts as follows; 1) conservative regimen may be allowed in expecting spontaneous resolution when the cysts are smaller than 5 cm in diameter, 2) interventional treatment such as percutaneous puncture aspiration or drainage is indicated for those larger than 5 cm in diameter because of high risk of complications and also for those which do not decrease in size in 4 weeks after a conservative regimen is applied. With these nonsurgical treatments, improvement was observed in approximately 3/4 of our patients with acute inflammatory cysts. In the paper, we emphasize the contribution of modern diagnostic imagings to the diagnosis and treatment of pancreatic cysts.