抗CD20モノクローナル抗体の単独投与が有効であった全周性狭窄型十二指腸原発follicular lymphomaの1例

Primary Follicular Lymphoma of the Duodenum with Stricture, Effectively Treated by Rituximab, Report of a Case

要旨　患者は，60歳，男性．主訴は腹部膨満感，嘔吐．内視鏡およびX線所見で，十二指腸第2部に全周性狭窄を認めたが，確定診断は困難であった．術中所見では，悪性所見は乏しかったが，術中生検の病理学的検索で悪性リンパ腫（follicular type）と診断した．バイパス術後約1年後に再来院し，全身検索を行ったが，臨床病期は，stage Iだった．治療として，抗CD20モノクローナル抗体（以下，rituximab）とCHOP療法の併用を考えたが，患者の希望でrituximabの単独投与を施行．計8回の投与で，腫瘍は縮小し，臨床的にはPRと判断した．十二指腸の悪性リンパ腫（follicular type）は比較的まれで，明確な治療基準はない．今回の症例は，腫瘤形成し，十二指腸に狭窄を来した進展例にrituximabの単独療法を施行し，PRではあるが，効果を認めた．同疾患の治療に関して，示唆に富む症例と考え，報告する．

　A 60-year-old male was admitted to our hospital complaining of vomiting and a feeling of abdominal fullness. Duodenal stenosis was pointed out by the endoscopy and X-ray examination, but definite diagnosis was not obtained. Thereafter, bypass surgery and surgical biopsy was performed. Histologic and immuno-histochemical examination of the specimen revealed a follicular lymphoma, grade 2. After one year, the patient was readmitted for further treatment. Re-examination revealed that the tumor size had not enlarged and the clinical stage had not advanced. As treatment for this tumor, Rituximab administration had been selected and the tumor regressed successfully. Stricturing type follicular lymphoma is rarely reported and reports of the medical treatment are few. Rituximab might be a new medical therapy.