十二指腸リンパ腫の臨床診断と治療

Malignant Lymphoma of the Duodenum

要旨　消化管原発濾胞性リンパ腫は，十二指腸下行部に集簇した白色顆粒状病変として偶然発見されることが多く，空腸や回腸にも病変が存在することが多い．治療は経過観察から積極的な化学療法まで意見が分かれるが，自験例ではリツキシマブを併用したCHOP療法を行って全例完全寛解した．十二指腸MALTリンパ腫は，自験例では胃MALTリンパ腫を伴った症例やセリアック病を合併した症例があり，内視鏡所見は“潰瘍型”と“隆起型（顆粒型）”に分類された．Helicobacter pylori（H. pylori）除菌療法は，有効例と無効例の両方の報告がある．自験例では診断時にはいずれもH. pylori感染を認めず，30Gy放射線療法（1例は化学療法を併用）を行って完全寛解した．Aggressive lymphomaのうち2例は十二指腸原発と考えられ，十二指腸下行部にほぼ全周性の潰瘍性病変を認めた．1例は化学療法の途中で閉塞を来し，残りの1例は化学療法でいったん寛解したものの，その後2度再発を来した．

　FL（follicular lymphomas）of the gastrointestinal（GI）tract are relatively rare, and most of them are diagnosed as clusters of whitish granular lesions in the second portion of the duodenum. However, involvement of the jejunum and/or the ileum is often recognized. Strategy of treatment for FL of the GI tract is controversial, and several opinions such as“watchful waiting”or chemotherapy have been put forward. MALT（Mucosa-associated lymphoid tissue）lymphomas of the duodenum are rare. Their endoscopic findings might be divided into“ulcer-like type”and“protruded type（or granular type）”. Effectiveness of eradication therapy against Helicobacter pylori for MALT lymphomas of the duodenum is controversial, but 30Gy radiation therapy was effective in our cases. Aggressive lymphomas of the duodenum are also rare. Two of our 5 patients were thought to have primary duodenal aggressive lymphoma, and in the remaining 3 patients involvement of lymphoma cells was recognized at other sites of the GI tract simultaneously. Endoscopy revealed large ulceration with narrowing of the lumen in the second portion of the duodenum in the two patients with primary duodenal lymphoma. Non-surgical therapy using chemotherapy and/or radiation therapy was effective in both patients. However, obstruction of the duodenum was recognized halfway through chemotherapy in one patient, and endoscopic balloon dilation therapy led to perforation of the duodenum. This complication required an urgent surgical operation. On the other hand, relapse of malignant lymphoma had been recognized twice after that in another patient with T-cell lymphoma.