除菌療法無効でrituximab併用THP-COP療法が奏効した巨大皺襞型胃MALTリンパ腫の1例

Response of MALT Lymphoma of the Giant Rugal Type in the Stomach to Rituximab＋THP-COP Combination Therapy After Failure of Bacterial Eradication Therapy, Report of a Case

要旨　70歳代，女性．2006年4月中旬に，吐血を主訴に当院受診．上部消化管内視鏡検査にて，胃噴門部から胃体下部にかけて小彎を主体とした著明な皺襞腫大と，粘膜面からの自然出血を認め，生検病理組織所見より，胃MALTリンパ腫と診断された．身体所見にて左鎖骨上窩に径1.5cm大の腫瘤を触知し，胸部CTにて両側肺野に小結節影を認め，臨床病期はstage IV（Lugano国際分類）と判定した．巨大皺襞型で，H. pylori陰性例であり，除菌治療抵抗性と予測されたが，二次治療を念頭に置いた相対的適応として，まず除菌を行った．除菌後，貧血の進行を認め，早急に二次療法（rituximab併用THP-COP療法）を施行した．同化学療法6クール施行後の治療効果判定で，臨床的にも病理組織学的にも胃病変は消失した．なお，肺病変，左鎖骨上窩の腫瘤は治療経過中変化がなかった．治療後8か月経過した現在も寛解を維持している．

　A woman in the 8th decade of life was examined in our hospital in mid-April, 2006 for the chief complaint of vomiting blood. Upper GI endoscopy revealed marked rugal enlargement extending from the cardia to the distal portion of the body of the stomach, primarily on the lesser curvature, and spontaneous bleeding from the mucosa. A diagnosis of gastric MALT lymphoma was made on the basis of the histopathological findings in a biopsy specimen. On physical examination a 1.5 cm mass was palpated in the left supraclavicular fossa, and CT of the chest revealed small nodular shadows in both lung fields. The clinical stage was concluded to be stage IV (Lugano International Classification). Since it was the giant rugal type and was H. pylori-negative, it was predicted that it would be resistant to bacterial eradication therapy, but as a relative indication bacterial eradication was performed first. The progression of anemia was observed after the bacterial eradication, and secondary therapy (rituximab＋THP-COP) was applied immediately. The efficacy of treatment was evaluated after carrying out 6 courses of the same regimen, and the gastric lesion was found to have resolved both clinically and histopathologically. There were still no changes in the pulmonary lesions or the mass in the left supraclavicular fossa. The remission has been sustained so far, 8 months after treatment.