初回X線検査でⅡc型早期癌と診断された胃MALTリンパ腫の1例

MALT Lymphoma of the Stomach Preceded by the Diagnosis of Type-Ⅱc Early Cancer at the Initial X-Ray Diagnosis, Report of a Case

要旨　患者は62歳，女性．当センターの間接胃集検にて，胃角部前壁にひだの集中・中断と内部に顆粒状変化を伴った不整形の陥凹性病変を指摘され，未分化型早期癌の診断にて要精密検査となった．内視鏡検査および精密X線検査では，病変は白苔を伴った溝状のびらんと，それに囲まれた比較的均一な，丸味を帯びた顆粒状変化からなり，MALTリンパ腫と診断した．生検診断もMALT lymphoma，compatibleであり，遺伝子検索でも免疫グロブリン重鎖の遺伝子再構成が認められた．以上より，胃MALTリンパ腫と最終診断し，H. pyloriの除菌治療を行った．その結果内視鏡所見は軽快し，生検でMALTリンパ腫の組織所見は消失したため，現在経過観察中である．表層型胃悪性リンパ腫は，萎縮性胃炎から胃癌まで様々な疾患との鑑別が問題となり，初回検査時の臨床診断は約5割がⅡC病変，多発びらん・潰瘍，萎縮性胃炎などとなっており，臨床上つねに表層型悪性リンパ腫を念頭に置くことが重要である．

　A female, at the age of 62, underwent mass screening of the upper gastrointestinal tract and was noticed to have both convergency and interruption of folds and an irregularly-shaped depression with internal granules on the anterior wall of the angular part. She was followed up subsequently by detailed examination because of suspicion of poorly-differentiated cancer. Endoscopy and x-ray showed that the lesion was characterized by narrow ditch-shaped erosions accompanied by whitish coating and roundish evenly sized granules surrounded by the ditch-shaped erosions. This was clinically diagnosed as MALT (mucosa-associated lymphoid tissue) lymphoma. Biopsy diagnosis was also compatible with MALT lymphoma. Furthermore, gene reconstruction at the site of Ig (H) JH was present. Based on the above alterations, the lesion was finally diagnosed as MALT lymphoma of the stomach and eradication therapy against H. pylori was carried out. Endoscopic findings have improved, biopsy findings indicative of MALT lymphoma have disappeared, and observation is still being carried on now. In the differential diagnosis of superficial-type malignant lymphoma of the stomach, a variety of diseases can be specified from atrophic gastritis to advanced gastric cancer. Generally, clinical diagnoses at the initial examination vary (about 50%), between type-Ⅱc, multiple erosion/ulcer, atrophic gastritis, etc., so, in clinical practice, the possibility of the presence of MALT lymphoma should also be kept in mind.