胃良性リンパ腫の臨床診断―特に肉眼分類について

Clinical Diagnosis of Benign Lymphoma of the Stomach

　良性のリンパ細網系細胞の増生は，1928年Konjetzny¹⁾が“lymphatisch-hyperplastischer Gastritis”の名称で記載して以来，種々の変遷があったが，本邦では1966年に中村²⁾がreactive lymphoreticular hyperplasia（RLH）として6症例の報告を行って以後，この名称が一般的となっている．しかし，本疾患の悪性リンパ腫ならびに早期胃癌との臨床的鑑別が注目され，症例の報告が増加するに伴い，反応性増生のみならず，腫瘍性の性格をもったものあるいは良悪性境界領域病変の報告が散見されるようになった．それゆえに近年，潰瘍や慢性炎症による反応性のlymphoreticular hyperplasiaと良性リンパ腫を分けて考える学者も増加している．

　今回の特集に際し，反応性のlymphoreticular hyperplasiaと良性リンパ腫が臨床的に十分検討されていない現在，便宜的に両者を合わせて良性リンパ腫としてX線・内視鏡検査所見，切除胃肉眼所見を中心に検討を行った．

　Lymphoid hyperplasia of the stomach is commonly called as RLH in japan. On the other hand, recently so-called RLH tends to be classified into reactive lymphoreticular hyperplasia and benign lymphoma pathologically. In this series, however, reactive lymphoreticular hyperplasia and benign lymphoma were studied as benign lymphoma clinically.

　21 cases of resected benign lymphoma in our hospital were classified into following 5 types macroscopically.

　Ⅰ. Multiple Ulcero-erosive Type (12 cases)

　Multiple shallow depressions which show irregular stellate-like or topograph-like appearance cover a wide area. The surface of each depression is smooth. The mucosa surrounding each depression shows granular appearance, the granules are of various size and have smooth surface.

　Ⅱ. Depressed Early Cancer-like Type (6 cases)

　The form of this type resembles that of Ⅱc or Ⅱc+Ⅲ type of early cancer. Depression of the lesion is relatively flat and is accompanied by converging folds in almost all cases. Converging folds, sometimes, have characteristic abnormality such as smooth clubbing.

　Ⅲ. Saucer-like Ulcer Type (1 case)

　This type is difficult to be differentiated from saucerlike ulcer type of malignant lymphoma.

　Ⅳ. Submucosal Tumor Type (0 case)

　This type has not been experienced in our hospital. But a few cases have been reported. This is characterized by SMT-like elevation, many of this type have depressions at the tops of elevations.

　Ⅴ. Swelling Fold Type (2 cases)

　Swelling folds have smooth surface and no regidity. Many erosions or ulcers are present among the folds.