2年間経過観察した早期胃悪性リンパ腫の1例

Early Gastric Lymphosarcoma, Report of a Case: Follow up study with x-ray, gastroendoscope and gastric biopsy during the past two years

　胃悪性リンパ腫は病理組織学的にReactive Lymphoreticular Hyperplasia（RLH），ときに未分化癌との鑑別が難しく，術前診断の困難な例も報告されている．われわれは初回の胃生検にてRLHと診断し，以後定期的な経過観察を続け，約2年後最終的に早期胃悪性リンパ腫（リンパ肉腫）と診断した1例を経験したので報告する．

　A 45 years-old woman visited Saiseikai-Kumamoto-Hospital owing to a complaint of epigastralgia. Abnormal clinical findings could not be recognized, but by initial x-ray examination of the stomach, a Ⅱc-like lesion with fold convergence was seen on the anterior wall side of greater curvature at the angle. However, biopsy revealed no malignancy, and diffuse invasion of lymphocytes with follicular structures was seen. Initial gastric biopsy showed no malignant lymphoma, so we started long follow up for two years under a diagnosis of reactive lymphoreticular hyperplasia (RLH). X-ray and endoscopic examination were performed every three months.

　A number of gastric biopsy materials was diagnosed as RLH at the initial gastric biopsy, but two years later a new irregular depressed lesion was seen on the posterior wall of the middle body.

　As biopsy of this lesion was highly suggestive of malignant lymphoma, operation was performed.

　On the resected specimen, a depressed lesion measuring 2.2×1.8 cm with fold convergence and a discolored lesion measuring 4.3×3.5 cm were seen. Histologically two lesions were separated from each other, and infiltration of lymphosarcoma cells was both limited within the mucosa and submucosa without metastasis to the regional lymphnodes.

　It may be called “multiple early lymphosarcoma” if the definition of early gastric cancer be adopted. Although there are several reports about differential difficulty between RLH and malignant lymphoma histologically, our present case seemed to be a most remarkable one.