Lymphoid hyperplasiaに合併せるⅡc型早期胃癌の1例

A CASE OF Ⅱc TYPE EARLY GASTRIC CANCER ACCOMPANIED WITH LYMPHOID HYPERPLASIA

Ⅰ．はじめに

　Ⅱc様所見を呈する広範な陥凹性病変と，粘膜下腫瘍を思わせる隆起性病変の共存した症例で，術前X線および内視鏡診断では，Ⅱc型早期胃癌の進行せるもの，または悪性リンパ腫あるいは良性の胃のReactive lymphoid hyperplasiaなどを考慮したが，確診は得られず，手術を施行した症例である．

　This is a report of a Ⅱc type early gastric cancer accompanied with lymphoid hyperplasia. A submucosal tumor, formed in the area of the latter by localized cancer infiltration, was very hard to be discriminated from such lesion as advanced carcinoma, submucosal tumor or malignant lymphoma.

　Case: a 54-year-old housewife. Chief complaint: pain in the upper abdomen. Six months previously a diagnosis of cholecystitis was made in an hospital, but as episodes of pain became frequent, she visited authors' hospital.

　X-ray examination: Mucosal convergence in a wide area around the gastric angle as well as knobby tips and discontinued ends of the rugae was suggestive of Ⅱc type depressed lesion. A shadow defect the size of a thumb-tip was also observed in the pyloric antrum, but its margins were not irregular. Tentative diagnosis was either Ⅱc type early gastric cancer with advanced carcinoma of protruded type or benign erosions with submucosal tumor.

　Endoscopy revealed a depression and discoloration in an extensive area encircling the gastric angle, accompanied with convergence and abrupt cessation of the mucosal folds. An irregular, protruded lesion was also noted on the posterior wall in the pyloric antrum. Early gastric cancer of Ⅱc+Ⅱa type was thus suspected.

　In the resected stomach a shallow, discolored depression was found around the incisura, measuring 4 by 6cm, extending down into the pyloric antrum. There was an ulcer scar in the center of the depression accompanied in its margins with convergence, enlargement, cessation and tapering-off of the mucosal folds. A tumor, measuring 2.4 by 2.1 cm, of relatively smooth surface, was also found on the posterior wall in the pyloric antrum.

　Concomitantly seven cholesterine gallstones were found in the gallbladder.

　Histophatologically, undifferentiated adenocarcinoma of signer ring cell type was found extending within the mucosal layer, corresponding in its extent to that of Ⅱc type depression which had an ulcer scar in its center. A part of cancer lesion had infiltrated into the submucosal layer in an area of Ul-Ⅱ.

　The tumor was formed by hyperplasia of lymphoid tissues in the submucosal layer, into which cancer infiltration as seen in the depressed lesion took place in an extensive degree. Malignant invasion, however, was localized within the lymphoid tissues. Muscle layer was free from it.