胃Leiomyoblastomaの1例

A CASE OF LEIOMYOBLASTOMA OF THE STOMACH

1．はじめに

　下腹部不快感，呑酸，そう囃を主訴として来院し，胃レ線検査，胃内視鏡検査で，胃粘膜下腫瘍と診断し，手術の結果Stout¹⁾の提唱したLeiomyoblastomaであった1例を報告する．本例は腫瘍の大部分は典型的なLeiomyoblastomaの像を示し，ごく一部にLeiomyomaと考えられる部分があり，両者間に移行像がうかがわれる症例である．

　This is a case report of leiomyoblastoma of the stomach designated by Stout, detected in the pyloric antrum of a 56-year-old female. The patient came to the hospital because of unpleasant sensation in the lower abdomen and heart burn. At x-ray study of the stomach, an oval shadow defect with smooth surface accompanied with bridging folds was found in the pyloric antrum. On palpation, it felt resistent as of a tumor against the palpating hand. Endoscopically a hemispheric tumor with bridging folds in its margins was recognized on the posterior wall near the greater curvature of the antrum. The surface of the tumor was smooth, covered by the same kind of the mucosa as of the surrounding area. As a submucosal tumor, in all probability leiomyoma, was suspected by both x-ray and endoscopic examinations, gastrectomy was performed. In the resected stomach, a gourd-like tumor, measuring 3.6×2.2×2.1 cm, developed in the muscularis mucosae and demarcated against the neighboring areas by a thin membrane as of connective tissue, was found in the pyloric antrum near the greater curvature. It had elastic soft consistency and its cut surface of yellowish white color, was pultaceous. Histopathologically most of the tumor tissues consisted of those cells either with their cell bodies becoming pellucid like vacuoles or forming lacunules or otherwise having lacunules around the cell bodies themselves, presenting a typical histological features of leiomyoblastoma (Stout). A part of the tumor tissues consisted of spindle-shaped cells in close-packed arrangement as is usual in leiomyoma.

　A greater part of the tumor described here corresponds to what Stout in 1962 designated as leiomyoblastoma, with the rest belonging to leiomyoma. As there seems to be a transitional zone between these tumor types, this case has been here presented with some reference to the literature.