術前に確定診断された胃のbizarre leiomyoblastomaの1例

A Case of Bizarre Leiomyoblastoma Preoperatively Diagnosed by Biopsy

　近年胃のX線および内視鏡診断技術の進歩に伴い，胃粘膜下腫瘍の発見ならびに質的診断も向上し，その報告例が数多く見られるようになった．bizarre leiomyoblastomaも術後の病理学的検索によって発見された症例は幾らか報告が見られるが，術前に質的確定診断のなされた報告はまだ見られない．われわれは最近本症を経験したので報告する．

　A 44-year-old male began to have hunger epigastralgia in May 1973 and was hospitalized 1 week later for minute examination.

　Double contrast image in supine position revealed a well-defined elevated lesion with a central niche in the posterior wall of gastric body. A few bridging folds were noted. With gastrofiberscopy, the lesion was found to be covered by the smooth mucosa having usual color. The base of ulcer demonstrated some hemorrhagic foci and a relatively small amount of necrotic material covering. Two biopsy materials obtained from the margin of ulcer showed neoplastic tissue. The tumor cells were arranged densely and solidly without alveolar structure. The majority of tumor cells were spherically swollen by vacuolar degeneration. Special stainings for glycogen, mucus and fat revealed negative results. Some tumor cells were spindle in shape, representing smooth-muscle character. From these findings, the lesion was diagnosed as bizarre leiomyoblastoma. From Stout's criteria, the lesion was regarded to be benign, because mitosis was scarcely seen.

　Gastrectomy was carried out on May 31, 1973. The tumor was located mainly in the submucosa and partly in the proper muscle coat and considered to have arisen from the proper muscle coat.