腹壁Desmoid Tumorの1例

DESMOID TUMOR OF THE ABDOMINAL WALL

I．はじめに

　Desmoid tumor （類腱腫）は1832年Macfar—leneにより初めて報告され，1838年Müllerにより，本腫瘍が密な腱様の硬度を有するところから，desmoidと名づけられた。

　欧米においては，既に多数例による検討もなされているが，本邦での報告は非常に少なく，従つて本腫瘍についての組織学的検索も不充分のようである。

The reported cases of desmoid tumor in Japan are rare. Its histologic characteristics are degeneration and atrophy of muscular tissue within a fibrous tumor. As a pathogenesis of this tumor trauma theory of overstretching of the abdominal wall by pregnancy is the most probable.

A case of this tumor in the abdominal rectus muscle in a 42-year-old woman who had 2 pregnancies was reported. Histologic picture was complicated and showed fibromatous, myxo-matous hyalinosis and invasion of the tumor into the fat tissue. There was no severe necrosis and inflammatory infiltration was slight. Moderate chronic inflammatory infiltrates were found in the peripheral areas of invasion and mast cells were disseminated throughout the tumor or aggregated around the vessels. There was some atypicality of the tumor cells but no mitotic figure. The fibrous tissue showed strong positive reaction by PAS stain, but almost negative in metachromasia by toluidine-blue stain. Fibers which stain red by van Gieson's stain, blue by azan stain, and brown by argyrophilic stain, were running irregularly in form of bundles, nets or waves. There were no elastic fibers in the center of the tumor, but debris of the de-generated fibers could be seen in some peripheral regions.