Ovarian sex cord tumor with annular tubules. Report of a case.

A 23-year-old woman underwent resection of a tumorous right ovary after long-standing irregular genital bleeding. The tumor measured 50 x 30 mm and had a yellowish-white solid cut surface with scattered small cysts. The light microscopic diagnosis was a sex cord tumor with annular tubules. Ultrastructurally, the tumor cells had Charcot-Boettcher filaments and showed vimentin positivity by immunohistochemistry. A three-dimensional reconstruction study proved that the tumor cell nests had a ovoid outer margin and contained blind-ended ellipsoid hyaline bodies. This tumor is presumed to be a variant of sex cord/stromal tumor showing differentiation predominantly to Sertoli cells.