SIGNET-RING STROMAL TUMOR OF THE OVARY - A HISTOCHEMICAL, IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL-STUDY

We report a signet-ring stromal tumour found in the ovary of a 50-year -old woman. The solid tumour was composed of spindle and round cells w hich stained with vimentin and some round cells were vacuolated and ha d the appearance of signet-ring cells. The vacuoles were negative with periodic acid-Schiff, with and without diastase digestion, with alcia n blue, Sudan III, alpha-1-antitrypsin and alpha-fetoprotein stains. U ltrastructurally, they were membrane bound and contained scanty floccu lent material. Some neoplastic cells contained intracytoplasmic eosino philic globules which were positive with alpha-1-antitrypsin. Signet-r ing stromal tumour is a benign, morphologically distinctive type of ov arian stromal tumour, which may present problems in differential diagn osis with other stromal and non stromal ovarian neoplasms.