JUVENILE GRANULOSA-CELL TUMOR DISCOVERED DURING PREGNANCY - CASE-REPORT WITH IMMUNOHISTOCHEMICAL STUDY OF STEROIDOGENESIS

A multilobular cystic juvenile granulosa cell tumor in a 33-year-old p regnant woman was examined. Pathological examination of the specimen a t Cesarian section at 38 weeks of gestation revealed three different h istological patterns; diffuse proliferation, trabecular or cord-like p roliferation, and characteristic microfollicular patterns, as well as the presence of numerous luteinized stromal cells. These histological patterns were intermingled and transference among these patterns was d etected. Immunoreactivity of steroidogenic enzymes including cholester ol side-chain cleavage, 3 beta-hydroxysteroid dehydrogenase and 17 alp ha-hydroxylase was detected only in luteinized stromal cells. However, that of adrenal 4 binding protein, a transcription factor of steroido genesis, was present in almost all the tumor cells as well as luteiniz ed stromal cells, suggesting th at tumor cells acquired the potential of metabolizing and synthesizing steroid hormones. The hormonal enviro nment associated with pregnancy altered the histological and biologica l features of this juvenile granulosa cell factor.