Sex cord-stromal tumors of the ovary

The developmental relationship between granulosa and stromal cells in the fetal ovary was reviewed. The proliferation and expression of basic fibroblast growth factor (bFGF) and luteinizing hormone receptor (LHR) of both the granulosa and theca cells was examined in the adult ovary. Ovarian granulosa cell tumors were then studied under light and electron microscopy and for immunohistochemical expression of bFGF and LHR. In the follicular development of the adult ovary, bFGF expression in the granulosa cells was correlated with theca cell proliferation. In ovarian granulosa cell tumors, estrogen-producing tumors showed a stratified or microfollicular pattern being accompanied by theca cells which had ultrastructural features of steroid-production, and these tumor cells exhibited immunoreactivity for bFGF. In contrast, tumors with no apparent hormone-production showed a solid or gyriform pattern without admixture of theca cells, and were negative for bFGF. LHR was expressed in both types of tumor. Accordingly, bFGF may play an important role in association with the theca cell component in granulosa cell tumors.