Juvenile granulosa cell tumor in association with a high serum inhibin level

Inhibin is a glycoprotein hormone produced mainly by ovarian granulosa cells. Recently measurement of serum inhibin levels was made possible by radioimmunoassay. We describe a patient with a juvenile granulosa cell tumor, a distinctive and rare form of granulosa cell tumor. This patient's serum inhibin level was extremely high preoperatively and returned to normal after the tumor was resected. This case suggests that serum inhibin level may be a useful marker of granulosa cell tumors.