Juvenile Granulosa Cell Tumor : Microscopic
Microscopically, juvenile granulosa cell tumor shows a lobular growth pattern at low magnification. Scattered within the solid cellular areas are follicles of various sizes and shapes filled with eosinophilic or basophilic secretions that are mucicarmine positive. The follicular cysts are lined by several layers of cells resembling granulosa cells (inner part of the cyst wall) or theca cells (outer portions of the cyst wall).
In nonfollicular areas, the tumor cells usually grow in diffuse sheets but can show cord-like or reticular patterns. There is scant stroma in the background which may be fibrous, hyalinized or myxoid. Hemosiderin-laden macrophages may be present.
Rare patterns include: tumor regression with extensive stromal hyalinization; papillary architecture; basaloid morphology; spindle cells; microcystic areas; and hyaline globules.