Exceedingly rare in testis, but yet juvenile GCT is the most common testicular tumor in infants <6 mos.
Adult GT occurs in patients 16 to 76 years (ave. 44 years).
Granulosa cells: relatively uniform round, ovoid or carrot-shaped cells with scant, light staining cytoplasm, nuclear groove (coffee bean).
Adult GT: Call-Exner bodies (tumor cells in ring-like or rosette-like arrangement) (image A) & (image B).
Juvenile GT: variably sized follicles lined by granulosa cells and outer theca cells containing basophilic to faintly eosinophilic luminal materials. Lacks Call-Exner bodies and nuclear grooves.
Most tumors have benign behavior; 20% metastasize.