<unk> s are tumours that arise from<unk> <unk> s. They are estrogen secreting tumors and present as large, complex, ovarian masses. These tumours are part of the sex cord-gonadal stromal tumour or non-epithelial group of tumours. Although<unk> <unk> s normally occur only in the ovary,<unk> s occur in both ovaries and testicles (see ovarian cancer and testicular cancer). These tumours should be considered malignant and treated in the same way as other malignant tumours of ovary. The ovarian disease has two forms, juvenile and adult, both characterized by indolent growth, and therefore has high recovery rates. The staging system for these tumours is the same as for epithelial tumours and most present as stage I. The peak age at which they occur is 50–55 years, but they may occur at any age. Juvenile<unk>  is a similar but distinct rare tumour. It too occurs in both the ovary and testis. In the testis it is extremely rare, and has not been reported to be malignant. Although this tumour usually occurs in children (hence its name), it has been reported in adults.
Granulosa cell tumour
Sertoli cell tumour
Leydig cell tumour
Gonadoblastoma
Metanephric adenoma
Germ cell tumor
Sertoli–Leydig cell tumour
Ovarian germ cell tumors