Gonadal stromal tumours of the testis comprise about 6% of adult testis tumours, but 20% of gonadal stromal tumours occur in children. Because of the rare nature of these tumours, their pathology should be reviewed. Patients will be seen at BC Cancer Agency on request. Patients may present with a painless testis mass, but almost 20% will present with symptoms referable to endocrine imbalance. Leydig (interstitial cell) tumours are particularly prone to produce androgen (but may produce estrogen, progesterone, corticosteroids) and therefore in children can cause precocity or later in life masculinization. Gynecomastia can also occur. Up to 8% of Leydig cell tumours are bilateral.

Lymphomas and paratesticular rhabdomyosarcomas are dealt with in other sections of the policy manual.