Leydig Cell Tumor:
The most common nongerminal tumor of the testis, derived from the Leydig cells. It is rarely malignant. This tumor appears among 1-3% of testicular tumors and although they may be seen in children, the median age of appearance is 60 years. They are sometimes seen in women as ovarian tumors. Clinically, symptoms are usually related to the endocrine abnormalities induced by this tumor. (From Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1597)
