Sertoli (sex cord) cell tumours are more prone to produce estrogens than androgens and typical markers AFP, bHCG are normal. Again, gynecomastia can occur or decreased libido.

Some 10% of both Sertoli and Leydig cell tumours are malignant, but prediction of behaviour can be difficult from pathology. Gonadoblastomas are gonadal stromal cell tumours with a mixed germ cell population and may also be hormonally functional. These are particularly associated with dysgenetic testicles and should therefore be reviewed by the urologist.

Initial work up (see diagnosis) should be along the lines of any testicular mass. In addition, patients may benefit from a baseline evaluation of serum testosterone, dehydroepiandrosterone, androstenediol, 17-hydroxyprogesterone, 11-desoxycortisol and urinary 17-ketosteroids. A few patients may have secondary alterations in LH/FSH.

The treatment of choice is radical inguinal orchidectomy ± retroperitoneal lymph node dissection. These tumours are only moderately chemotherapy sensitive and surgery remains the mainstay of treatment for these patients whenever feasible.