Isosexual precocious pseudopuberty secondary to a testosterone-secreting Leydig cell testicular tumour: true isosexual development early after surgery.

The paper reports on a 6-year-old boy with precocious pseudopuberty due to androgen hypersecretion by a testicular interstitial cell tumour. Steroidogenesis, characterized by high testosterone, dihydrotestosterone, androstenedione, dehydroepiandrosterone and 17-hydroxyprogesterone plasma levels, was not modified by ACTH, dexamethasone or HCG administration. Gonadotropins were subnormal and unresponsive to LRH stimulation. TSH and prolactin levels were normal both in basal and dynamic conditions. The hormonal profile progressively returned to prepubertal value and persisted normal for 6 months after removal of the tumour. The patient entered puberty spontaneously at 7,6/12 years showing a normal pubertal basal and LRH stimulated FSH and LH and a pubertal circadian rhythm of both gonadotropins and testosterone.