Effects of long-term treatment with the gonadotropin-releasing hormone analog nafarelin in patients with non-functioning pituitary adenomas

The supposed origin of non-functioning pituitary adenomas (NFPA) from gonadotrophs prompted us to investigate the effects of the gonadotropin-releasing hormone (GnRH) analog nafarelin on hormonal and tumoral parameters in eight patients with NFPA, previously unsuccessfully operated and all hypogonadal. Nafarelin was administered intranasally for 1 year to all patients. Four patients received a dose of 1200 μg/day; the remaining four received 800 μg/day for 3 months, which was subsequently increased to 1200 μg/day. Basal gonadotropin and α-subunit (αSU) levels were low-normal. In four patients (nos. 1,2,3,5) nafarelin significantly lowered luteinizing hormone (LH) levels, and also follicle- stimulating hormone (FSH) in three of them (nos. 1,2,3)