Gamma Knife radiosurgery for hypothalamic hamartoma preserves endocrine functions

International audience; Gamma Knife radiosurgery (GK) is an effective treatment for hypothalamic hamar-toma. No precise data are available on the risk of endocrine side effects of this treatment. In this study, 34 patients with hypothalamic hamartoma (HH) were followed prospectively at the Department of Endocrinology, La Timone Hospital, Marseille, France, for a mean follow-up of >2 years (mean AE standard deviation [SD] 3.6 AE 2 years). Initial pre-and post-GK radiosurgery evaluations were performed, including weight, body mass index (BMI), and a complete endocrinological workup. At diagnosis, eight patients presented with central precocious puberty at a mean age of 5.4 AE 2.4 years. At the time of GK (mean age 18.2 AE 11.1 years), two patients previously treated with surgery presented with luteinizing hormone/follicle-stimulating hormone (LH/FSH) deficiency. After GK, only one patient presented with a new thy-rotropin-stimulating hormone (TSH) deficiency, 2 years after the procedure. The other pituitary axes remained normal in all but two patients (who had LH/FSH deficiency prior to GK). There was no significant difference between pre-and post-GK mean BMI (26.9 vs. 25.1 kg/m 2 , p = 0.59). To conclude, in this group of 34 patients, GK did not induce major endocrinologic side effects reported with all the other surgical techniques in the literature. It is, thus, a safe and effective procedure in the treatment of hypothalamic hamartoma.