Transsphenoidal surgery is the first-line treatment of acromegaly. Adjunctive radiotherapy can be necessary when surgery is ineffective to avoid a prolonged medical treatment. Several studies reported long-term extra-pituitary side-effects of conventional radiotherapy. However, none has evaluated potential side-effects induced by Gamma Knife radiosurgery, a highly precise stereotactic technique, that has been used as an effective treatment of acromegaly.

Aims of the study: To determine potential long-term (superior to 10 years) extra-pituitary side-effects of Gamma Knife radiosurgery in patients treated for Acromegaly.

Methods: Transversal exposed/unexposed study. Exposed patients have been treated by Gamma Knife Radiosurgery after unsuccessful surgery 10-20 years before inclusion, whereas unexposed patients have been treated by somatostatin analogs after unsuccessful surgery for at least 10 years before inclusion. 80 Patients (40 patients/group) will be evaluated in terms of cognitive dysfunction, quality of life, secondary tumor, stroke, pituitary deficits and growth hormone control of hypersecretion. Recruitment is planned to last for 2 years.

Expected results: We should be able to determine whether Gamma Knife radiosurgery is a long-term safe technique. This result might modify the management and follow-up of patients with acromegaly unsuccessfully treated by surgery.

Inclusion Criteria:

• Subject, man or woman, whose age is greater than or equal to 18 years;
• Subject has a combination of defined values plus Insulin Like Growth Factor-1 and no braking growth hormone (<1.2 milli-International unit/L) during an oral glucose tolerance acromegaly.
• Exposed: Subject with a surgically treated in remission with or without drug treatment somatostatinergic, acromegaly who received treatment with Gamma Knife radiosurgery within not less than 10 years and less than or equal to 20 years.
• Not exposed: Subject with a surgically treated acromegaly controlled by treatment somatostatinergic, not having received Gamma Knife radiosurgery.
• Subjects with thyroid under standardized assessment Levothyrox® inclusion in case of deficit associated thyroid stimulating;
• Topic supported in a project partner services;
• Subjects who have signed a written informed consent and agreeing to abide by the instructions of the protocol.

Exclusion Criteria:

• Minor or over the age of 75 years subject,
• Subjects with acromegaly resistant to somatostatinergic, or that required power is pegvisomant or cabergoline
• Subjects who received two pituitary neurosurgical treatment or treatment with conventional radiotherapy or radiosurgery treatments 2
• Pregnant or lactating woman,
• Topic is not affiliated with the social security system, or private about freedom;
• Subject refusing to participate in the study or not signing the informed consent;
• Subject with malignant disease known evolutionary