Outcome of gamma knife radiosurgery in 82 patients with acromegaly: correlation with initial hypersecretion.
BACKGROUND
Because surgical and medical therapies of acromegaly all have specific limitations, radiotherapy has been used as an adjunctive strategy. Stereotactic radiosurgery has not yet been widely evaluated.


OBJECTIVE
The objective was to perform an analysis of long-term hormonal effects and tolerance of gamma knife radiosurgery.


METHODS
Eighty-two patients were prospectively studied over a decade, with a mean follow-up of 49.5 months.


METHODS
All patients were treated at the Department of Functional Neurosurgery of Marseille, France.


METHODS
The patients included 82 with active acromegaly, of whom 63 had previous transsphenoidal surgery.


METHODS
Intervention included radiosurgery using the Leksell Gamma Unit B model.


METHODS
Remission was diagnosed when mean GH levels were less than 2 ng/ml and IGF-I was normal for age off somatostatin agonists (at least 3 months).


RESULTS
Seventeen percent of the patients were in remission without any treatment. Twenty-three percent previously uncontrolled on somatostatin agonists fulfilled the same criteria after gamma knife while maintained on medical treatment. Initial GH and IGF-I levels off somatostatin agonists were significantly higher in uncured than in remission group (P = 0.01 and 0.047, respectively). Withdrawal of somatostatin agonists at the time of radiosurgery had no incidence on the outcome. No significant difference was found in success rate whether patients had previously been treated or not. Long-term side effects included complete (n = 2) or partial (n = 12) hypopituitarism diagnosed 1-7 yr after gamma knife.


CONCLUSIONS
Gamma knife radiosurgery may represent a therapeutic approach in patients with moderate initial or residual GH hypersecretion.
Castinetti
Frédéric
F
Federation of Endocrinology, Diabetes, Metabolic Diseases and Nutrition, Hôpital de la Timone, Centre Hospitalier Universitaire de Marseille and Faculté de Médecine, Université de la Méditerranée, Marseille, France.
Taieb
David
D
Kuhn
Jean-Marc
JM
Chanson
Philippe
P
Tamura
Manabu
M
Jaquet
Philippe
P
Conte-Devolx
Bernard
B
Régis
Jean
J
Dufour
Henry
H
Brue
Thierry
T
D000172:Acromegaly / Q000601:surgery*; D000236:Adenoma / Q000378:metabolism / Q000601:surgery*; D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D019382:Human Growth Hormone / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000378:metabolism / Q000601:surgery*; D011446:Prospective Studies; D016634:Radiosurgery / Q000009:adverse effects; D012074:Remission Induction; D016896:Treatment Outcome
D019382:Human Growth Hormone