Gamma knife radiosurgery for medically and surgically refractory prolactinomas.
OBJECTIVE
Experience with gamma knife radiosurgery (GKRS) for prolactinomas is limited because of the efficacy of medical and surgical intervention. Patients who are refractory to medical and/or surgical therapy may be treated with GKRS. We characterize the efficacy of GKRS for medically and surgically refractory prolactinomas.


METHODS
We reviewed our series of patients with prolactinomas who were treated with GKRS after failing medical and surgical intervention who had at least 1 year of follow-up.


RESULTS
Twenty-three patients were included in analysis of endocrine outcomes (median and average follow-up of 55 and 58 mo, respectively) and 28 patients were included in analysis of imaging outcomes (median and average follow-up of 48 and 52 mo, respectively). Twenty-six percent of patients achieved a normal serum prolactin (remission) with an average time of 24.5 months. Remission was significantly associated with being off of a dopamine agonist at the time of GKRS and a tumor volume less than 3.0 cm3 (P < 0.05 for both). Long-term image-based volumetric control was achieved in 89% of patients. Complications included new pituitary hormone deficiencies in 28% of patients and cranial nerve palsy in two patients (7%).


CONCLUSIONS
Clinical remission in 26% of treated patients is a modest result. However, because the GKRS treated tumors were refractory to other therapies and because complication rates were low, GKRS should be part of the armamentarium for treating refractory prolactinomas. Patients with tumors smaller than 3.0 cm3 and who are not receiving dopamine agonist at the time of treatment will likely benefit most.
Pouratian
Nader
N
Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia, USA.
Sheehan
Jason
J
Jagannathan
Jay
J
Laws
Edward R
ER
Steiner
Ladislau
L
Vance
Mary L
ML
D000293:Adolescent; D000328:Adult; D000368:Aged; D018491:Dopamine Agonists / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000706:statistics & numerical data; D018579:Patient Selection; D010902:Pituitary Gland / Q000473:pathology* / Q000528:radiation effects / Q000601:surgery*; D010911:Pituitary Neoplasms / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology / Q000503:physiopathology; D011388:Prolactin / Q000097:blood / Q000378:metabolism; D015175:Prolactinoma / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D011829:Radiation Dosage; D016634:Radiosurgery / Q000009:adverse effects / Q000592:standards* / Q000706:statistics & numerical data*; D012074:Remission Induction / Q000379:methods; D012189:Retrospective Studies; D017211:Treatment Failure; D016896:Treatment Outcome
D018491:Dopamine Agonists; D011388:Prolactin