Stereotactic radiosurgery for acromegaly

J Clin Endocrinol Metab. 2014 Apr;99(4):1273-81. doi: 10.1210/jc.2013-3743. Epub 2014 Jan 28.


Context: The role of stereotactic radiosurgery (SRS) in acromegaly is being assessed.

Objective: We evaluated the efficacy and safety of SRS for patients with acromegaly. Prognostic factors related to outcomes were also analyzed.

Design: This was a retrospective study of patients treated with SRS at the University of Virginia; the data were collected from 1989 to 2012, with a median follow-up of 61.5 months.

Patients: A total of 136 patients underwent SRS for acromegaly. Diagnosis of acromegaly was based on the combination of clinical features and biochemical assessment, including the serum GH level and age- and gender-matched serum IGF-1 level. All patients underwent a complete endocrine evaluation, neuroimaging study, and ophthalmic examinations before SRS.

Main outcome measures: After withdrawal of GH- or IGF-1-altering medications, patients who had an oral glucose tolerance test GH of < 1.0 ng/mL or normal IGF-1 were considered in remission. Post-radiosurgical hypopituitarism was defined as a decrease in one or more hormones below normal.

Results: With a median follow-up of 61.5 months, 65.4% of the patients achieved remission. The mean time to remission was 27.5 months. The actuarial remission rates at 2, 4, 6, and 8 years after radiosurgery were 31.7, 64.5, 73.4, and 82.6%, respectively. Favorable prognostic factors for remission included a higher margin radiation dose, higher maximum dose, and lower initial IGF-1 level. New pituitary hormone deficiency occurred in 43 patients (31.6%); two patients (1.5%) developed panhypopituitarism. Corresponding risk factors for new pituitary hormone deficiency were a margin dose > 25 Gy and tumor volume > 2.5 mL. Other complications included an adverse radiation effect in one patient, visual deterioration in four, and new oculomotor nerve palsy in one.

Conclusion: SRS affords a reasonable rate of endocrine remission in patients with acromegaly and generally does so with a low rate of adverse effects.

Publication types

  • Evaluation Study

MeSH terms

  • Acromegaly / diagnosis
  • Acromegaly / epidemiology
  • Acromegaly / surgery*
  • Adenoma / diagnosis
  • Adenoma / epidemiology
  • Adenoma / surgery
  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Growth Hormone-Secreting Pituitary Adenoma / diagnosis
  • Growth Hormone-Secreting Pituitary Adenoma / epidemiology
  • Growth Hormone-Secreting Pituitary Adenoma / surgery
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Prognosis
  • Radiosurgery* / adverse effects
  • Retrospective Studies
  • Treatment Outcome
  • Young Adult