The role of stereotactic radiotherapy in patients with growth hormone-secreting pituitary adenoma

J Clin Endocrinol Metab. 2008 Jul;93(7):2546-52. doi: 10.1210/jc.2008-0135. Epub 2008 Apr 15.


Context: Single-session stereotactic radiotherapy (SR) may be a potential adjuvant treatment in acromegaly.

Objective: We analyzed the safety and efficacy of SR in patients who had previously received maximal surgical debulking at our center.

Design: The study was a retrospective analysis of hormonal, radiological, and ophthalmologic data collected in a predefined protocol from 1994 through 2006.

Setting: The study was performed at a university hospital.

Patients: Eighty-three acromegalic patients, 52 women and 31 men, with a mean age of 42.6 +/- 1.2 yr, participated in the study. The median follow-up was 69 months (interquartile range 44-107 months).

Intervention: The patients were treated with SR for residual or recurrent GH-secreting adenoma.

Main outcome measure: Normalization of age- and sex-adjusted IGF-I levels together with a basal GH level below 2.5 microg/liter without concomitant GH-suppressive drugs was the goal of therapy.

Results: Fifty patients (60.2%) reached the main outcome of the study. The rate of remission was 52.6% at 5 yr [95% confidence interval (CI) 40.6-64.6%]. Another 13 patients (15.7%), who were resistant to somatostatin analogs, were in remission after SR. Multivariate analysis showed that low basal GH and IGF-I levels were associated with a favorable outcome. No serious side effects occurred after SR. The 5-yr cumulative risk of new onset hypogonadism, hypothyroidism, or hypoadrenalism was 3.6% (95% CI 0-8.6%), 3.3% (95% CI 0-7.7%), and 4.9% (95% CI 0-10.4%), respectively.

Conclusion: In a highly selected group of acromegalic patients, SR treatment had good efficacy and safety. This may lead to reconsider the role of SR in the therapeutic algorithm of acromegaly.

MeSH terms

  • Adenoma / blood
  • Adenoma / pathology
  • Adenoma / surgery*
  • Adult
  • Female
  • Growth Hormone-Secreting Pituitary Adenoma / blood
  • Growth Hormone-Secreting Pituitary Adenoma / pathology
  • Growth Hormone-Secreting Pituitary Adenoma / surgery*
  • Human Growth Hormone / blood
  • Humans
  • Insulin-Like Growth Factor I / analysis
  • Male
  • Radiosurgery* / adverse effects
  • Retrospective Studies


  • Human Growth Hormone
  • Insulin-Like Growth Factor I