Gamma-knife radiosurgery in acromegaly: the results from the Croatian acromegaly registry.

The aim of our study was to evaluate the efficacy and safety of Leksell gamma-knife radiosurgery in the treatment of residual growth hormone-secreting pituitary adenomas after the surgery. We conducted a retrospective analysis of 23 acromegaly patients treated with gamma-knife radiosurgery between 1996 and 2019. The therapeutic success of radiosurgery was defined as IGF-1 normalization without suppressive medication (complete response) or as IGF-1 normalization with medication (partial response). The median follow-up was 57 (10–198) months. Complete response was achieved in 11 patients (47.8%) with actuarial remission rates of 17.4%, 26.1%, 39.1% and 47.8% at 1, 2, 4, and 7 years, respectively. The median time to complete the response was 21 (6–85) months. Partial response was achieved in another nine patients (39.1%) after a median time of 48 (6–144) months from radiosurgery. Patients who achieved complete remission had significantly lower IGF-1 levels before radiosurgery (p = 0.016) as well as smaller tumour volume (p = 0.016) and radiologically less invasive tumours (p = 0.022) in comparison to patients who did not achieve IGF-1 normalization. Tumour growth control after radiosurgery was established in all patients. During the follow-up, new hormone deficiencies were found in seven patients (30.4%) which corresponds to the incidence of one new case of hypopituitarism per 7.1 patient years. Gamma-knife radiosurgery offers endocrine remission and tumour growth control in a substantial proportion of patients with GH-secreting adenomas. Given the high cost of life-long medical treatment and a moderate risk of radiation-induced side effects, radiosurgery for growth hormone-secreting pituitary adenomas should be considered in all patients with residual tumours. [ABSTRACT FROM AUTHOR]

Copyright of British Journal of Neurosurgery is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)