Endocrine Abstracts

Background: Transsphenoidal surgery is the primary therapy in majority of Acromegaly patients with GH-secreting somatotroph adenomas. Reported outcomes of surgery show an initial remission rate of 40–50% for macroadenomas and >85% for microadenomas. Rates of hypopituitarism following endoscopic pituitary decompression vary between 5 and 25%. Invasion of cavernous sinus indicates the tumour is unlikely to be resectable.

Methods: We audited the results of endoscopic pituitary decompression for patients with biochemically proven Acromegaly between January 2015 and January 2018 at the Wessex Neurological Centre. Biochemical tests were reviewed to establish remission rates and post-operative hypothalamus-pituitary-adrenal (HPA) integrity. Remission rates were analysed using both historical criteria used in literature (defined as a random GH less than 5 μ/l or <2 μ/l during oral glucose tolerance test (OGGT) and normalised IGF-1), as well as latest remission criteria in accordance with Endocrine Society guidelines 2014 (A normal IGF value and random GH < 1 μg/l or GH nadir of < 0.4 5 μ/L during OGGT.). In addition patients were subdivided into 2 groups according to pre-operative MRI findings, namely either intrasellar or extrasellar subgroups.

Results: 29 cases with Acromegaly undergoing surgery were analysed. 17 had intrasellar tumours, 12 had extrasellar tumours, 75% of these invaded the cavernous sinus. Remission rates in patients with intrasellar tumours was 82% using historical criteria, 76% using latest criteria and none had impairment of HPA. Of the patients with extrasellar tumours 42% had biochemical cure using old criteria and 17% using latest one, 40% had impaired HPA axis, including one patient who presented with apoplexy. Overall HPA dysfunction is 16% for both groups combined.

Conclusion: The Wessex regional neurosurgical pituitary service has comparable Acromegaly remission rates post pituitary surgery to that in published series, with low postoperative HPA dysfunction rates.