R004

Outcomes of Transsphenoidal Surgery for Growth Hormone-secreting microadenomas at our centre: A comparison with the literature.

H Fraser, N Mendoza, K Meeran, N Martin, K Wynne – Imperial College Healthcare NHS Trust

Background: Growth Hormone (GH)-secreting adenomas cause significant morbidity and premature mortality. Transsphenoidal Surgery (TSS) is the most effective and subsequently first line treatment for GH-secreting adenomas. Complete resection of a GH-secreting adenoma results in a patient mortality no higher than the general population, provided strict remission criteria are used. Our centre is a high volume, specialist centre with a single pituitary surgeon. The aim of our study was to assess the outcomes of TSS in patients with GH-secreting microadenomas.

Methods: We retrospectively analysed data of 17 patients who underwent TSS for GH-secreting microadenomas at our centre between 1^st January 1995 and 31^st December 2010. Remission was defined as a GH nadir <0.6mcg/L during an OGTT or a mean GH <1.7mcg/L during a GHDC. Data regarding pre- and post-operative imaging, medical therapy and radiotherapy was collected.

Results: Remission was achieved in 71% of patients (12 of 17 patients). No mortalities, major or minor complications occurred. TSH, ACTH and ADH deficiency were present pre-operatively in 19%, 19% and 0% and post-operatively in 19%, 50% and 0% of patients, respectively. Thus, five patients required hydrocortisone post-operatively as a consequence of surgery. One patient had a recurrence of acromegaly during the follow-up period.

Discussion: In the literature, remission rates for GH-secreting microadenomas range from 59%-91%. However, remission criteria vary. At our centre, TSS for GH-secreting microadenomas achieves high remission rates with very low complication rates.