Endocrine Abstracts

Background: Pituitary surgery is the initial treatment for the majority of patients with acromegaly. The UK acromegaly register data (UK-AR-2) suggests that surgical remission rates vary widely, with a marked improvement since 2000. The aim of this study was to assess the outcomes of first TSS for acromegaly in our centre over the past 5 years.

Methods: We retrospectively analysed data for all acromegaly patients who underwent first TSS between 2007-2011. Biochemical remission was defined as normalisation of IGF1 and GH nadir <1 mcg/l post-GTT, or <2 mcg/l (random GH or series mean), at 3 months after surgery. Post-operative imaging was reviewed and data regarding pre and post-operative pituitary hormone deficiencies was collected.

Results: Two surgeons performed 22 first TSS operations for patients with acromegaly over the 5 year period (2.2 acromegaly operations /year per surgeon), including eight microadenomas, six intrasellar (IS) macroadenomas and eight extrasellar (ES) macroadenomas.

Post-operative remission rates for GH were achieved in 88% of microadenomas, 67% of IS macroadenomas and 25% of ES macroadenomas. The corresponding percentages for IGF1 were 75, 50 and 12.5%, and for both IGF1 and GH 62.5, 50 and 12.5%.

Post-operatively, six patients with macroadenomas developed new pituitary axis deficiencies, whilst five patients with pre-operative pituitary axis deficiencies recovered function post-operatively.

Comparative data: Mean biochemical remission rates following TSS for acromegaly in eight published series since 2000 are 78% for microadenomas, 59% for intrasellar macroadenomas and 25% for extrasellar macroadenomas. Most published series are from larger centres. Some studies only report outcomes for multi-modal therapy for acromegaly.

Conclusions: How many pituitary centres the UK should have for optimal outcomes, and whether centres should have one or two pituitary surgeons, remains an active debate. Regular collection and reporting of surgical outcome data is essential to inform pituitary service provision.