Endocrine Abstracts

Introduction: Non-functioning pituitary adenomas (NFPAs) constitute a large proportion of pituitary adenomas and can lead to hypopituitarism and visual field defects. Trans-sphenoidal surgery is the treatment of choice but as a consequence patients may suffer from long-term hormone deficiencies and diabetes insipidus. We sought to examine clinical, pathological, and imaging characteristics of those presenting with NFPAs and subsequent post-surgical outcomes.

Methods: Clinical data was collected from NHS Lothian care records for patients who underwent primary trans-sphenoidal surgery for NFPAs between 2005 and 2014 (n=81). This retrospective analysis looked at patient characteristics, tumour pathology, tumour imaging and biochemical profiles. Mean follow-up was 5.52±2.41 years.

Results: Visual disturbance and headache were the commonest presenting symptoms at 67 and 30% respectively. Pathological analysis identified most tumours to be either gonadotroph cell (38.8%) or null cell (37.5%) adenomas. Repeat surgery was required in 6.2% of patients. The percentage of patients with hormone deficiencies decreased from 64.2 to 56.8% after surgery. An inadequate day 3 morning cortisol of <460 nmol/l had a low positive predictive value of 28.1% for 6 week postoperative adrenocorticotrophic hormone deficiency. Those patients who developed hypopituitarism at follow up were more likely to be male than female (76.2 vs 35.9%, P≤0.001) due to the large amount of males with hypogonadism. Patients with hormone deficiencies at follow up had larger preoperative tumours (30.4±8.3 mm vs 24.7±8.9 mm, P=0.016). Diabetes insipidus postoperatively was associated with higher preoperative sodium levels (141.0±4 vs 139.0±5, P=0.042).

Conclusions: These results show encouraging postoperative outcomes and can help clinicians identify those at risk of complications. Active follow-up should be targeted at those who are male, have large preoperative tumours and higher preoperative sodium levels.