Endocrine Abstracts

Background: Hypopituitarism is a potential complication of trans-sphenoidal adenomectomy (TSA). Recovery of pituitary function can occur, and reassessment is required to avoid unnecessary hormonal replacement. However, frequency of re-testing is variable across centres. Aim of this study was to determine recovery rates and time to recovery of hypothalamo-pituitary adrenal (HPA) and thyroid axis after TSA.

Methods: We performed a single-centre, retrospective analysis of patients undergoing TSA from January 2016 to March 2018. Patients with apoplexy, corticotroph adenomas or radiotherapy were excluded. Thyroid and HPA axis adequacy was assessed with TSH/freeT₄ measurements and short synacthen tests (SST), performed pre-TSA and at 6-weeks, 3-, 6-, 9- and 12-months post-operatively.

Results: Data on 108 patients (mean age 53±17 years; 64M) were analysed. Macroadenomas occurred in 102 (94.4%), microadenoma in 6 (5.6%). Histology confirmed gonadotroph (49.1%), somatotroph (11.1%), plurihormonal (12%), lactotroph (7.4%), meningioma (2.8%), craniopharyngioma (13%), thyrotroph (1.9%) and metastatic malignancy (2.8%). 67.6% of patients had normal pre-op HPA function and 67.2% had normal HPA function at 6-weeks post-op. Among patients with abnormal pre-op HPA function, 32.1% (9/28) recovered at 6-weeks. 43.3% of our cohort failed SST at 6-weeks. Among them, 23.8%, 11.9% and 14.2% recovered at 3-, 6-, and 12-months respectively. Normal thyroid functions noted in 64.6% of patients pre-operatively and in 94.9% 6-weeks post-operatively. Conversely, 18.8% of patients having abnormal pre-op thyroid function recovered. Among patients recovering HPA axis function at 6-weeks, 83.6% also recovered thyroid axis (OR 3.7, P<0.01).

Conclusions: After TSA, HPA and thyroid axis recovery occur more frequently in patients with normal pre-op function. Recovery of the HPA axis positively predicts thyroid axis recovery. HPA axis recovery can occur at 12-months post-TSA, emphasizing the importance of periodic reassessment to avoid unnecessary hydrocortisone replacement in those who could eventually regain function.