Endocrine Abstracts

Background: Hypopituitarism is often part of the presenting clinical manifestation for patients with non-functioning pituitary macroadenomas (NFPMs). Rate of recovery of hypothalamic-pituitary endocrine axes following therapy is uncertain with no clear predictive factors.

Aims: The aim of this study was to assess the degree of hypopituitarism recovery following surgery and radiotherapy in patients with NFPMs.

Methods: All patients treated with surgery and radiotherapy for NFPMs between 1987 and 2018 with more than 6 months follow-up were identified. A retrospective case note review was performed.

Results: In total, 383 patients were identified, 256 patients (256/383; 67%) were men. The median age was 57 years (IQR 48-67) with median follow-up of 5 years (IQR 2-9). At diagnosis, growth hormone deficiency occurred in 115 patients (115/273; 31%), hypogonadotropic hypogonadism in 160 patients (160/375; 43%), 132 patients (132/375; 36%) recorded to have adrenal insufficiency and 157 patients (157/375; 42%) developed secondary hypothyroidism. Panhypopituitarism was reported in 100 patients (100/377; 26%). Surgery only was performed in 318 patients (318/383; 83%) while 65 patients (65/383; 17%) needed surgery and radiotherapy to control tumour relapse. The degree of pituitary insufficiency recovery after NFPMs therapy is shown in the table. The combination of surgery and radiotherapy was associated with less likelihood of improvement in the case gonadotropins and TSH deficiencies as well as anterior hypopituitarism to patients who underwent surgery only. Notably, none of TSH deficient patients regained normal thyroid function post irradiation. Younger age was associated with a higher rate of improvement in gonadotroph deficiency (P=0.004), secondary hypocortisolism (P=0.01) and anterior hypopituitarism (P=0.006). Gender and extent of resection of NFPA on postoperative MRI scan was not related to pituitary recovery.

Conclsion: Recovery of pituitary hormone deficit may occur post NFPMs therapy. Factors associated with higher probability of reversal of pituitary hypofunction remain not fully understood. Patients should have regular endocrine evaluation post treatment to assess improvement in pituitary hypofunction and the need for long term replacement therapy.