Endocrine Abstracts

Background: Non-functioning pituitary macroadenomas (NFPMs) may present with hypopituitarism. Pituitary surgery and radiotherapy pose an additional risk to pituitary function.

Aims: The aim of this study was to assess the incidence of hypopituitarism pre-operatively and the impact of surgery and radiotherapy on pituitary function.

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: Overall, 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). 58 patients (58/377, 15%) presented with pituitary insufficiency, however, on endocrine evaluation, 235 patients (235/377; 62%) had evidence of pituitary impairment. Growth hormone deficiency occurred in 115 patients (115/273; 31%), hypogonadotropic hypogonadism in 161 patients (161/375; 43%), 132 patients (132/375; 36%) recorded to have adrenal insufficiency and 157 patients (157/375; 42%) developed secondary hypothyroidism. Anterior hypopituitarism was reported in 100 patients (100/377; 26%). With regards to treatment modality; 318 patients (318/383; 83%) were treated with surgery alone and 65 patients (65/383; 17%) were treated with surgery and radiotherapy. Histological analysis showed gonadotroph adenomas in 271 patients (371/383; 97%) and plurihormonal adenomas in 12 patients (12/383; 3%). At latest follow-up, 105 patients (105/383; 27%) had no evidence of pituitary impairment post therapy while 278 patients (278/383; 73%) suffered endocrine dysfunction. Patients who were treated with surgery and radiotherapy had a greater degree of partial and complete adenohypophysial hormone deficit than those treated with surgery alone as demonstrated in the table:

Conclusion: Non-functioning pituitary macroadenomas are associated with significant degree of hypopituitarism at time of diagnosis as well as post therapy. The combination of surgery and radiotherapy are associated with higher risk of pituitary dysfunction. Regular endocrine evaluation and lifelong follow-up is required following NFPMs treatment to screen for hormone deficiency and provide appropriate replacement therapy.