Pituitary Function at Presentation and Following Therapy in Patients with Non-functional Pituitary Adenomas: A Single Centre Retrospective Cohort Study

Background:Non-functioning pituitary macroadenomas (NFPMs) may present with hypopituitarism. Pituitary surgery and radiotherapy pose an additional risk to pituitary function.ObjectivesTo assess the incidence of hypopituitarism at presentation, the impact of treatment, and the likelihood of endocrine recovery during follow-up.MethodsAll patients treated surgically with and without radiotherapy for NFPMs between 1987 and 2018 who had longer than 6 months follow-up were identified. Demographics, presentation, investigation, treatment, and outcomes were collected.ResultsIn total, 383 patients were identified. The median age was 57 years with a median follow-up of 8 years. Preoperatively, 235 patients (235/377; 62%) had evidence of at least one pituitary deficiency. Anterior panhypopituitarism was more common in men (p =0.001), older patients (p =0.005), and in those with adenomas extending beyond the sella turcica (p =0.05). Patients treated with surgery and radiotherapy had a higher incidence of all individual pituitary hormone deficiency and anterior panhypopituitarism as well as significantly lower GH, ACTH, and TSH deficiencies free survival probability than those treated with surgery alone. Recovery of central hypogonadism, hypothyroidism, and anterior panhypopituitarism was also less likely to be reported in those treated with surgery and radiotherapy.ConclusionNFPMs are associated with significant degree of hypopituitarism at time of diagnosis and post therapy. The combination of surgery and radiotherapy is associated with higher risk of pituitary dysfunction. Recovery of pituitary hormone deficit may occur after surgical treatment. Patients should have regular ongoing endocrine evaluation post-treatment to assess changes in pituitary function and the need for long-term replacement therapy.