Abstract
Pituitary neuroendocrine tumours (PitNETs) are among the most common tumours of the central nervous system, yet data regarding surgical outcomes is limited for New Zealand (NZ). This study presents a 23-year single-surgeon case series of pituitary surgery. A retrospective analysis of 1,224 pituitary operations performed between August 1999 and July 2023 was conducted. Patient demographics, tumour characteristics, complications, and long-term outcomes were analysed. Statistical analyses included univariate and multivariate models. Pituitary neuroendocrine tumours (PitNETs) accounted for 88 % of cases (n = 1,087), including 612 non-functioning, 175 GH-producing, and 112 ACTH-producing tumours. The complications of transsphenoidal surgery for PitNETs included postoperative cerebrospinal fluid (CSF) leaks (7.3 %), permanent diabetes insipidus (3.4 %), meningitis (2.4 %), and visual deterioration (1.2 %). Carotid injury, stroke, and death within 30 days each occurred in less than 1 % of cases. Among 554 non-functioning PitNETs with surveillance imaging, 20 % recurred after a median follow-up of 3.7 years (IQR 1.6-7.7), with 10 % requiring reoperation. Recurrence was detected in 60 % of cases by five years and 90 % by ten years, of those who recurred. Age was protective, with each additional year reducing risk (HR = 0.98, p = 0.005). Cavernous invasion strongly predicted recurrence (HR = 2.9, p < 0.001). No significant association between ethnicity and recurrence was observed, including among Māori and Pasifika patients. Surgical remission in acromegaly was achieved in 76 % of microadenomas (median follow-up: 4.8 years; IQR: 1.0-6.8) and 75 % of macroadenomas (median follow-up: 4.3 years; IQR: 1.5-8.5). In Cushing's disease, remission was achieved in 82 % of microadenomas (median follow-up: 3.1 years; IQR: 0.8-9.2) and 75 % of macroadenomas (median follow-up: 4.0 years; IQR: 0.6-8.7). These findings demonstrate postoperative outcomes, complication rates, hormonal improvement, and tumour control, comparable to international standards.
