Endocrine Abstracts

Introduction: There is scarcity of data on the recurrence and/or progression (R/P) rate in nonfunctioning pituitary adenomas (NFPAs) after surgery and the risk factors that can predict this outcome. So the aim of this study was to analyze a large series of NFPAs with a long follow-up after surgery, focusing on the evaluation of R/P rate and the risk factors associated with it.

Methods: Retrospective cohort analysis of 164 patients with NFPAs from 3 different centers in Northern Spain who underwent surgery between 1987–2014. The main outcomes were R/P rate during follow-up using Kaplan-Meier estimator and the univariate and multivariate analysis of risk factors that could be involved with R/P.

Results: R/P was detected in 70 patients (43%) after surgery, over a median clinical follow-up of 8 years (1–27), the median time to R/P was 4.1 years. Recurrence-free survival was 65%, 49%, 42% and 32% at 5, 10, 15 and 20 years after surgery, respectively. The univariate analysis identified the following R/P risk factors: pituitary apoplexy and visual impairment at diagnosis; and as protective factor: RT after surgery in patients with subtotal resection (STR) but the multivariate Cox analysis only confirmed as independent factors: visual impairment (hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.1–4.2; P=0,02) and RT in patients with STR after surgery (HR 0.4, 95% CI 0.21–0.89; P=0.02).

Conclusions: Long term follow-up in NFPAs after surgery is mandatory because R/P occurs in a large percentage of these patients and the risk does not disappear in the long term. Our study suggests that this follow-up has to be more rigorous in patients with visual impairment at diagnosis because they have the highest risk of R/P. RT could decrease this risk specially in those patients with subtotal tumor resection.