Non-functioning pituitary adenomas: a single center experience

To describe the clinical imaging and hormonal characteristics and the natural course of patients with clinically non-functioning pituitary adenomas (NFPAs) presenting at our department from 1984 to 2009.

Retrospective review of electronic medical records of patients with NFPAs. The patients underwent basal and dynamic evaluation of the hypothalamic-pituitary axis. Size and functional alterations were estimated at yearly intervals.

114 patients (55 men and 59 women, aged 47±2) were studied. The mean follow-up time was 55±6 months (range 0-240). 45% of the adenomas were incidentally discovered and 75% were macroadenomas (73% with extrasellar extension). At diagnosis, 53% had headache and 76% of those with macroadenomas had visual field defects. Disruption of ≥1 pituitary axes was identified in 31% of patients at diagnosis. Surgery was performed in 59% and radiotherapy in 9% of the cases. 88% of surgically treated patients reported improvement in headache and 59% in visual fields. However, the prevalence of permanent diabetes insipidus increased from 2% at diagnosis to 15% postoperatively. The prevalence of ≥1 pituitary deficiencies and panhypopituitarism increased significantly postoperatively. 58% of the adenomas relapsed in size. 29% of the patients were managed conservatively and tumor size remained stable in 83% of them.

The majority of NFPAs not selected for surgery at diagnosis remained stable in size. Pituitary dysfunction and visual defects at diagnosis were common. Surgical debulking led to clinical improvement, but relapse occurred in 2/3 of the cases.