Pituitary incidentalomas: a single-centre experience

Pituitary incidentalomas (PIs) are diagnosed in about 10% of the patients undergoing radiological investigation for non-pituitary disorders. The aim of this study was to describe the morphological and hormonal characteristics of PIs in a cohort of patients, followed up in a single centre from 1982-2009.

Retrospective analysis of electronic medical records of patients with PIs was carried out. All patients underwent basal and dynamic evaluation of the hypothalamus-pituitary axis. Mass size was assessed at yearly intervals.

Sixty-one patients (38 men/23 women, aged 53±2 years) were studied. The mean follow-up time was 48±8 months, and mean size of PIs was 20±2 mm. Twelve PIs (20%) were microadenomas, 48 (78%) were macroadenomas and one (2%) was a Rathke's cyst. The most common reasons that led to their discovery were headaches, dizziness, syncope, stroke and head injury. Forty-seven of the 61 PIs (77%) were non-functioning, 11 (18%) prolactinomas, and two (3%) GH-secreting adenomas. Hypopituitarism was present in 12% at diagnosis. Forty-eight per cent of the patients were submitted to surgery with conventional radiotherapy in 8%. Relapse in size was observed in 48% of the surgically treated patients. Of the PIs followed conservatively, 78% remained stable, 11% showed decrease and 11% increase in size during follow up. Hypopituitarism rose to 57% postoperatively.

Majority of PIs are non-functioning adenomas that remain stable in size. Relapse in size and hypopituitarism postoperatively are common. PIs, for which conservative management was initially considered appropriate, did not progress in size.