CONTEXT

Pituitary adenomas are the most common lesions in the sellar region, but other pathologies need to be considered in the differential diagnosis.

OBJECTIVE

To assess the prevalence of unusual sellar masses in a large series of patients and identify clinicopathological factors that may aid the pre-operative diagnosis.

DESIGN

Retrospective case series.

PATIENTS

We analysed the records of 1469 transsphenoidal procedures performed between 1998 and 2009. One hundred sixteen cases (7·9%) were not pituitary adenomas.

MEASUREMENTS

Final pathological diagnosis.

RESULTS

One hundred sixteen patients (45 men, 71 women; mean age (±SD): 45 ± 17 years) with nonadenomatous lesions were divided into four major aetiological groups: cystic lesions (CYS) (53%); benign neoplasms (BEN) (22%); malignancies (MAL) (16%) and inflammatory lesions (INF) (9%). Rathke's cysts, the most common lesions, represented 42% of all cases. Twenty-five per cent of malignant lesions were metastases, and some of the MAL (e.g., fibrosarcoma, lung metastasis) had a radiographical appearance suggestive of a pituitary adenoma. The most common presenting symptoms were visual field impairment (51%) and headache (34%). Pre-operative pituitary dysfunction was present in 58% of cases, with hyperprolactinaemia (35%), hypogonadism (23%) and hypocortisolism (23%) found most frequently. Postoperative resolution of headache and visual symptoms occurred in 63% and 65% of patients, respectively. Hyperprolactinaemia resolved in 77% of cases.

CONCLUSIONS

A substantial minority of sellar masses are not pituitary adenomas. While they frequently present with the symptoms, hormone abnormalities and radiographical appearance typical of pituitary tumours, the possibility of a nonadenomatous lesion needs to be considered in the differential diagnosis.