Purpose: Nonfunctioning pituitary adenomas (NFPAs) are among the commonest benign tumors of the pituitary. Hypopituitarism is frequently present at the time of diagnosis, and this has been attributed to stalk portal vessel compression and/or destruction of normal anterior pituitary cells. The aim of our study was to examine possible factors at diagnosis associated with the presence of hypopituitarism.
Methods: We retrospectively evaluated the records of patients with nonfunctioning pituitary macroadenomas from the database of our department. The inclusion criterion was the availability of imaging data regarding the extension of the lesion.
Results: A total of 148 patients (89 men, 60.1%) with nonfunctioning macroadenomas and available imaging data were identified. Mean age at diagnosis was 56.0 ± 14.5 years, and hypopituitarism was found in 66.2%. The maximum diameter of the adenoma, the patient's age at diagnosis, and compression of the optic chiasm were significant factors predicting the presence of hypopituitarism (OR 1.077, p = 0.006; OR 1.025, p = 0.045; and OR 2.893, p = 0.042, respectively). Suprasellar adenomas with extension to adjacent sinuses, although larger than those with only suprasellar extension, did not differ as to the degree of hypopituitarism. Moreover, in suprasellar adenomas, prolactin levels, albeit not independently, were also related to hypopituitarism (OR 1.035, p = 0.045).
Conclusions: In patients with NFPAs, prognostic factors related to increased risk of hypopituitarism are age at diagnosis, size of the adenoma, and most importantly the presence of suprasellar extension. These data accentuate the necessity for surgical decompression in case of suprasellar extension, in order, apart from saving visual acuity, to possibly avoid or reverse hypopituitarism.
Keywords: Nonfunctioning pituitary adenomas; Pituitary hormone deficiencies; Prolactin; Suprasellar extension.