Objective: The authors investigated the natural history of asymptomatic nonfunctioning pituitary adenomas (NFPAs) with optic nerve compression.
Methods: This study retrospectively analyzed the natural history of asymptomatic NFPAs with documented optic nerve compression on MRI diagnosed between 2000 and 2016 from 2 institutions. The patients were followed up with regular endocrinological, ophthalmological, and radiological evaluations, and the endpoint was new endocrinopathy or neurological deficits.
Results: The study comprised 81 patients. The median age at diagnosis was 58.0 years and the follow-up duration was 60.0 months. As the denominator of overall pituitary patients, 2604 patients were treated with surgery after diagnosis at the 2 institutions during the same period. The mean initial and last measured values for tumor diameter were 23.7 ± 8.9 mm and 26.2 ± 11.4 mm, respectively (mean ± SD). Tumor growth was observed in 51 (63.0%) patients; however, visual deterioration was observed in 14 (17.3%) patients. Ten (12.3%) patients experienced endocrine deterioration. Fourteen (17.3%) patients underwent surgery for either visual deterioration (in 12 patients) or endocrine dysfunction (in 2 patients). After surgery, all patients experienced improvements in visual or hormonal function. The actuarial rates of treatment-free survival at 2, 3, and 5 years were 96.1%, 93.2%, and 85.6%, respectively. In the multivariate analysis, initial cavernous sinus invasion (HR 4.985, 95% CI 1.597-15.56; p = 0.006) was the only independent risk factor for eventual treatment.
Conclusions: The neuroendocrinological deteriorations were not frequent and could be recovered by surgery with early detection on regular follow-up in asymptomatic NFPAs with documented optic nerve compression on MRI. Therefore, conservative management could be an acceptable strategy for these tumors. Careful follow-up is required for tumors with cavernous sinus invasion.
Keywords: natural history; nonfunctioning; observation; optic nerve; pituitary adenoma; pituitary surgery.