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The outcomes of conservatively observed asymptomatic nonfunctioning pituitary adenomas with optic nerve compression.

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.