Clinical significance of thickened sphenoid sinus mucosa in Rathke's cleft cyst

BACKGROUND: To determine the clinical significance of thickening of the sphenoid sinus mucosa (TSSM) in Rathke's cleft cyst (RCC). METHODS: We retrospectively reviewed patients with pituitary lesions. A total of 99 patients, who underwent surgery of pituitary lesions between 2008 and 2015, were analyzed to evaluate the clinical significance of TSSM using magnetic resonance imaging. The patients with TSSM were evaluated for their characteristics. RESULTS: Of the 99 operations, 15 patients with paranasal sinusitis, direct invasion to the sellar floor, and/or a history of transsphenoidal surgery were excluded. There were 51 pituitary adenomas (PAs), 18 RCCs, and 15 other tumors. TSSM was observed in 6 patients (7.1%). Pathologies included 3 RCCs (16.7%), 1 PA (2.0%), and 2 other lesions. Three RCCs were especially analyzed. The pituitary dysfunction was found in all 3 patients with TSSM, whereas that was noted in 2 of 15 patients (13.3%) without TSSM. The sensitivity was 60%, specificity was 86.7%, and the positive predictive value was 100%. There was no significant difference in the age, thickness of TSSM, symptoms, and squamous metaplasia between patients with and without TSSM. CONCLUSIONS: TSSM occurs more frequently in RCCs than in PAs. TSSM can potentially suggest hypopituitarism in RCCs. The surgical and/or endocrinological interventions are required for preventing further endocrine deterioration.