Proton Magnetic Resonance Spectroscopy Characterization of Rathke’s Cleft Cysts (RCCs): Relevance to the Differential Diagnosis of Pituitary Adenomas and RCCs

Background: Rathke’s Cleft Cysts (RCCs) are rare epithelial cysts arising from remnants of the Rathke pouch in the pituitary gland. A subset of these lesions enlarge and produce a mass effect with consequent hypopituitarism, and may result in visual loss. Moreover, some RCCs with a high intra-cystic protein content may mimic cystic pituitary adenoma, which makes their differential diagnosis ambiguous. Currently, medical professionals have no definitive way to distinguish RCCs from pituitary adenomas. Therefore, preoperative confirmation of RCCs would be of help to medical professionals for the management and proper surgical decision making. The goal of this study is to identify molecular markers in RCCs. Methods: We characterized aqueous and chloroform extracts of surgically resected RCCs and pituitary adenomas using ex vivo (1)H NMR spectroscopy. Results: All RCCs exclusively showed the presence of mucopolysaccharides which are glycosaminoglycans (GAGs) made up of disaccharides of aminosugars and uronic sugars. Conclusion: GAGs can be used as metabolite marker for the detection of RCCs and this knowledge will lay the groundwork for the development of a non-invasive, in vivo magnetic resonance spectroscopy methodology for the differential diagnosis of RCCs and pituitary adenomas using clinical MRI scanners.