Case Report: Differential diagnosis of Rathke’s cleft cyst and sellar xanthogranuloma by 1H magnetic resonance spectroscopy
Year: 2026
Type: article
Abstract: Background Sellar xanthogranulomas closely resemble Rathke’s cleft cysts (RCCs) and present a diagnostic challenge. It is difficult to differentiate xanthogranulomas preoperatively from other sellar masses, such as RCCs. The objective of this study is to differentiate the biochemical profiles of xanthogranulomas and RCCs using ex vivo 1 H magnetic resonance spectroscopy (MRS), which may serve as a valuable future tool for the non-invasive diagnosis of sellar lesions. Case presentation A 48-year-old man presented with an episode of numbness and tingling in the legs, followed by severe malaise and weakness (September 2021). The initial blood work revealed hyponatremia (serum sodium, 127 mmol/L). A detailed blood hormone panel revealed hypocortisolism (blood cortisol, <1.0 µg/dL). Magnetic resonance imaging (MRI) examination of the brain and pituitary region detected 2.0 cm × 1.7 cm × 1.7 cm sellar/suprasellar mass that was predominantly hyperintense on pre-contrast T1- and T2-weighted images, and a diagnosis of subacute pituitary apoplexy or complex RCC was made. Prior to presentation to our center, the patient was diagnosed with hypothyroidism. To treat the above conditions, the patient was placed on hydrocortisone (30 mg/day) fludrocortisone (0.1 mg/day) and levothyroxine (88 µg/day) replacement therapy (October 2021) before transfer to our care. The patient underwent endoscopic transsphenoidal exploration and selective removal of the sellar mass (November 2021). Biochemical analysis of the resected specimen by ex vivo 1 H magnetic resonance spectroscopy ( 1 H MRS) revealed the absence of glycosaminoglycans (GAGs) and showed the elevated levels of lactate (9.0 mM), when compared to biochemical profile of RCC specimen. The increased lactate levels in xanthogranuloma indicate ongoing inflammatory processes within the sellar lesion. Additionally, lipid profiling of xanthogranuloma showed elevated levels of cholesterol and cholesteryl esters. Surgical pathology of the sellar lesion demonstrated xanthogranulomatous reactions with chronic inflammation, the presence of cholesterol clefts and necrosis, findings that are consistent with 1 H MRS findings. Conclusion Although sellar xanthogranulomas may resemble RCCs histologically, they exhibit distinct biochemical and lipidomic profiles characterized by the absence of GAGs and elevated levels of lactate, cholesterol and cholesteryl esters. 1 H MRS has potential to differentiate the biochemical profiles of xanthogranulomas and RCCs. Furthermore, the findings from this study may be translated into non-invasive diagnostic methods using clinical MRI scanners, enabling improved preoperative differentiation of sellar lesions.
Source: Frontiers in Endocrinology
Language: English
Subfield: Endocrinology, Diabetes and Metabolism
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W7225648255