Spontaneous Near-Resolution of a Rathke’s Cleft Cyst

Abstract

•Spontaneous near resolution of Rathke’s cleft cyst can occur•Conservative approach is recommended in the absence of mass effect or visual disturbance•The mechanism of spontaneous near resolution of RCC is poorly understood A 70-year-old Caucasian woman with history of chronic sinusitis presented to the Emergency department with 2-week history of headaches. Her physical examination was unremarkable including absence of galactorrhea, abnormal hair growth, or skin changes. Neurologic exam including visual fields were normal. Brain MRI revealed a 1.2 x 1.4x 1.3 cm ovoid, non-enhancing, cyst-like lesion with intrasellar and suprasellar components (Figure 1) with slight elevation and splaying of the optic chiasm and depression of the sella floor. Hormonal testing revealed normal values (Table 1). A conservative approach was chosen given the patient’s age, the lesion size, and lack of visual compromise or hormonal dysfunction.Table 1HormoneResultNormal RangeTSH0.90.280 – 3.980 ng/dlFree T40.600.58-1.64 ng/dlIGF-13741-279 ng/mlGrowth Hormone0.9<7.1 ng/mlProlactin19.272.74-19.64 ng/mLCortisol16.67-9a.m 4.0-22.0 mcg/dl Open table in a new tab At 1 month follow up she denied new symptoms. Repeat hormonal panel revealed a low FT4 0.5, and normal TSH 3.93, which prompted initiation of levothyroxine. The rest of the panel remained normal. A follow-up brain MRI revealed a hypoenhancing lesion within the sella with suprasellar extension measuring 1.1x 1.3 x0.9 cm (figure 2), contacting the optic chiasm without displacement. Ophthalmology evaluation reported normal visual fields. Neurosurgery recommended medical management. A year after initial presentation, TSH and Ft4 were normal on levothyroxine. Brain MRI revealed complete resolution of the previously characterized cystic lesion, with a normal-sized and shaped pituitary gland (figure 3). Patient continued to have intermittent headaches that were attributed to chronic sinusitis. The patient has not returned for a follow up visit, and we have been unable to reassess her pituitary/thyroid axis. What is the diagnosis? Answer: The clinical course and imaging findings are best explained by a rare case of a Rathke’s Cleft Cyst (RCC), with near spontaneous resolution. RCC are remnants of a failed regression of the developmental ectodermal pouch, characterized by unpredictable natural histories that can include spontaneous enlargement or less commonly decrease in size. The latter has been observed in up to 15% in studies evaluating the evolution and volumetry analysis of RCC (1Barkhoudarian G. Palejwala S.K. Ansari S. Eisenberg A.A. Huang X. Griffiths C.F. et al.Rathke’s cleft cysts: a 6-year experience of surgery vs. observation with comparative volumetric analysis.Pituitary [Internet]. 2019; 22 (Available from:): 362-371https://doi.org/10.1007/s11102-019-00962-yCrossref PubMed Scopus (19) Google Scholar). Symptoms may include headaches, pituitary dysfunction, and visual deficits from mass effect (2Altuwaijri N, Cote DJ, Lamba N, Albenayan W, Ren SP, Zaghloul I, et al. Headache Resolution After Rathke Cleft Cyst Resection: A Meta-Analysis. World Neurosurg [Internet]. 2018;111:e764–72. Available from: https://doi.org/10.1016/j.wneu.2017.12.170Google Scholar). There are no standardized management guidelines, however a conservative approach is preferred when there is absence of mass effect or visual disturbance as seen here(3Truong L.U.F. Bazin C. Gomis P. Decoudier B. Delemer B. Litré C.F. Surgery versus conservative care for Rathke’s cleft cyst.Neurochirurgie. 2021; 67: 104-111Crossref PubMed Scopus (4) Google Scholar). The mechanism of spontaneous resolution of RCC is poorly understood. This is a rare case of spontaneous near resolution of RCC in a patient that was followed by conservative therapy with regular clinical and radiologic follow up.