Stereotactic Radiosurgery for Rathke’s Cleft Cysts: An International Multicenter Study.

Objective: Rathke’s cleft cysts (RCC) are sellar collections from an incompletely regressed Rathke’s pouch. Common symptoms can include headaches, visual loss, and endocrinopathy. In some cases of symptomatic or growing RCC, surgery is required. Recurrence after surgery is common (10-40%). Stereotactic radiosurgery (SRS) has been used in an attempt to control growth and symptoms, but outcomes are not well known. We sought to study the outcomes of Rathke’s cleft cysts following Gamma Knife radiosurgery for both salvage and initial treatment. Methods: We reviewed the outcomes of 25 Rathke’s cleft cyst patients that had stereotactic radiosurgery between 2001 and 2020. Four patients received upfront SRS, and 21 were treated with salvage SRS. Diagnosis was based on imaging or histopathology. Cyst control was defined as stability or regression of the cyst. Kaplan-Meier analysis was used to determine time-to-recurrence and determine potential factors for recurrence. Results: The respective median clinical follow-up and margin dose were 6.5 years and 12 Gy. Overall control was achieved in 19/25 (76%) patients, and four recurrences required further intervention. For those that recurred, the average time to recurrence was 35.6 months. Visual recovery occurred in 14/15 (93.3%) patients, and no new post-radiosurgery visual deficits occurred. The presence of pre-treatment visual deficit was often an indicator of regrowth. 3 of 3 patients with hyperprolactinemia resolved after SRS. New endocrinopathy related to radiosurgery was noted in 5/25 (20%) patients, all of which were thyroid and/ or cortisol axis related. Upfront SRS was used in four patients. No new endocrinopathies or visual deficits developed after upfront SRS, and the single patient with a pretreatment visual deficit recovered. One of the four upfront SRS patients recurred, after 7.5 years. Conclusion: Stereotactic radiosurgery produced effective recovery of visual deficits, and carries a low risk for new visual deficits. Cyst control was achieved in about three quarters of the patients. Following radiosurgery, patients without pre-treatment visual deficits are less likely to regrow. Endocrinopathy can occur after radiosurgery, similar to other sellar mass lesions. Initial radiosurgery shows the potential for long-term cyst control, with improvement of symptoms and low risk for complications. [ABSTRACT FROM AUTHOR]