Natural history and surgical outcome of Rathke's cleft cysts—A study from the Swedish Pituitary Registry

Objective: Rathke's cleft cysts are benign, embryological remnants in the pituitary gland. The majority of them are small and asymptomatic but a few may become large, and cause mass effects, pituitary hormone deficiencies and visual impairment. Recommendations for the follow-up of Rathke's cleft cysts vary since data on the natural history are sparse. Patients and Design: Data at diagnosis and at 1, 5 and 10 years for patients with a Rathke's cleft cyst (434 at diagnosis, 317 females) were retrieved from the Swedish Pituitary Registry. Cysts ≤3 mm in diameter were excluded from the study. Measurements: Data included demographics, cyst size, pituitary function, visual defects and surgery. Results: The mean age at diagnosis was 45 years. In patients with cysts <10 mm in diameter (n = 204) 2.9% had pituitary hormone deficiencies and 2% had visual field impairments. Cyst size did not progress during the 5 years. Cysts with a diameter of ≥10 mm that were not operated (n = 174) decreased in size over the years (p <.01). Pituitary hormone deficiencies and visual impairments were more frequent (18% and 5.7%, respectively) but were stable over time. Transphenoidal surgery was performed in 56 patients of whom 51 underwent surgery before the 1-year follow-up. The mean cyst diameter at diagnosis was 18 mm (range: 9─30 mm), 36% had pituitary hormone deficiency, 45% had visual field defects and 20% had impaired visual acuity. One year after surgery 60% had no cyst remnants, 50% had a pituitary deficiency, 26% had visual field defects and 12% had impaired visual acuity. No major changes were observed after 5 years. Twelve of the operated patients had a follow-up at 10 years, in eight the cyst remnants or recurrences increased in size over time (p <.05). Conclusions: Rathke's cleft cysts with a size less than 10 mm rarely grow and our results indicate that radiological follow-up can be restricted to 5 years. In contrast, progression of postoperative remnants or recurrent cysts is more likely and require long-term follow-up.