Natural history and surgical outcome of Rathkes cleft cysts - A study from the Swedish Pituitary Registry

Objective Rathkes 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 Rathkes 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 Rathkes 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: 930 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 Rathkes 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