Rathke's cleft cyst: From history to molecular genetics

A Rathke's cleft cyst (RCC) is a remnant of the embryologic Rathke's pouch and a common pituitary lesion. A true RCC is lined with ciliated cuboidal or columnar epithelia with occasional goblet cells and squamous metaplasia. A RCC is frequently diagnosed incidentally through magnetic resonance imaging and computed tomography of the brain or pituitary gland. Presentation can range from an asymptomatic clinical picture to a rapidly progressive disease. RCC are located most often in the sellar and suprasellar regions and a careful differential diagnosis is crucial, especially to exclude craniophryngioma. Recent studies illuminate novel molecular mechanisms and markers for understanding the pathogenesis of RCC. PROP-1, a paired-like homeodomain transcription factor, controls pituitary ontogeny and its high expression induces RCCs. Both transgenic mouse models and immunohistochemical analysis of human RCCs indicate that the leukemia inhibitory factor is involved in pathogenesis. The expression of cytokeratins 8 and 2 in RCCs, but not in craniopharyngiomas, and the presence of beta-catenin mutations in many craniopharyngiomas, but not in RCCs, help with the differential diagnosis. For asymptomatic and small RCCs, observation is appropriate, with serial magnetic resonance imaging and hormonal investigation depending on the patient's clinical status. Surgical resection may be required for symptomatic RCC and recurrence rates are generally low. For patients with a recurrence, stereotactic radiosurgery is an effective approach with low risk.

Surgical management of symptomatic recurrent Rathke's cleft cysts: A systematic review and individual-participant data meta-analysis

The optimal management of symptomatic recurrent Rathke's cleft cysts (RCCs) is unclear. Here, we compared the outcomes of various surgical approaches for symptomatic recurrent RCCs. PubMed and Embase were systematically reviewed for studies that reported individual-participant data on outcomes after surgical treatment for symptomatic recurrent RCCs presenting with headache and/or visual field defect. The primary outcome was symptomatic recurrence, and the secondary outcome was postoperative complications. Subgroup analyses were performed based on the number of recurrences, duration since initial surgery, previous treatment, and symptoms of recurrence. Of the 713 studies screened, 14 studies (30 recurrences in 24 patients) were included in the meta-analysis. Cyst wall resection was the most common treatment (n = 17, 56.7 %), followed by drainage with intrasellar stent insertion (n = 7, 23.3 %) and resection with intracystic bleomycin (n = 6, 20.0 %). Most of the cases were first recurrences (56.7 %, n = 17). The mean (SD) duration between the initial treatment and onset of symptomatic recurrence was 3.0 (3.6) years. Over a median [IQR] follow-up period of 1.2 [0.4, 2.5] years, patients who underwent cyst wall resection had a significantly higher incidence of symptomatic recurrence at 58.8 %, compared to a 0 % symptomatic recurrence rate in patients treated with drainage and intrasellar stent insertion or resection with intracystic bleomycin (p = 0.014). Patients who underwent cyst wall resection also had the highest risk of symptomatic recurrence on subgroup analysis, though this was statistically significant only among patients who underwent cyst wall resection as their preceding treatment (p = 0.021). There were no significant differences in postoperative complication rates between the treatment arms. In conclusion, for patients with symptomatic recurrent RCCs presenting with headache and/or visual field defects, drainage with intrasellar stent insertion and intracystic bleomycin may be superior to cyst wall resection alone. This approach may reduce the risk of another symptomatic recurrence within one year.

Endoscopic Treatment of Rathke’s Cleft Cysts: The Case for Simple Fenestration

Background: Rathke’s cleft cysts (RCC) arise from the pars intermedia because of incomplete regression of the embryologic Rathke pouch. A subset of RCC becomes symptomatic causing headaches, visual and endocrinological disturbances such that surgical intervention is indicated. Several points in surgical management remain controversial including operative strategy (simple fenestration (SF) vs complete cyst wall resection (CWR)) as well as reconstructive techniques. Methods: A retrospective analysis was conducted of pathologically confirmed RCC operated on by endoscopic endonasal approach from 2006 to 2019. Pre-operative symptoms, imaging characteristics, operative strategy, symptom response, complications and recurrences were recorded. Results: Thirty-nine patients were identified. Thirty-three underwent SF and six underwent CWR. Worsening pituitary function was significantly increased with CWR (50%) compared to SF (3%) (p = 0.008). All patients underwent “closed” reconstruction with a post-operative CSF leak rate of 5% (3% SF vs 16% CWR, p = 0.287). Six (15%) recurrences necessitating surgery were reported. Recurrence rates stratified by surgical technique (18% SF vs 0% CWR, p = 0.564) were not found to be significantly different. Conclusions: The current series illustrates variability in the surgical management of RCCs. SF with closed reconstruction is a reasonable operative strategy for most symptomatic RCCs cases while CWR can be reserved for selected cases.

Stereotactic radiosurgery for Rathke's cleft cysts: an international multicenter study

OBJECTIVE

Rathke's cleft cysts (RCCs) are sellar collections from an incompletely regressed Rathke's pouch. Common symptoms of RCCs can include headaches, visual loss, and endocrinopathy. Surgery is required in some cases of symptomatic or growing RCCs. Recurrence after surgery is common (range 10%-40%). Stereotactic radiosurgery (SRS) has been used in an attempt to control growth and symptoms, but outcomes are not well known. The authors sought to study the outcomes of RCCs following Gamma Knife surgery for both salvage and initial treatment.

METHODS

The outcomes of 25 patients with RCCs who underwent SRS between 2001 and 2020 were reviewed. Four patients received initial 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 (76%) of 25 patients, and 4 recurrences required further intervention. The average time to recurrence was 35.6 months in those RCCs that recurred. Visual recovery occurred in 14 (93.3%) of 15 patients and no new post-SRS visual deficits occurred. The presence of a pretreatment visual deficit was often an indicator of RCC regrowth. All 3 patients with pretreatment hyperprolactinemia experienced resolution after SRS. New endocrinopathy related to SRS was noted in 5 (20%) of 25 patients, all of which were thyroid and/or cortisol axis related. Upfront SRS was used in 4 patients. No new endocrinopathies or visual deficits developed after upfront SRS, and the 1 patient with a pretreatment visual deficit recovered. One of the 4 patients with upfront SRS experienced a recurrence after 7.5 years.

CONCLUSIONS

SRS produced effective recovery of visual deficits and carries a low risk for new visual deficits. Cyst control was achieved in approximately three-fourths of the patients. Following SRS, patients without pretreatment visual deficits are less likely to have RCC regrowth. Endocrinopathy can occur after SRS, similar to other sellar mass lesions. Initial SRS shows the potential for long-term cyst control, with improvement of symptoms and a low risk for complications.

A clinical approach to parasellar lesions in the transition age

Many reviews have summarised the pathology and management of the parasellar region in adult patients, although an analysis of these aspects in the transition years, from puberty onset to the age of peak bone mass, has been lacking. A comprehensive search of English-language original articles, published from 2000 to 2020, was conducted in the MEDLINE database (December 2019 to March 2020). We selected all studies regarding epidemiology, diagnosis and management of the following parasellar lesions: germinoma, craniopharyngioma, Langerhans cell histiocytosis, optic glioma, hypothalamic hamartoma, tuber cinereum hamartoma, cranial chordoma, Rathke cleft cyst, hypophysitis and hypothalamitis during the transition age from childhood to adulthood. In the present review, we provide an overview of the principal parasellar lesions occurring in the transition age. Symptoms are usually a result of the mass effect of the lesions on nearby structures, as well as anterior pituitary deficits. Diabetes insipidus occurs frequently in these patients. In this age group, pubertal developmental disorders may be more evident compared to other stages of life. Parasellar lesions in the transition age mostly include neoplastic lesions such as germinomas, hamartomas, optic gliomas, craniopharyngiomas Langerhans cell histiocytosis and chordomas, and rarely inflammatory lesions (hypophysitis, hypothalamitis). There are limited data on the management of parasellar lesions in the transition age. Endocrine evaluation is crucial for identifying conditions that require hormonal treatment so that they can be treated early to improve the quality of life of the individual patient in this complex age range. The clinical approach to parasellar lesions involves a multidisciplinary effort.