SAT-105 The Natural History of Pituitary Cysts in Patients with Growth Hormone Deficiency and Idiopathic Short Stature

Background: The sequential follow-up of simple fluid-filled pituitary cysts (PC) has not been fully elucidated. In this study, we further report our follow up of PCs in a cohort of pediatric patients (PTs). Objective: To further analyze the sequential cyst volume (CV) change in short children. Patients and Methods: A pediatric endocrinology and neuroradiology center was queried for the presence of PCs. PTs who underwent multiple high resolution post-contrast MRIs (1mm slices) were subjects of this study. PTs with additional MRI abnormalities were excluded. Pituitary volumes (PV) and CVs were measured using the ellipsoid formula (LxWxH/2). The percentage of the gland occupied by the cyst (POGO) was measured and calculated. A cyst with a POGO ≤15% was defined as a small pituitary cyst (SPC), and a POGO >15% was defined as a large pituitary cyst (LPC). 34 PTs met inclusion criteria, all of whom were diagnosed with short stature (23 growth hormone deficient (GHD) PTs and 11 idiopathic short stature (ISS) PTs). All PTs were receiving GH during data collection. Results: The mean (MN) and median (MD) ages for these subjects were 10.7 yrs ±3.5 and 11.1 yrs, respectively (RSP). Of the 34 PTs, 24 PTs’ (71%) initial MRI demonstrated a SPC and 10 PTs’ (29%) initial MRI demonstrated a LPC. The MN and MD times between first and second MRIs were 1.23 yrs and 0.83 yrs RSP, with a range (RG) of 0.14 to 4.08 yrs. The MN and MD ΔCV for all PTs was 23.33% ±179.17% and -25.94% RSP, with a RG of -100.00% to 763.94%. The MN and MD ΔPOGO by the cyst for all PTs was 48.59% ±313.26% and -36.84% RSP, with a RG of -100.00% to 1734.79%. The MN and MD ΔCV for PTs with a SPC was 10.68% ±2.65% and 11.09% RSP, with a RG of -100.00% to 763.94%. The MN and MD ΔPOGO by the cyst for PTs with a SPC was 78.33% ±369.96% and -31.34% RSP, with a RG of -100.00% to 1734.79%. The MN and MD ΔCV for PTs with a LPC was -24.60% ±51.89% and -26.57% RSP, with a RG of -88.57% to 91.38%. The MN and MD ΔPOGO by the cyst for PTs with a LPC was -22.79% ±44.90% and -40.46% RSP, with a RG of -80.95% to 47.11%. Statistical analysis showed no significant %ΔCV or %ΔPOGO when comparing male vs. female, SPC vs. LPC, GHD vs. ISS, or pre-pubertal vs. pubertal PTs. Analysis of ΔPOGO of the 24 SPC PTs demonstrated that 4 (17%) of them developed into LPCs. Analysis of the 10 LPC PTs showed that 6 (60%) of them shrunk into SPCs, one of which re-enlarged into a LPC, and another of which fluctuated between LPC and SPC over a period of 7.34 yrs and 9 sequential MRIs. None of the PTs experienced significant sequelae related to their PCs. Conclusion: CV can change greatly over time, however few sequelae should be expected. LPCs tend to demonstrate major changes in size and should be tracked for CV change. A minority of SPCs will develop into LPCs. Prediction of change in CV over time requires more sequential data. Change in CV did not appear to be influenced by GH therapy.

The prevalence and volumetry of pituitary cysts in children with growth hormone deficiency and idiopathic short stature

BackgroundPituitary cysts have been speculated to cause endocrinopathies. We sought to describe the prevalence and volumetry of pituitary cysts in patients with growth hormone deficiency (GHD) and idiopathic short stature (ISS).MethodsSix hundred and eighteen children evaluated for growth failure at the Division of Pediatric Endocrinology at New York Medical College between the years 2002 and 2012, who underwent GH stimulation testing and had a brain magnetic resonance imaging (MRI) prior to initiating GH treatment were randomly selected to be a part of this study. High resolution MRI was used to evaluate the pituitary gland for size and the presence of a cyst. Cyst prevalence, cyst volume and percentage of the gland occupied by the cyst (POGO) were documented.ResultsFifty-six patients had a cyst, giving an overall prevalence of 9.1%. The prevalence of cysts in GHD patients compared to ISS patients was not significant (13.5% vs. 5.7%, p=0.46). Mean cyst volume was greater in GHD patients than ISS patients (62.0 mm3vs. 29.4 mm3, p=0.01). POGO for GHD patients was significantly greater (p=0.003) than for ISS patients (15.3%±12.8 vs. 7.1%±8.0). Observers were blinded to patient groups.ConclusionsGHD patients had a significantly greater volume and POGO compared to ISS patients. This raises the question of whether cysts are implicated in the pathology of growth failure.