MON-443 Periostin Concentrations in Childhood-Onset Craniopharyngioma Patients

Objective: The extracellular matrix protein periostin is highly expressed in adamantinomatous craniopharyngioma-associated fibroblasts. Periostin has been further identified as a novel marker for Non-Alcoholic Fatty Liver Disease (NAFLD). Half of childhood-onset craniopharyngioma patients (CP) with hypothalamic syndrome develop NAFLD. We hypothesized that periostin concentration is elevated in biological fluids of CP and associated with pathological hepatic parameters, indicating increased risk for NAFLD. Design: Cross-sectional study on patients with sellar masses (SMP) recruited in the German Craniopharyngioma Registry. Patients: 35 SMP (32 CP, 2 xanthogranuloma, one pilocytic astrocytoma), 3 short-statured patients with isolated growth hormone deficiency (GHD), 5 short-statured patients with normal findings in GH stimulating tests and decreased insulin-like growth factor (IGF)-1 (IGF-1D) and 7 healthy controls. Measurements: Periostin concentrations were measured by Elisa in serum (32 CP, 2 xanthograuloma, 3 GHD, 5 IGF-1D and 7 healthy controls), urine (27 CP, 3 GHD, 5 IGF-1D, 7 healthy controls) and saliva (18 CP, 3 GHD, 3 IGF-1D, 7 healthy controls). Results: Periostin serum, urine and saliva concentrations in CP were similar to concentrations of the other groups. Hypothalamic involvement/hypothalamic lesions, degree of obesity (BMI SDS) as well as hepatic enzymes were not associated with elevated periostin concentrations. Due to low patient numbers with pathological hepatic parameters, missing imaging data on the degree of steatosis hepatis and the lack of histological proof of NAFLD no definitive conclusions can be drawn from measured periostin concentrations in serum. Interestingly, the subgroup of patients with decreased IGF-1 levels showed elevated concentrations of serum periostin when compared with other groups. Conclusions: Periostin concentrations in biological fluids of CP are not associated with known risk factors for NAFLD such as hepatic and metabolic parameters, obesity and hypothalamic lesions. Accordingly, periostin does not seem to be a suitable marker for NAFLD in childhood-onset CP. The association between decreased IGF-1 and increased periostin concentrations should be part of further investigation.