Cp-14. Volumetric Analysis of Paediatric Craniopharyngiomas: Clinical-Radiological Correlation Study

Abstract BACKGROUND Craniopharyngioma are heterogeneous hypothalamopituitary tumours with solid and cystic components which have a distinct natural history. Neuroimaging follow-up and the definition of progressive disease is challenging due to unpredictable growth of the inflammatory cystic component. METHODS This multicentre retrospective observational study aimed to describe the clinical-radiological correlation of craniopharyngiomas at two paediatric neurosurgery units (GOSH,UK and USP,Brazil). Craniopharyngiomas treated over a 20-year period were identified and standardized clinical outcomes recorded. Baseline MRIs were reviewed and volumetric T1-weighted images segmented by a board-certified paediatric neuroradiologist. RESULTS Of 123 patients, 92 baseline MRIs were available for image analysis (USP=32; GOSH=60). No differences between series were identified in either demography (mean age: USP=9.2±4.6; GOSH=8.2±4.1 years) or tumour characteristics, with tumours being predominantly cystic (USP=75%; GOSH=76%), localised to the sellar/suprasellar region (USP=84%; GOSH: 88%), and on pre-chiasmatic (USP=34%; GOSH=22%) or retro-chiasmatic (USP=59%; GOSH=67%) locations. Pre-chiasmatic tumours were associated with an increased prevalence of visual symptoms at presentation (p=0.006) and worse recovery of visual acuity at long-term follow-up (p=0.021). Regarding volumetric analysis, mean volumes were 16.6±25.1cm3 for the cystic component and 38.3±10cm3 for the solid component. Volumes of the solid and cystic components had no correlation with each other. Larger cystic tumour volumes were correlated with a greater prevalence of diabetes insipidus at presentation (p=0.06). Larger solid tumours were significantly related to younger ages (p=0.02) and had worse PFS in our series. In terms of long-term outcomes, high volume cystic tumours were related to worse hypothalamic outcomes. In multivariate analysis (n=92), Paris classification did not predict long-term outcomes. CONCLUSIONS Volumetric analysis of craniopharyngiomas showed significant correlation with the onset of diabetes insipidus and hypothalamic long-term outcomes. Larger cystic craniopharyngioma were more common in younger patients. The Paris classification did not predict long-term outcomes in multivariate analysis.