RARE-23. Preservation of endocrine function after Ommaya reservoir insertion in children with cystic craniopharyngioma

INTRODUCTION: Children with craniopharyngiomas (CP) can be subjected to significant morbidities caused by radical surgery and/or radiation with deleterious long-term consequences. Ommaya reservoir insertion (ORI) into cystic CP represents a minimally invasive procedure allowing immediate decompression and aims to avoid additional injuries. The purpose of this study was to determine the relevance of upfront ORI (+/- intracystic treatment) for preservation of endocrine function. METHODS: We performed a retrospective chart review of children with CP treated at the Hospital for Sick Children between 01/01/2000 and 15/01/2020 for review of endocrinological outcome after ORI. Endocrine function was reviewed at the time of initial surgery and throughout the course of follow-up. Event-free survival (EFS) was defined as the time to further surgical resection or irradiation. RESULTS: Seventy-nine patients were identified with a median age of 8.3 (range 2.1-18.0) years, 31 were males. Sixty-six patients underwent surgical treatment, including 41 ORI. ORI was performed as upfront treatment in 32 patients; 33 patients underwent gross total or partial resection and 1 patient radiotherapy as first treatment. Fifty-five of 79 patients had sufficient endocrine follow-up data. Endocrine function remained stable after ORI with a mean EFS of 27.64 (± 5.22) months. Surgical resection was associated with worsened endocrine function postoperatively with an EFS of 5.48 (± 1.74) months (p< 0.001). CONCLUSIONS: Upfront ORI (+/- intracystic treatment) resulted in endocrine preservation of all patients and a significantly longer EFS when compared to upfront surgical resection in this single institutional retrospective review. Further analyses will elucidate the implications of ORI with respect to ophthalmological, vascular and neurocognitive outcome.