THU102 A Case Of Papillary Craniopharyngioma WHO Grade 1 Turned Into Abscess

Disclosure: R.J. Shah: None. J. Patel: None. P.A. Belany: None. Craniopharyngioma is a rare primary brain tumor located in the suprasellar region. Papillary craniopharyngiomas (PC) occur mostly in adults, between age 40-50. Despite surgery being the primary treatment, PCs have a high tendency for relapse. We present a case of PC WHO grade 1, positive for BRAF V600E mutation concerning for regrowth 10 months following surgical resection. A 45-year-old male presented to the emergency department with complaint of right orbital headaches, vision change and severe fatigue. CT head was normal and was discharged home. Headaches, fatigue, and vision change progressively worsened over the next week with new symptoms of erectile dysfunction, low libido, weight loss, polyuria, polydipsia and proximal muscle weakness developing. Morning labs showed FT4 0.5ng/dl, TSH 2.32uIU, cortisol 1.5ug/dl, ACTH 14 pg/mL, FSH 1.5mIU/mL, LH 0.2mIU/mL, total testosterone 6ng/dl, prolactin 17.5ng/mL, IGF-1 134 ng/mL and GH 0.2ng/dl concerning for panhypopituitarism. Chemistry panel was unremarkable. MRI pituitary confirmed sellar mass measuring 2.1x1.3x2.1cm compressing the optic chiasm. Evaluated by endocrinology, patient was started on hydrocortisone, levothyroxine and desmopressin and referred to neurosurgery. Following endoscopic endonasal approach (EEA), pathology showed PC WHO Grade 1 and molecular testing positive for BRAF V600E mutation. Two-month post-surgical MRI showed residual 8mm lesion. Active surveillance showed regrowth of sellar lesion to 1.8 cm with optic chiasm compression ten months following EEA. Repeat EEA was done with concern for relapse. Surprisingly, intraoperative purulent fluid draining from the sella was found and positive for Acinetobacter. Sellar abscess was drained and he received six weeks of intravenous antibiotics. Repeat MRI showed resolution of the entire sellar lesion, his vision normalized and continued to be on hormone replacement for panhypopituitarism. PCs are locally aggressive suprasellar lesions that can reach a large size prior to clinical symptoms developing. Around 90% of PC are positive for BRAF V600 mutation. Surgical resection and radiotherapy are the primary treatment, but newer studies have demonstrated tumor regression using BRAF targeted agents following relapse. Our case demonstrates a pituitary abscess (PA) found intraoperatively that was originally suspicious for tumor recurrence. PA is a rare and serious intrasellar infection associated with high mortality. It is difficult to diagnose preoperatively and can be misdiagnosed as recurrence or residual tissue. PA can be primary or secondary depending on etiology. PA associated with residual craniopharyngioma tissue is extremely rare and the exact pathophysiology is not well understood. If no evidence of sepsis or meningitis, treatment with transsphenoidal decompression and intravenous antibiotics has good clinical outcomes. Presentation: Thursday, June 15, 2023