2025 Poster Presentations
P318: RADIOTHERAPY-RELATED FRONTAL LOBE ENCEPHALOCELE FOLLOWING ANTERIOR CRANIAL FOSSA TUMOR RESECTION: A CASE STUDY
Mariana Agudelo-Arrieta; Nayeh Arana; Alfredo Herrera; Oscar Hernando Feo-Lee; Department of Neurosurgery, Hospital Universitario San Ignacio, Pontificia Universidad Javeriana
Esthesioneuroblastoma (ENB) is a rare malignant neoplasm originating in the olfactory epithelium. Despite advances in surgical techniques and adjuvant therapies, postoperative complications can significantly impact patient outcomes.
We present the case of a 37-year-old male diagnosed with esthesioneuroblastoma, Kadish C, involving the right nasal fossa, bilateral frontal sinuses, and ethmoid cells. The patient underwent endoscopic resection of the skull base tumor with a successful initial outcome. Postoperative pathology confirmed the diagnosis, and the patient received adjuvant external beam radiotherapy using intensity-modulated radiotherapy (IMRT) to the tumor bed, totaling 6000 cGy in 200 cGy fractions over 30 sessions.
Pre-radiotherapy imaging indicated successful resection and good flap evolution. However, following radiotherapy, the patient presented with cerebrospinal fluid (CSF) leakage. MRI revealed a frontal encephalocele, likely related to radiotherapy-induced weakening of the skull base structures. This case highlights the potential late complication of radiotherapy in patients treated for sinonasal tumors, emphasizing the need for long-term monitoring.
The patient underwent endoscopic repair of the CSF fistula and encephalocele using a dural patch, fibrin sealant, and fascia lata graft. Intraoperative findings included a 3 cm anterior skull base defect with protruding frontal encephalocele, central necrosis of the nasoseptal pedicled flap, CSF leakage, and purulent secretions from the paranasal sinuses. Despite initial successful repair, the patient developed meningitis, requiring additional surgical correction of the skull base defect and CSF fistula in the anterior cranial fossa via a combined approach, alongside antibiotic management. The patient's clinical course has shown satisfactory evolution.
This case underscores the critical need for long-term surveillance in patients who undergo radiotherapy for sinonasal tumors. The development of a frontal encephalocele post-radiotherapy illustrates a significant, albeit rare, complication that can arise months or years after treatment. Recognizing the potential for such late effects is essential for timely diagnosis and intervention, which can significantly impact patient outcomes. The multidisciplinary approach, involving meticulous surgical correction and comprehensive postoperative care, highlights the importance of coordinated efforts in managing complex cases. This case emphasizes the necessity of integrating awareness of radiotherapy-related complications into routine follow-up protocols to ensure optimal long-term patient health and safety.