Integration of Neuroendoscopy in the Multidisciplinary Management of Adult Patients with Primary and Metastatic Brain Tumors

Introduction: Central nervous system tumors can obstruct cerebrospinal fluid flow, causing hydrocephalus. Endoscopic third ventriculostomy (ETV) offers a minimally invasive solution by creating an alternative CSF pathway, while also allowing for concurrent tumor biopsy. In this study, we evaluate its efficacy, safety, and potential for simultaneous diagnosis and treatment.

Methods: We prospectively identified patients with tumor-induced hydrocephalus from 2017-2024 at our institution and excluded pineal region germ cell tumors. ETV candidates presented with ventricular enlargement on imaging and/or clinical signs of hydrocephalus secondary to tumors or leptomeningeal disease.

Results: We identified 52 patients (59.6%,n=31 males; mean age 56.3 years) with tumor-induced hydrocephalus. Obstructive lesions were primarily midline, equally distributed between supratentorial and infratentorial compartments (n=26 each). Pre-ETV external ventricular drains were placed in 28.9% of patients. Concurrent procedures included tumor biopsy (25%) and septostomy (7.7%). Mean ICU stay was 2.2 days. Over a 10.4-month mean follow-up, 25% of patients required ventriculoperitoneal shunt placement due to ETV failure (mean time to failure: 71.1 days, range 10-307). Post-ETV tumor resection was necessary in 11.5% of cases (mean time: 80.8 days, range 22-160). Postoperative complication rate was 1.9%. Our analysis revealed supratentorial obstructive lesions (OR 4.79, p=0.03) and post-ETV radiation therapy (OR 4.04, p=0.046) as significant predictors of ETV failure requiring salvage shunt placement.

Conclusion : Endoscopic third ventriculostomy is an effective and safe procedure for managing tumor-induced hydrocephalus in adult patients. It offers the advantage of concurrent tumor biopsy, minimizing invasive interventions. While ETV failure occurred in 25% of cases, the low complication rate and extended time to failure suggest its viability as a first-line treatment. Supratentorial lesions and post-ETV radiation therapy were identified as risk factors for ETV failure. These findings can guide patient selection and post-operative management, potentially improving outcomes in the multidisciplinary care of brain tumor patients with hydrocephalus.