Tumors of the lateral and third ventricles of the brain. Possibilities of endoscopic transventricular surgery. Prospects and prognosis
Authors: Palamar Orest I. , Huk Andrii P. , Teslenko Dmytro S. , Okonskyi Dmytro I. , Usatov Oleksandr S. 
Published: January 2023

Tumors of the lateral and third ventricles of the brain are uncommon in the general population. Taking into account possible disability, expected duration and quality of life of the patient in the postoperative period, radical removal of these tumors, especially invasive ones, are debatable.
Purpose: to determine the possibilities of endoscopic transventricular surgery for tumors of the lateral and third ventricles of the brain.
Materials and methods. Between 2015 and 2021, 61 patients with lateral and third ventricle tumors were treated, 9 of which were primary and 52 were invasive.All patients had a preoperative Karnofsky Performance scale score ≥70 points. Preoperative neurological status: non-focal neurological symptoms were observed in all patients, central significant hemiparesis (up to 2 points) - in 5, cognitive-mnestic disorders - in 31, opto-chiasmatic syndrome - in 2. Obstructive hydrocephalus was diagnosed in all patients. All patients underwent full-endoscopic removal by frontal transcortical transventricular approach.
Results. Total tumor resection (within healthy tissues) was performed in 34 patients, subtotal (up to 90%) – in 17, partial – in 10 patients. The postoperative condition according to Karnofsky Performance scale in all patients was ≥70 points. Hemiplegia was registered in 8 (13.1%) patients (sustained deficiency, hemiparesis (up to 3 points) - in 2 (1.22%) patients), hemianopsia - in 4 (6.5%) patients, short-term memory impairment - in 9 ( 14.75%), regression was observed 2–4 weeks after surgery. Thirty-seven (60.7%) patients died. The remaining patients (39.3%) are under observation. Median survival was 33 weeks (95% confidence interval (CI) 28–40 weeks). Postoperative survival in patients with glioblastoma was 15 weeks, median survival was 9.5 weeks (95% CI, 4–15 weeks). Of the patients with anaplastic astrocytoma, 13 (92.9%) patients died within 38 weeks after surgery, the median survival was 18 weeks (95% CI, 14.5–29.0 weeks), 1 (7.1%) patient was under observation. Patients with anaplastic oligodendroglioma had a median survival of 34.5 weeks (95% CI - 28-40 weeks), 15 (65.2%) patients died within 40 weeks, 8 (34.8%) patients are under observation. The difference between groups in survival was statistically significant (p<0.0001). Median survival in women was 34.5 weeks (95% CI, 29–40 weeks), in men, 28 weeks (95% CI, 18–39 weeks). There were 12 (42.9%) women and 12 (36.4%) men who survived for more than 60 weeks. No statistically significant difference was found between male and female survival rates (p=0.309).
Conclusions. The ability of achieving the optimal resection volume of primary and invasive tumors of the third and lateral ventricles allows recommending the anterior endoscopic transcortical transventricular approach as an effective method of surgical treatment of these tumors. Radical endoscopic resection, as the first stage of combined treatment of patients with malignant tumors of the third and lateral ventricles, increases the patients’ life expectancy with a minimal risk of postoperative neurological complications, comparable to the life expectancy of patients with malignant tumors of supratentorial localization. To eliminate obstructive hydrocephalus and prevent the obstruction of CSF circulation in case of postoperative edema or continued growth in invasive tumors of the lateral and third ventricles, it is advisable to perform triventriculocisternostomy.