Communicating hydrocephalus in glioblastoma: Early predictors and implications for prognosis

Communicating hydrocephalus (CH) is a clinically relevant but often underrecognized complication in patients with glioblastoma (GBM), particularly in the setting of prolonged survival after multimodal treatment. We aimed to identify early perioperative predictors of CH requiring ventriculoperitoneal (VP) shunt placement in patients with isocitrate dehydrogenase (IDH) wild-type GBM and to assess its association with survival outcomes.

We retrospectively analyzed 120 patients treated at IRCCS San Raffaele Hospital (Milan, Italy) between 2018 and 2024. Multivariable logistic regression was used to identify independent predictors of VP shunt placement. Cox proportional hazards models were used to assess prognostic factors for overall survival (OS) and progression-free survival (PFS).

Twenty patients (16.7 %) underwent VP shunt placement after a median of 12.3 months. Intraoperative ventricular opening was the strongest independent predictor of shunt placement (OR 8.25, 95 % CI 2.23-30.49; p = 0.002). High baseline functional status (Karnofsky Performance Status ≥ 70; OR 0.16, 95 % CI 0.03-0.83; p = 0.029) and short-course radiotherapy (OR 0.04, 95 % CI 0.003-0.62; p = 0.020) were independently protective. Radiation-induced toxicity, postoperative infection, and leptomeningeal dissemination were not significantly associated with VP shunt placement. In survival analyses, ventricular opening was independently associated with longer OS (HR 0.424, 95 % CI 0.231-0.778; p = 0.006) and showed a borderline association with improved PFS.

Early perioperative factors are key determinants of communicating hydrocephalus in glioblastoma. Intraoperative ventricular opening is the main risk factor for VP shunt requirement but is independently associated with longer overall survival. These findings indicate that ventricular entry, although increasing the risk of postoperative hydrocephalus, should not discourage extensive surgical resections when required to optimize oncologic outcomes.