Neuroendoscopic biopsy and the treatment of tumor-associated hydrocephalus of the ventricular and paraventricular region in pediatric patients: a nationwide study in Japan.

A neuroendoscopic biopsy is a minimally invasive and useful procedure for the diagnosis and initial management of tumor-associated hydrocephalus. We describe the nationwide investigation of the current status of neuroendoscopic biopsy for intra- and paraventricular tumors in children, as well as the treatment of tumor-associated hydrocephalus in pediatric patients. The main items examined included the patient's age and sex, location of the tumor, pathological diagnosis, complications, treatment and efficacy of treatment of the tumor-associated hydrocephalus, and the dissemination during the postoperative course. Two hundred twenty-one pediatric patients (mean 8.6 years) from 67 institutions were registered. Endoscopic tumor biopsies were performed in 206 patients (93.2 %), and a histopathological diagnosis could be performed in 195 of these 206 patients (94.7 %). The most frequently histopathologically diagnosed tumor was a germ cell tumor (41.5 %), followed by astrocytic tumors (24.1 %) and cystic lesions (15.9 %). Associated hydrocephalus was observed in 177 patients (80.1 %), 101 of whom underwent endoscopic third ventriculostomy (ETV). The efficacy rate of the ETV in the perioperative period was 99.0 %, and the long-term response rate was 90.1 %. Perioperative complications other than fever were found in 24 patients (10.9 %). In the statistical analysis, pediatric long-term response rate to ETV (p = 0.025) showed significantly more favorable results for pediatric than adult patients (p < 0.05). Neuroendoscopic procedures involving pediatric intra- and paraventricular tumors were considered to be very useful, with a low incidence of complication, and were associated with higher safety.