Primary dissemination of high-grade gliomas in children: experiences from four studies of the Pediatric Oncology and Hematology Society of the German Language Group (GPOH)

Purpose. Clinical data on central nervous system (CNS) dissemination of high-grade gliomas (HGG) at initial presentation in children are rare. Patients and methods. We conducted a retrospective data analysis of all patients enrolled into four consecutive HGG protocols of the Pediatric Oncology and Hematology Society of the German Language Group (GPOH) to determine the incidence of primary CNS dissemination of HGG and to describe clinical characteristics and outcome of children with HGG who were diagnosed with CNS dissemination at initial presentation. 546 patients with newly diagnosed HGG (n=348) or diffuse intrinsic pontine gliomas (n=198) were enrolled in these four studies. Data concerning tumor dissemination are available from 324 patients. Results. A total of 10 patients (3.1%) (anaplastic astrocytoma: n=3, glioblastoma multiforme: n=6, diffuse intrinsic pontine glioma: n=1) had primary tumor dissemination. Median age at diagnosis was 9.3 years (range: 0.3-21.3 years). The most frequent primary tumor sites were the cortex (n=4), followed by the ventricles (n=2), cerebellum (n=1), spinal cord (n=1), and pons (n=1). One patient had diffuse gliomatosis cerebri. Following surgery eight patients received local radiotherapy and eight additional chemotherapy. At a median follow-up of 10 months (range: 0.05-3 years) four patients are alive. None is disease-free. Median progression-free and overall survival was 0.8 years (95% CI 0.2-1.4) and 1.5 years (95% CI 0.67-2.29) for patients with primary tumor dissemination, respectively, with no statistically significant differences between the group with and the group without primary tumor dissemination. Conclusions. Initial diagnostic evaluation should include complete CNS imaging as well as cerebrospinal fluid examination in all patients with HGG. As prognosis of children with HGG and primary CNS dissemination was not inferior to patients without dissemination in our population, these patients should be treated in the same way as patients without primary CNS dissemination.