Congenital brain tumors are exceedingly rare, typically developing during pregnancy and diagnosed either prenatally or presenting at birth or within the first weeks of life. Congenital glioblastoma (GBM) is even rarer, accounting for 3.5% of all congenital central nervous system tumors. Historically, due to its high malignant potential, the prognosis of congenital GBM has been considered poor. However, recent data suggest a better prognosis for these congenital forms compared to their pediatric and adult counterparts.

We present the case of a 15-day-old male newborn, born from a well-monitored pregnancy with unremarkable obstetric ultrasounds and a term vaginal delivery without complications, who was urgently referred due to neurological deterioration. On admission, the newborn was comatose with anisocoria and respiratory disturbances. His head circumference was >97th percentile with sutural diastasis. Brain MRI revealed a large left temporo-parieto-occipital mass measuring 7-8-9 cm, with intratumoral hemorrhage and significant midline shift. Emergency surgery was performed, revealing a hypervascular, friable, grayish lesion with intratumoral bleeding and necrotic areas. Postoperatively, the child showed no improvement and succumbed after 2 days.

A review of obstetric ultrasounds during pregnancy revealed an echogenic mass in the left cerebral hemisphere appearing at 32 weeks of gestation. Histological examination showed high tumor cell density with significant anaplastic features and extensive pseudo-palisading necrosis. Immunohistochemical analysis confirmed positivity for p53, EGFR, and GFAP, confirming the diagnosis of congenital glioblastoma.

Congenital GBM is an extremely rare tumor and can pose a neonatal neurosurgical emergency. This case underscores the importance of prenatal diagnosis to establish appropriate management based on surgery and chemotherapy.