HGG-43. CONGENITAL GLIOBLASTOMA MULTIFORME: A CASE REPORT OF A RARE PEDIATRIC BRAIN TUMOR, MOLECULAR ANALYSIS, AND REVIEW OF THE LITERATURE

Congenital brain tumors are rare, accounting for less than 4% of all pediatric brain tumors. Congenital glioblastoma multiforme (GBM) is rarer still, accounting for 3–15% of congenital brain tumors. There is literature to suggest that these tumors differ from pediatric and adult GBM clinically and molecularly, and as such should be treated as their own distinct entity. Our case is a 4 week old male who initially presented to his pediatrician for enlarging head circumference and upward gaze palsy. An MRI was obtained revealing a right parietal mass. He underwent gross total resection the following day with pathology revealing glioblastoma, WHO grade IV. Further analysis revealed ATRX retained, p53 immunoreactivity in 15–20% of nuclei, IDH1 and IDH2 wildtype, MGMT promoter not methylated, H3K27M wildtype, no 1p and/or 19q deletion/codeletion. Interestingly, RNA analysis of his tumor detected the PPP1CB-ALK fusion transcript as well as amplification of the ALK gene. Co-occurrence of these mutations has been reported in a small number of pediatric glioblastoma patients and PPP1CB-ALK fusions are one of the most common receptor tyrosine kinase fusions in infantile gliomas. ALK rearrangements and amplifications suggest a potential therapeutic target with tyrosine kinase inhibitors in glioblastoma. This patient serves as an example of a rare congenital glioblastoma with unique molecular features that may suggest novel treatment opportunities. We present his clinical course along with a pertinent review of the literature.

Congenital Gliosarcoma: Detailed Clinicopathologic Documentation of a Rare Neoplasm

Congenital brain tumors are rare. Clinically, they often result in macrocrania, hydrocephalus, and focal neurologic deficits. Fetal onset may result in dystocia and stillbirth. Antenatal detection is becoming more common as the result of neuroimaging, and modalities such as magnetic resonance imaging can assist in narrowing the pathologic differential diagnoses. Teratomas and astrocytomas appear to be the most common congenital neoplasms. Amongst the latter, all grades and many subtypes are represented in the congenital time period, including the diffusely infiltrative forms of astrocytoma. Gliosarcoma is currently considered a variant of glioblastoma (i.e., astrocytoma, World Health Organization grade IV) that exhibits genetically similar yet phenotypically separate histologic regions of high-grade astrocytoma and sarcoma. Only rare instances of congenital gliosarcoma have been reported. We detail the case of a 1-day-old term male who presented with macrocrania, hydrocephalus, and signs of increased intracranial pressure. Pathology revealed evidence of a classic gliosarcoma.