Radiological Findings in Gliosarcoma: A Diagnostic Challenge

Aim: This study aims to identify the primary differential MRI features between gliosarcoma (GS) and glioblastoma (GBM) based on a comprehensive review of existing literature. Given their close relationship, identifying preoperative neuroradiological markers is essential for distinguishing these two entities. Methods and Analysis: We reviewed studies involving patients with histologically confirmed GS and primary GBM. Our analysis, aligned with the 2021 WHO Classification of Tumors of the Central Nervous System, evaluated specific radiological characteristics in order to determine their diagnostic value in differential diagnosis. Results: While GS is categorized as a variant of GBM, distinct radiological patterns emerged from our literature review. Gliosarcomas are typically larger due to their sarcomatous component and exhibit more intense contrast enhancement and frequent cortical involvement. Notably, hemorrhagic patterns are more prevalent in GS, whereas GS displays less necrosis and a lower incidence of midline-crossing edema compared to GBM. Conversely, glioblastomas more frequently present with cystic components and pial involvements as well as a higher risk of ependymal invasion. Conclusions: Although specific radiological features—such as hemorrhage frequency and tumor size—can strongly suggest GS over GBM diagnosis, no single feature was considered pathognomonic. Among radiological tools, MRI remains the most important for guiding a diagnostic suspicion, but histopathological confirmation remains the gold standard for definitive diagnosis.