Exploring Gliosarcoma by Light Microscopy, Two-Photon Excitation Microscopy, and Radiological Imaging Techniques

Gliosarcoma is a rare and aggressive variant of glioblastoma, characterized by both a malignant glial component and a mesenchymal sarcomatous component. Gliosarcomas have genetic alterations with glioblastomas, including TP53, PTEN mutations, and EGFR amplification, but may also exhibit additional changes related to epithelial-mesenchymal transition pathways. Management is similar to glioblastoma, involving safe, maximal surgical resection followed by radiotherapy and chemotherapy with temozolomide, but the prognosis remains poor, with a median survival of 6-14 months. Both Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) play crucial roles in the detection, characterization, and treatment planning of gliosarcoma. While MRI is the gold standard, CT remains valuable in certain situations. Light microscopy is essential for definitive diagnosis, allowing pathologists to examine cellular morphology and tissue architecture. It is essential for distinguishing gliosarcoma from other high grade gliomas and for guiding treatment decisions. In addition, two-photon excited fluorescence (TPEF) microscopy is an advanced optical imaging technique that enables real-time, high-resolution visualization of tumor tissue without the need for staining or contrast agents and enhances visualization of collagen structure and vascularization, key factors in gliosarcoma assessment. The study of radiological and histopathological (light microscopy) features in primary gliosarcomas of the brain is a priority to achieve an early diagnosis that can be translated into better outcomes. Here, we describe the radiological and histopathological features observed in multiple cases of gliosarcoma in current practice.