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.
Objective: The study subject approaches a topic of cerebral pathology, namely the development of a pathological diagnosis that is as accurate as possible for the cerebral tumors and the metastases, using a new method that complements the optical microscopic examination and immunohistochemistry to correctly diagnose cerebral malignancies. Methods: Two-photon excitation (TPE) microscopy techniques are non-linear optical imaging methods that are gaining momentum in the investigation of fixed tissue sections, fresh tissue, or even for in vivo experiments. This method can be used for offering complementary information on the tissue architecture. We argue that using non-linear optical microscopy (which includes TPE microscopy) images collected on this category of brain tissue samples, can facilitate the interpretation of brain tumors and metastases, thus it is a solution worthy to explore. Scanning large areas of the lesions is important to avoid false-negative diagnoses because lesions are often non-uniform. Finding potential invasion sites is also restricted when using a narrow field-of-view imaging method. Results: Our study demonstrated that TPE microscopy can detect specific cellular features of cerebral tumors and metastases in good correlation with histopathological results. This approach can improve the accuracy of the cerebral tumors diagnosis and possibly other neoplasms. Conclusion: TPE microscopy is very important for future research because it could prevent the false or inadequate diagnosis of specific lesions and differentiate a primary tumor from a metastasis. The significance of the findings is attributable to cross-disciplinary cooperation and the constant use of a working standard across all of the experiments in this study.
