A cellular glial neoplasm composed of atypical cells arranged in a disorganized pattern. The tumor demonstrates moderate to marked nuclear pleomorphism. Tumor cells have hyperchromatic and enlarged irregular nuclei. There are scattered forms with eccentric nuclei and abundant dense eosinophilic cytoplasm (gemistocytic feature). The background is fibrillary. Mitosis is active. Areas of microvascular proliferation are observed. The overall appearance is consistent with a high-grade glioma.
A large midline basilar frontal lesion, with intralesional hemorrhagic foci, restricted diffusion, and mild enhancement on post-contrast. The mass occupies the floor of the anterior cranial fossa, inseparable from the cribriform plate of the ethmoid bone. The lesion compresses and posteriorly displaces the midbrain and thalami.
Soft tissue fragments collectively measured 1.2x1x0.6 cm, totally embedded.
Midline basilar frontal lesion, biopsy: