Encephalic fibrosarcoma in a dog.

ABSTRACT: Intracranial sarcomas are rarely reported in dogs. A 9-y-old, castrated male mixed-breed dog was evaluated and euthanized because of a 1-wk history of lethargy, dullness, disorientation, right-sided head tilt, and circling to the right. Grossly, a pale-tan, firm, 1.5-cm mass effaced ~60% of the right-ventral aspect of the pons. Histologically, the mass was composed of elongate neoplastic cells with abundant cytoplasm and round-to-oval nuclei arranged in bundles and supported by collagenous stroma. Anisocytosis and anisokaryosis were moderate, with 11 mitoses in 2.37 mm² (10 FN22/40× fields). The neoplasm was well-demarcated with occasional areas of infiltration in the surrounding neuroparenchyma. Neoplastic cells had widespread cytoplasmic immunolabeling for vimentin, patchy cyt

SUBMITTER: Crawford MJ 

PROVIDER: S-EPMC12823357 | biostudies-literature | 2026 Mar

REPOSITORIES: biostudies-literature