Peer-reviewed veterinary case report
Brain fibrosarcoma causing disorientation and head tilt in a dog
By Crawford, Megan J et al.·Published in Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc·2026·Department of Pathology, United States·View original on PubMed →
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Original publication title: Encephalic fibrosarcoma in a dog.
- Species:
- dog
Plain-English summary
A 9-year-old male mixed-breed dog was brought in after showing signs of lethargy, confusion, and a right-sided head tilt for about a week. Unfortunately, the dog was euthanized after a mass was discovered in the brain, which was identified as an encephalic fibrosarcoma (a type of brain tumor). The tumor was affecting a significant portion of the brain and showed signs of infiltration into surrounding tissue. Sadly, due to the aggressive nature of the tumor and the dog's deteriorating condition, treatment options were limited, and the decision was made to euthanize him.
People also search for: dog brain tumor symptoms · mixed-breed dog lethargy and disorientation · encephalic fibrosarcoma treatment options
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 mm(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 cytoplasmic immunolabeling for myoglobin, weak cytoplasmic immunolabeling for desmin, and rare cytoplasmic immunolabeling for myogenin. Transmission electron microscopy (TEM) revealed bundles of oval-to-elongate neoplastic cells with small-to-medium cytoplasmic aggregates of rough endoplasmic reticulum cisterns. The centrally-to-peripherally located nuclei were round and had one or more compact-to-reticulate nucleoli. Collagen bundles were in intimate contact with the plasma membrane of neoplastic cells and formed the abundant extracellular matrix. Histologic, immunohistochemical, and ultrastructural findings were consistent with an encephalic fibrosarcoma. The myogenic differentiation suggested by immunohistochemistry could not be confirmed by TEM.
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Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/41562145/