Peer-reviewed veterinary case report
An atypical equine gastrointestinal stromal tumor.
- Journal:
- Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc
- Year:
- 2009
- Authors:
- Muravnick, Kathleen B et al.
- Affiliation:
- Pfizer Inc.
- Species:
- horse
Plain-English summary
A 17-year-old gelded Quarter Horse cross was found to have a large mass inside its abdomen. The horse showed signs of mild colic (abdominal pain), lost weight, and had chronic anemia (low red blood cell count). During surgery, the veterinarians discovered a very large, bleeding mass attached to several parts of the intestines. Tests on the mass revealed it was a type of tumor called a gastrointestinal stromal tumor, which is unusual in horses and had some features that could have led to a misdiagnosis. The treatment involved surgery, and while the specifics of the outcome weren't detailed, the diagnosis suggests that the tumor was atypical compared to other known cases.
Abstract
A 17-year-old, gelded Quarter Horse cross was found to have a large, intra-abdominal mass. Clinical signs included infrequent mild colic, weight loss, and chronic anemia. Surgery revealed a very large, discrete, hemorrhagic, multilobular mass with vascular attachments to the transverse colon, mesocolon, jejunal mesentery, and omentum; the site of origin was the transverse colon. Histologic examination demonstrated dense sheets, fascicles, palisades, and interconnecting streams of neoplastic spindle cells with lesser numbers of admixed multinucleated giant cells. Based on morphology alone, this neoplasm might have been misdiagnosed as a peripheral nerve sheath tumor because many of the morphologic features were suggestive of neural differentiation. Neoplastic cells expressed cluster of differentiation (CD)117 (c-kit), vimentin, desmin, smooth muscle actin, neuron-specific enolase, and S-100 protein and did not express cytokeratin. Based predominantly on the immunohistochemical profile, especially the CD117 positivity, this neoplasm was diagnosed as a gastrointestinal stromal tumor with both myogenic and neurogenic differentiation. The morphology and immunohistochemical profile of this neoplasm were different from published cases of equine gastrointestinal stromal tumors. Unusual aspects included the large size of this neoplasm, the neuroid rather than myxomatous morphology, the presence of multinucleated giant cells, and the expression of desmin.
Find similar cases for your pet
PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.
Search related cases →Original publication: https://pubmed.ncbi.nlm.nih.gov/19407097/