Peer-reviewed veterinary case report
Extranodal lymphoblastic lymphoma of suspected B-cell lineage in the gingiva of a racehorse, accompanied by mandibular osteolysis.
- Journal:
- Journal of veterinary medicine. A, Physiology, pathology, clinical medicine
- Year:
- 2003
- Authors:
- Oikawa, M et al.
- Affiliation:
- Addresses of authors: Equine Research Institute · Japan
- Species:
- horse
Plain-English summary
A thoroughbred racehorse developed a mass in its gums, which made it unable to eat on its own. Sadly, the horse was euthanized and an autopsy was performed right away. The examination revealed that the jawbone had significant damage, with very little bone left around the tooth roots. The mass was made up of abnormal cells that looked like immature lymphocytes, which are a type of white blood cell, and these cells were found to be related to B-cells, a part of the immune system. The findings suggest that the horse had a type of cancer called extranodal lymphoblastic lymphoma, likely starting in the gum area, and the damage to the bone was caused by the tumor cells affecting the bone's structure.
Abstract
A mass developed in the mandibular gingiva of a thoroughbred racehorse. When the horse could no longer eat unassisted, it was killed and immediately autopsied. Macroscopically, the mandible exhibited extensive osteolysis, with only a small amount of bone remaining around the tooth roots. The cut surface of the mass around the mandible consisted of neoplastic medullary tissue, in which osteogenesis was observed. The medullary tissue was composed of pleomorphic medium-sized to large cells, interlaced by collagen bundles. These cells had large, pale, round or ovoid, sometimes cleaved nuclei, with one or two prominent nucleoli. Mitoses were numerous. Electron microscopy showed that the cells in the medullary tissues were similar in shape to undifferentiated lymphocytes. Immunohistochemically, these cells were positive for B-cell associated antigen in the pre-B-cell stage. Our findings suggest that the horse had extranodal lymphoblastic lymphoma of suspected B-cell lineage, possibly originating from the lymphatic system of the gingiva. We consider that the osteolysis resulted from activation of osteoclasts by proliferation of the tumour cells.
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/12757553/