Gastric leiomyosarcoma in a horse.

This research article discusses a case report of a 12-year-old Thoroughbred horse who was diagnosed with a form of stomach cancer called gastric leiomyosarcoma after displaying symptoms of anorexia, weight loss, and intermittent fevers over a period of 1.5 months.

Summary of findings

• The horse was investigated due to a variety of concerning symptoms including loss of appetite (anorexia), unexplained weight loss, and intermittent bouts of fever over a duration of 1.5 months. Initial testing was extensive but did not lead to a conclusive diagnosis using noninvasive methods.
• An exploratory celiotomy (surgical incision into the abdominal cavity) was performed which revealed an intra-abdominal mass. Due to the severity and progression of the disease, the horse was euthanized.
• Postmortem examination, or necropsy, revealed a firm mass connected to the end of the esophagus, the upper two-thirds of the stomach, and the visceral surface of the liver.
• The mass was examined histologically (using a microscope to examine tissue structure) and was diagnosed as leiomyosarcoma, a rare, malignant (cancerous) tumor that affects smooth muscle tissue.

Context and Implications

• Gastric leiomyosarcoma is a rare form of cancer most often found in the stomach or intestines, and is quite rare in horses. This case provides valuable insight into the presentation, diagnosis, and location of gastric leiomyosarcoma in horses.
• This research report emphasizes the importance of early diagnostic screening and the limitations of noninvasive diagnostic approaches in veterinary practice. As in this case, the conclusive diagnosis was reached only after surgical exploration and subsequent microscopic examination of the mass.
• This report also contributes to the veterinary literature by documenting a case of leiomyosarcoma in a thoroughbred horse, contributing to our understanding of the disease’s prevalence in different species and breeds.

Potential future research

• Because leiomyosarcoma is rare in horses, there is potential for further research in understanding risk factors and potential preventive measures among the breed.
• A better understanding of this disease’s pathologies will allow for improved diagnostic accuracy and potentially help formulate effective treatment plans in the future.