Lymphosarcoma with urinary bladder infiltration in a horse.

The study discusses a case of a 9-year-old Thoroughbred mare suffering from lymphosarcoma, a cancerous condition affecting the lymphatic system, which has also infiltrated the urinary bladder, leading to health symptoms like frequent urination, blood in the urine, and weight loss.

Case Background and Manifestations

• The mare was presented with symptoms of frequent urination (pollakiuria), blood in the urine (hematuria), and weight loss, which had developed over a period of three weeks.
• In addition to these symptoms, the physical examination exhibited a normal but periodically irregular heartbeat and a soft tissue mass discoverable in the pelvic canal through rectal examination.

Laboratory Findings

• Through a microscopic examination of urine sediment, a substantial number of red blood cells and an unusually large population of lymphocytes and lymphoblasts displaying neoplastic traits were found.
• Peritoneal fluid, procured through an abdominocentesis, revealed the presence of similar cells.

Treatment and Findings Post-Mortem

• The mare, unfortunately, was euthanized without any treatment. The decision for euthanization often depends on a variety of factors including but not limited to the severity of the condition, quality of life, and potential recovery or lifespan with treatment.
• Upon post-mortem examination (necropsy), it was found that the soft tissue mass originally detected had infiltrated not only the bladder but had extended to the vagina, and uterus as well.
• Additional growths were also noticed in the sublumbar muscles and myocardium, otherwise known as heart muscle tissue.

Diagnosis

• Based on all the physical, clinical and laboratory findings, along with necropsy results, the final histologic diagnosis confirmed the presence of lymphosarcoma, a type of cancer that affects the lymphatic system.

This research improves our understanding of the presentation and possible systemic involvement of lymphosarcoma in horses, which can help in early detection and management of the disease in veterinary practice.