فرزاد حیاتی - Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad,Iran.
انسیه سجادیان جاغرق - Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Iran
محسن ملکی - Department of Pathobiology, Faculty of veterinary medicine, Ferdowsi University of Mashhad, Mashhad,Iran.
مهدی حسنخانی - Department of Small Animal Clinical Sciences, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
حسین خوری باب الحکم - Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad,Mashhad, Iran
فاطمه نمازی - Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.

    A two-year-old queen was referred to the surgery section of veterinary hospital with lateral recumbency position and the primary diagnosis of dystocia. The queen was highly lethargic and dehydrated, with a pale mucous membrane, a rectal temperature of ۳۷.۳ °C, and no vaginal discharge during first inspection. The primary examination revealed a big mass in the abdominal cavity, which was followed by other diagnostic investigations. Due to a huge and encroaching tumor and the patient's owner's refusal to accept any further therapies, the queen was euthanized during an exploratory celiotomy. This report describes a large Hemangiopericytoma (HPCy) in a domestic short-haired queen diagnosed based on physical examination, radiography, ultrasonography, histomorphology, and immunohistochemical reactivity. The results of pathology revealed a whorls around blood vessels and the "fingerprint" pattern of tumor with negative S-۱۰۰ immunohistochemistry staining.   In dogs, HPCy is a common neoplasm, but it is a seldom finding in cats. There is no previous report of HPCy in the abdominal cavity as observed in the presented case to the authors' knowledge.

hemangiopericytoma, cat, Immunohistochemistry, abdominal cavity, Histomorphology