Uterine neoplasia in a 14-year old Quarter Horse mare

Abstract

Uterine neoplasia in a 14-year old Quarter Horse mareIn the present report a case of uterine neoplasia in a Quarter Horse mare is described. The fourteen-year old Quarter Horse showed honeylike vaginal discharge for more than one year as well as pollakiuria and polyuria. Two weeks before the mare was referred she was presented to the regular veterinarian because of red vaginal defluxion. He diagnosed a huge mass within the uterus. Upon referral, rectal temperature, heart rate and respiratory rate of the mare were within normal limits. Transrectal palpation and ultrasound was performed for confirmation of the uterine neoplasia. In the course of hysteroscopy a tumor associated with the wall of the corpus uteri was found, which was 23 x 21 x 18 cm in size. An ovariohysterectomy was performed. For histopathological examination different representative localisations of the uterine neoplasia were prepared and analysed with H.E. staining. Immunohistochemical examinations were performed for the confirmation of desmin and a-actin expression in tumor cells. Then days after ovariohysterectomia the mare left the clinic in a good condition. Histological findings were an infiltrative growing leiomyoma with signs of malignity. Uterine neoplasia in mares is uncommon. Leiomyomas are benign neoplasia of the smooth muscles. They are predominantly seen in the female genital tract of the large domestic animals and can also occur in the walls of the urinary bladder or the intestine. As a differential diagnosis, there are also leiomyosarcomas in all domestic animals, but they are very rare. They can be distinguished from benign neoplasia by pleomorphia, a high mitosis rate and infiltrative growing