Equine testicular teratoma.: Case report

The authors present the characteristics of equine testicular teratomas. An abnormal cryptorchid testicle was removed from the abdominal cavity of a 3 year old Hungarian Half-bred stallion. One of the testicles had removed 7 month before, but excessive masculine and agressive behaviour still remained. Rectal examination was not helpful in locating the position of the testes. With the stallion under general anesthesia, it was placed in dorsal recumbency for cryptorchidectomy. Exploratory surgery via the right inguinal approach was undertaken. The abnormal testicle measured 18 cm by 12 cm and 1.6 kg. Incision of the testicle revealed cysts filled with fluid and hair. Histologically, the cyst walls were completed from keratinizing epithelium and mucous epithelium. Collagenous connective tissue comprised most of the cyst walls. Cartilage-, bone-, central nervous- and collagenous connective tissues filled the space among the cysts. By histologic examination of the testicle the alteration was classified as a matured teratoma. 3 month later excessive masculine and agressive behaviour of the horse disappered. 9 month after the operation with clinical examination signs of postoperative complication and metastasis were not found. Nowadays the horse is used for show jumping.