An abdominal teratoma in a yearling Irish Cob with a strangulating obstruction of the small intestine

Abstract

Summary A yearling Irish Cob stallion was presented to De Morette Equine clinic for severe acute abdominal pain, nonresponsive to analgesics and sedatives. Rectal palpation and a limited transabdominal ultrasonographic examination led to the presumptive diagnosis of a strangulated obstruction of the small intestine. The painful behaviour of the pony did not allow conservative treatment and surgical exploration was denied by the owners for financial considerations. On necropsy, a large cystic mature teratoma was adhered to the ventral body wall, the mesenteric root, omentum and intestines. Teratomas are rare in man and animals, and an extragonadal intraperitoneal location has not previously been reported in the equine species.

Testicular Teratoma in a Unilateral Right-Sided Abdominal Cryptorchid Horse

“…In our case, fibrous tissue, cysts, bone, adipose tissue, and mineralized areas were found by light microscopy. A variety of tissues can be identified in teratomas including skin, muscle, tooth, hair follicles, bone, and cartilage [2,12,14,15]. The actual prevalence of testicular teratoma in global equine population is difficult to estimate without large retrospective and prospective studies, because most stallions are castrated at an early age.…”

“…The most common tumors reported in mammalian species are Sertoli cell tumors, Leydig cell tumors, seminomas and teratomas [14,15,17]. Teratoma is quite rare in horses [2,5], however, it is the most frequent testicular tumor reported in young stallions, between 1 and 5 years-old [14,15,17].…”

Equine colic caused by neoplasia

“…Mesenteric rents are a fairly common cause of intestinal strangulation, and the cause of the rent is not usually apparent. The authors of the present case (Arensburg et al 2012) speculate that the rent could have been the result of the attachment of the tumour to the mesentery, and that is likely. The failure to detect this tumour ante mortem was the result of its location and the horses' level of pain.…”

“…Teratomas in the horse are usually of testicular origin, do not cause colic and are discovered when searching for a cryptorchid testicle. However, the case report by Arensburg et al . (2012) provides evidence that teratomas in the horse can arise from other locations, as is described in man.…”

“…Successful therapy, either curative or palliative, for colic caused by neoplasia depends on the extent of the gastrointestinal lesion and the ability to remove the tumour. Most horses with colic caused by neoplasia will be aged >10 years; however, as the case report by Arensburg et al (2012) in this issue describes, not all colic episodes caused by tumours occur in older horses. Neoplasia should be considered as a possible cause of colic if a patient has shown weight loss, an abdominal mass is detected on physical or ultrasonic examination, the patient is a cryptorchid, or if excessive abdominal fluid (particularly transudate or haemorrhage) is present.…”