Bilateral ovarian teratoma in a free-living Iberian red deer (Cervus elaphus hispanicus)

Abstract

CASE HISTORY: A 8.5x5.7x5 cm irregularly shaped mass was detected in the location of the left ovary of a 9-year-old Iberian red deer (Cervus elaphus hispanicus) hind shot during a hunting drive. PATHOLOGICAL FINDINGS: On the cut surface, the mass consisted of numerous fluid- or keratin-filled inter-communicating cysts, separated by connective tissue containing solid nodules of dark-coloured foci and hairy skin. The right ovary was of normal size, but contained a 1.5 cm mass of hairy skin and spongy structures. Histologically, the large mass comprised differentiated structures such as cartilage, fibrous connective tissue, smooth muscle, stratified squamous keratinised epithelium, cuboidal multi-layered and respiratory epithelium, clusters of pigment-laden cells, hair follicles, nervous tissue and glandular structures. The hind had a grossly and microscopically normal uterus that contained a 449.5 g female fetus. DIAGNOSIS: Bilateral mature ovarian teratomas. CLINICAL RELEVANCE: This case describes the first known description of an ovarian teratoma in a free-living red deer. The tumour had unique features, such as bilateral presence and concurrency with a normal pregnancy.