A lesion was identified in the eye of a juvenile llama, and preliminary cli
nical findings included anterior uveitis and an exudative retinal detachmen
t suggestive of infectious disease. However, histopathologic evaluation of
the enucleated globe revealed an intraocular neoplasm composed of primitive
neuroepithelium forming ribbons, cords, and rosettes, heteroplastic elemen
ts including spindle cells in a loose myxomatous matrix, and islands of wel
l-differentiated hyaline cartilage. Immunohistochemically, neoplastic cells
were positive for vimentin and neuron-specific enolase. Spindle cells were
multifocally positive for desmin and muscle specific actin, indicating dif
ferentiation towards myofibers. These findings are consistent with a diagno
sis of malignant teratoid medulloepithelioma; an extremely rare ocular neop
lasm that affects children and young animals.