Retinoblastoma in the eye of a llama (Llama glama).
METHODS
A 6-year-old, pregnant female llama experienced a 6-month history of epiphora, buphthalmos, and acute loss of vision in the left eye. The condition was unresponsive to topical antimicrobial and anti-inflammatory therapy and progressed to corneal rupture.


METHODS
Transpalpebral enucleation was performed and an intraorbital silicone prosthesis was implanted. The eye was fixed in formalin and processed according to routine paraffin technique. Sections of a mass were immunohistochemically prepared routinely and stained for glial fibrillary acidic protein (GFAP), S-antigen, and rhodopsin.


RESULTS
Gross, histopathologic, and immunohistochemical analysis revealed a retinal tumor consistent with a retinoblastoma. The neoplastic tissue formed Flexner-Wintersteiner and Homer-Wright rosettes, originated from the retina, and demonstrated photoreceptor differentiation with S-antigen and rhodopsin expression. Neoplastic cells were negative for GFAP. Four years after enucleation, the llama showed no signs of recurrent neoplasia.


CONCLUSIONS
This report describes the diagnosis and successful treatment of the first known retinoblastoma in a llama.
Fugaro
Michael N
MN
Department of Veterinary Clinical Sciences, Purdue University, West Lafayette, IN 47907, USA. michael.fugaro@ag.state.nj.us
Kiupel
Matti
M
Montiani-Ferreira
Fabiano
F
Hawkins
Jan F
JF
Janovitz
Evan B
EB
D000818:Animals; D002161:Camelids, New World; D003937:Diagnosis, Differential; D005260:Female; D007150:Immunohistochemistry; D011247:Pregnancy; D011252:Pregnancy Complications, Neoplastic / Q000175:diagnosis / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D019572:Retinal Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D012175:Retinoblastoma / Q000175:diagnosis / Q000473:pathology / Q000601:surgery / Q000662:veterinary*