Background:
Lymphoma is the lymphoid tissue neoplasm. Ocular lymphoma is one of the most prevalent neoplasm of the eye in felines and comprises for about ۱۵% of all feline intraocular neoplasms. According to the World Health Organization (WHO) staging guidelines, ocular involvement of lymphoma indicates advanced (stage V) disease, and generally poor prognosis given even with treatment. Methods: A female out-door domestic long-haired cat presented to the Veterinary Medicine hospital of Shiraz University with a history of prolonged intraocular bleeding in the right eye. Ophthalmologic examination of the right eye revealed chemosis, hemorrhage, absence of the direct and consensual pupillary light reflex (PLRs), menace response and dazzle reflex. After complete diagnostic work-up including complete blood count and serum biochemistry profile, the right-eye enucleation was performed and an excisional biopsy of the eye tissue was submitted for histopathology. Due to the owner’s decision to decline investigation, elected euthanasia was chosen. Results: Cell blood count and serum biochemistry profile results showed leukocytosis, anemia, thrombocytopenia, azotemia, an increased alkaline phosphatase activity, hyperproteinemia, hypoalbuminemia and low albumin/globulin ratio. Histopathologic examination of the conjunctival tumor revealed well differentiated, monoclonal small lymphocytes with monocytoid cytology, prominent plasmacytic features and lymphoepithelial lesions. The final diagnosis was low-grade conjunctival lymphoma. Conclusion: This report describes a conjunctival lymphoma localized to the ocular tissue of a cat, based on clinical and histopathological examinations. The absence of menace and dazzle reflexes, indicates that the optic nerve is affected. An ophthalmological examination may be an essential part of the eye lymphoma staging in felines. In cases with central nervous system involvement, the prognosis tends to be poor.
