Post-traumatic ocular lymphoma in three rabbits (Oryctolagus cuniculus)

This report describes post-traumatic ocular lymphoma in 3 companion rabbits; 2 rabbits with unilateral disease and 1 with bilateral disease. Historical findings suggestive of a traumatic event included either external unilateral ocular trauma or bilateral phacoemulsification. Severe corneal changes, presence of an anterior chamber mass(es), low intraocular pressures, and ocular discomfort were noted on ophthalmic examinations. All eyes were treated for variable courses with standard ophthalmic topical medications (antibiotic, anti-inflammatories, and steroid) and systemic anti-inflammatories. Based upon progression of disease, all affected eyes were ultimately enucleated; lenticular capsular rupture and a round cell neoplasm effacing normal structures with variable mitotic indices were noted on histopathology. Neoplastic lymphocytes strongly expressed CD79a via immunohistochemistry and lacked expression for CD3, indicating B lymphocyte lineage and not of T cell lineage. A single animal had evidence of local metastasis to a regional lymph node. Post-traumatic sarcomas have been reported in this species previously, however, these cases are the first reports of this novel round cell variant, named post-traumatic ocular lymphoma due to the B cell lineage confirmed through immunohistochemistry. Clinicians should be aware of this clinical presentation and the possibility of metastasis when evaluating ocular pathology in this species.