Ocular manifestation of lymphoma in a cat

By Emma Scurrell

A 12-year-old male DSH cat presented with bilateral uveitis and diffuse thickening of the iris associated with a shallow anterior chamber. Below are images from the aqueocentesis sample (fig.1) and subsequent gross and histopathological specimens (figs.2&3) from one of the enucleated globes

Fig 1. In this aqueocentesis cytospin prep, there are low numbers of large neoplastic lymphocytes. Compare the size of the lymphocytes (specifically their nuclei) to that of the surrounding red blood cells to assess the cell size more objectively. To give you a better idea of cell size, the size of the nucleus in a small lymphocyte approximates that of a red blood cell.

Fig 2. This is a gross specimen of the enucleated globe. The iris and ciliary body are diffusely thickened and discoloured white. Note the associated shallowing of the anterior chamber.

Fig 3. H&E section revealing sheets of densely-packed large neoplastic lymphocytes. Mitotic figures were frequent (not shown in this image).

Final Diagnosis

Uveal lymphoma (large cell, high grade)

Discussion

Cases of large cell/high grade lymphoma affecting the eye in both dogs and cats should be viewed as a multisystemic disease process even if the initial clinical manifestation appears to be restricted to the eye(s). Primary ocular lymphoma can occur but this is less common. Aqueocentesis can be used as a diagnostic tool in an attempt to confirm the diagnosis and is probably most useful when lymphoma is suspected. Enucleation can also be used to confirm the diagnosis in an irreversibly blind eye but should not be viewed as a curative procedure in the majority of cases.