Diagnosis of Ocular Metastasis of Transmissible Venereal Tumor by Cytology - Case Report
The transmissible venereal tumor (TVT) affects primarily the round cells of the mucosa of external genitalia in dogs of both sexes. The metastasis of this type of tumor is rare, especially in the lips, oral mucosa and peritoneum, or in organs such as the tonsils, eye, liver, spleen, kidney, lung and musculature. The diagnosis can be made by biopsy or cytology.
The aim of this case was to prove the efficiency of cytology for diagnosis of TVT in different sides without the necessity of an invasive procedure.
A bitch, 5-year-old, mixed-breed presented with a reddish and friable mass in the left orbit. In the anamnesis the owners said that the dog had received chemotherapy for TVT when they adopted it, four months before. The cytological exam was made by imprint of the mass in the left eye with a histological slide and after staining in Diff-Quik and Giemsa.
We found a high number of cells with a rounded morphology, scarce cytoplasm and finely granular, presence of vacuoles in the cell periphery and a round central nucleus with coarse chromatin and one or two prominent nucleoli, with the diagnosis of TVT. After the animal was routed to chemotherapy and after 6 sessions had full remission of the mass.
The cytological exam is a powerful and efficient method of diagnosis for transmissible venereal tumor, with quick, cheap and minimal tissue injury procedure.