Immunophenotypic characterization of lymphomas from the mediastinum of young ferrets.

OBJECTIVE

To determine the phenotype of naturally developing lymphomas in young ferrets.

ANIMALS

10 ferrets with lymphoma.

PROCEDURE

Neoplastic tissues were graded histologically according to the National Cancer Institute's Working Formulation for non-Hodgkin's lymphoma and phenotype was determined by means of immunohistochemical staining. A polyclonal anti-human CD3 and a monoclonal anti-human CD79 antibody were used to classify the lymphomas in situ as T-cell or B-cell origin. Specificity of antibodies was determined by evaluating lymphoid tissue from normal ferrets in situ, which was confirmed by western blot analyses.

RESULTS

All 10 ferrets had clinically aggressive tumors, irrespective of the phenotype. Nine ferrets had T-cell lymphoma that extensively involved the mediastinum. Remnants of thymic tissue, indicative of thymic origin, were identified in lymphoma of these 9 ferrets. One ferret had a B-cell multicentric lymphoma without involvement of the mediastinum.

CONCLUSIONS

The majority of lymphomas in these young ferrets involved the mediastinum and were of T-cell phenotype. Impact for Human Medicine-There are many similarities between the lymphoma syndrome of ferrets and the condition documented for cats and children with lymphoma of the mediastinal area.

CLINICAL RELEVANCE

Differential diagnoses for young ferrets with clinical signs of lethargy or respiratory distress should include T-cell lymphoma of the mediastinum.