Malignant lymphoma in nasal cavity and paranasal sinuses of a dog

A case of a canine large cell type T-cell lymphoma, with features of high-g rade malignancy is described. The tumour was found confined in the nasal ca vity and the paranasal sinuses of a crossbred German Shepherd dog. Histolog ical examination revealed the features of a highly malignant large cell lym phoma. Ultrastructurally, the lymphoid tumour cells bore cytoplasmic protru sions that interdigitated tightly. From a panel of tumour markers used, the neoplastic cells were stained only for vimentin. Immunophenotyping of the tumour cells by means of CD3, CD79, kappa -light chains and lambda -light c hains detection was undertaken. The tumour stained only for CD3 and was cla ssified as T-cell lymphoma.