Disseminated transmissible venereal tumor on skin, eyelids and genital in a male dog. Case report

Abstract

Canine venereal transmissible tumor (CTVT) is a round cell benign neoplasia that affects the external genital mucous which is transmitted during coitus with infected dogs. The normal canine behaviour such as smelling and sucking allow the tumoral cells to implant into extragenital zones with subsequent metastases formation. This report described a dog with multiple skin nodules localised in the thoracolumbar area and eyes. The nodules were ulcered and alopecic with purulent fluid around them. A granulomatous mass with focal necrosis area was also detected with bilateral keratitis. Citological analysis of skin nodules, eyelid tissue and granulomatous tissue on the base of the penis suggested a CTVT, and the histopathological analysis confirmed the diagnosis of CTVT. Also LINE-1 rearrangement in c-myc was detected as a genetic alteration of the CTVT. A chemotherapy protocol was started with vincristine sulfate. Haemograms were used previous to each chemotherapy sessions to prevent myelosuppression. A moderate non regenerative anemia was observed after the third session but it was resolved by discontinuing chemotherapy for two weeks. The chemotherapy was effective to eliminate the CTVT after six sessions.