Oncolytic activity of Newcastle disease virus strain zg1999hds on oral malignant melanoma in dog: A case report

Abstract

Oral malignant melanomas (OMMs) are the most frequent neoplasms in dogs older than 10 years. Small breeds with heavily pigmented oral mucosa are at a greater risk to get this tumour disease. The outcome of OMMs is related to the clinical stage at the time of diagnosis, e.g. tumour size, presence of local or distant metastases, presence or absence of ulceration and anatomic site. The treatment of OMMs consists of radical resection of the primary tumor, and, in relation to the malignant behavior of the disease -radiotherapy, chemotherapy or immunotherapy. Other forms of therapy, such as immunotherapy using cytokines and specific vaccine, have also been tested, but with controversial results. Oncolytic viruses have not been used in OMMs treatment in dogs, although the promising results with melanomas in humans were achieved. Here, we describe the antitumour effect of the Newcastle disease virus strain ZG1999HDS that was given locally and systematically to a dog with OMMs. After two sets of virus application, the melanoma tissues were necrotized with evident neutrophilic demarcation of the remnants of the viable tumor cells in which melanin pigmentation was no longer present.