Clinico-pathological studies on the effect of different anti-neoplastic chemotherapy regimens on transmissible venereal tumours in dogs

Abstract

Thirty-two dogs affected with transmissible venereal tumour (TVT) were divided into three treatment groups. In group I vincristine sulphate at 0.025 mg/kg body weight, in group II vinblastine sulphate at 0.150 mg/kg body weight, and in group III vinblastine sulphate at 0.100 mg/kg body weight plus methotrexate at 0.35 mg/kg body weight were given intravenously at weekly intervals. Biopsies were performed on days 0, 3, 7 and 14. The tissues were preserved in 10% neutral buffered formalin and processed routinely for haematoxylin and eosin staining. Histopathologically, the untreated TVT was characterized by sheets or bundles of mostly rounded cells having a large, highly basophilic nucleus with a prominent, highly basophilic necleolus. Both vincristine and vinblastine primarily affected the nuclei of neoplastic cells, causing condensation, karyorrhexis and karyolysis within 3 days of chemotherapy. The regressing tumour mass showed marked infiltration by lymphocytes, lymphoblasts and macrophages by day 7. There was nearly complete regression of the tumour by day 14, as shown by the almost complete loss of neoplastic cells, with fibrous tissue substitution. However, in group III, the changes occurred more slowly and more injections were needed for complete regression. In both groups I and II, 11/12 of the animals responded completely to the chemotherapy within 3 weeks, while in group III, 6/8 of the dogs responded to the treatment by 21-28 days.

The changing global distribution and prevalence of canine transmissible venereal tumour

“…Vincristine is known to be a very effective treatment for CTVT [49],[53],[87]-[90]. We asked respondents to report the type and effectiveness of treatments they typically administer for CTVT (Figure 5C).…”

Características E Incidência Do Tumor Venéreo Transmissível (Tvt) Em Cães E Eficiência Da Quimioterapia E Outros Tratamentos

“…As neoplasias sem lesão primária genital constatadas por PEREZ et al (1994) e GINEL et al (1995 A unanimidade na literatura médica veterinária sobre a eficácia da administração de sulfato de vincristina no tratamento de TVT (OLGIVIE, 1996, WHITE, 1991e MORRISON, 1998 certamente fundamentou a opção pela quimioterapia antineoplásica para o controle de TVT, empregada em todas as clínicas de Curitiba e Região Metropolitana investigadas.…”

“…Observam-se fileiras de células similares a macrófagos, células variando do formato redondo ao poliédrico (WHITE, 1991) medindo 15-30 mm de diâmetro (SANTOS, 1988), citoplasma azul-claro com a presença de vacúolos distintos, sendo pequena a relação núcleo/citoplasma (WHITTE, 1991). Nessas células, o núcleo é grande, basofílico e central (SINGH et al, 1996). De acordo com LOAR (1992) constatou-se presença de septos conjuntivos que isolam grupos de células, evidenciando disposição trabecular, além das figuras mitóticas que podem ser freqüentes.…”

“…Ainda como alternativas para quimioterapia antineoplásica, podem ser empregados fármacos como clofibrato (BHAT e AHMAD, 1988), ciclosfosfamida (HOQUE et al, 1993), doxorrubicina, sulfato de vinblastina e metrotexato (SINGH et al, 1996). Muitos desses fármacos podem ser utilizados quando se pretende reduzir o tamanho do tumor para posteriormente submetê-lo à exérese cirúrgica.…”

Multifocal metastatic cutaneous and mucosal transmissible venereal tumour in a female puppy

“…Reported side effects are generally mild to non-existent, but may include anti-mitotic effects on the bone marrow, such as mild neutropenia and mild leucopenia, and mild gastrointestinal upset. Other side effects are possible (Amber and others 1990, Singh and others 1996, Tella and others 2004, Nak and others 2005, Varughese and others 2012). As with previous reports, this patient responded well to vincristine therapy, experiencing only mild side effects of leucopenia, eosinopenia, neutropenia, diarrhoea and hyporexia.…”