Histopathological and Cytological Analysis of Transmissible Venereal Tumor in Dogs After Two Treatment Protocols

Abstract

The transmissible venereal tumor (TVT) is a contagious neoplasm of round cells that frequently affect dogs. The treatment consists of chemotherapy being more effective the vincristine alone, however the resistance emergence to this agent due multidrug resistance of the P-glycoprotein (P-gp), a transporter protein encoded by the MDR1 gene, has been taking the association with other drugs. Recent studies demonstrated the antitumoral effect of the avermectins when associated to the vincristine in the treatment of some neoplasms. Therefore, the objective of the present study was to compare the effectiveness of standard treatment of TVT with vincristine only when compared to combined treatment with vincristine and ivermectin, evaluated through number of applications of the two protocols, histopathological and cytological analysis from 50 dogs diagnosed with TVT during the period of 2007 to 2010. The combined protocol significant reduced the number of applications and cytological and histopathological findings collaborate with the hypothesis that the combination of vincristine and ivermectin promotes faster healing than the use of vincristine alone. Combination treatment with vincristine and ivermectin could be in the future an excellent therapeutic alternative for the treatment of TVT for probably reducing the resistance to vincristine, simultaneously reducing the cost of TVT treatment and promoting a faster recovery of the dog

Primary oral and nasal transmissible venereal tumor in a mix-breed dog

“…Treatment should be directed at tumor remission and elimination of secondary infections and other complications. Medical treatment with chemotherapeutic agents such as vincristine has been shown to be effective [2,9,14] . We started treatment by intravenous injection of vincristine sulfate at the dose of 0.025 mg/kg body weight weekly.…”

“…Diagnosis of TVT is based on the history, clinical signs, cytology and histopathology [9] . Chemotherapy is the choice of treatment [2,9] . Although, there are reports of secondary occurrence of oral and nasal TVT in dogs, primary occurrence of these sites is almost rare.…”

“…Canine transmissible venereal tumor (TVT) is a round cell neoplasm with widespread distribution, particularly in region with tropical and subtropical climates [1,2] . This canine tumor transmits coitally with no breed or sex predilection [3,4] .…”

Tumor Venéreo Transmissível Primário Em Terceira Pálpebra Com Migração Para Cavidade Nasal – Relato De Caso

“…Devido à regressão espontânea não ser observada em muitos casos de TVT de ocorrência natural, o tratamento é recomendado (KOMNENOU et al, 2015). LAPA et al (2012) estipularam que as condutas terapêuticas preconizadas são a excisão cirúrgica, quimioterapia antineoplásica, radioterapia e imunoterapia, sendo o tratamento quimioterápico considerado de escolha por apresentar maior eficácia e melhor prognóstico para obter-se remissão completa. De acordo com STETTNER et al (2005), os agentes mais comuns da quimioterapia usada para o TVT são a vincristina, a vimblastina e a doxorrubicina.…”

Estudo retrospectivo de tumor venéreo transmissível em cães (Canis lupus familiaris) na região de Garça, São Paulo, Brasil

“…Diversos protocolos terapêuticos têm sido descritos para o tratamento do TVT, incluindo a quimioterapia, a biopsia excisional, a radioterapia e a imunoterapia (Santos et al, 2008;Lapa et al, 2012;Saibaba et al, 2015). Contudo, o uso do sulfato de vincristina tem sido o protocolo mais preconizado para o tratamento (Pigatto et al, 2011;Antonov, 2015;Rani e Pazhanivel, 2015;Saibaba et al, 2015).…”