Lomustine for treatment of canine transmissible venereal tumor

• Published in: Ciência rural 2023, Vol.53 (8)
• Main Authors: Costa, Thiago Souza, Paiva, Felipe Noleto de, Manier, Bruna Sampaio Martins Land, Conceição, Cecília Lopes da, Reis, Andressa Aparecida de Lima, Fernandes, Julio Israel
• Format: Article
• Language: English
• Subjects: AGRONOMY
• ISSN: 0103-8478; 1678-4596; 1678-4596
• DOI: 10.1590/0103-8478cr20220120

Canine transmissible venereal tumor (TVTC) is a highly casuistic transmissible neoplasm in Brazil. Chemotherapy with vincristine sulfate is considered the treatment of choice, but the need for weekly applications and hematological monitoring, in addition to costs, are obstacles to owners’ adhesion to the treatment. Lomustine is an alkylating class antineoplastic agent, and because it is administered orally, it is a more practical and less costly treatment option for the owners of animals with neoplasms sensitive to the drug. This study evaluated the therapeutic efficacy of lomustine in dogs affected by TVTC. Twelve dogs with cytopathological diagnosis of natural genital TVTC were selected. The dogs were submitted to the experimental protocol with lomustine administration at doses of 70 to 85 mg/m2 orally every 21 days, totaling a maximum of two administration cycles. The animals were reevaluated every 7 days until a maximum of +49 days after the first dose of lomustine, to monitor the regression of neoplastic lesions through measurements. Among the 12 dogs submitted to the lomustine protocol, 8/12 achieved complete remission of the neoplasm and were considered cured (66.6%), 1/12 had partial response to treatment (8.33%) and 3/12 had stable disease (25%). Important adverse effects such as severe neutrophilic leukopenia were detected in 3/12 dogs (25%). The clinical study indicated that lomustine may be a treatment option for TVTC. RESUMO: O tumor venéreo transmissível canino (TVTC) é uma neoplasia transmissível de elevada casuística no Brasil. A quimioterapia com sulfato de vincristina é considerada o tratamento de escolha, mas a necessidade de aplicações semanais e acompanhamento hematológico, além dos custos, são obstáculos à adesão dos proprietários ao tratamento. A lomustina é um antineoplásico da classe dos agentes alquilantes e, por ser administrado por via oral, representa um opção de tratamento mais prática e menos onerosa para os proprietários de animais com neoplasias. O objetivo deste estudo foi avaliar a eficácia terapêutica da lomustina em cães acometidos por TVTC. Foram selecionados 12 cães com diagnóstico citopatológico de TVTC genital de ocorrência natural. Os cães foram submetidos ao protocolo experimental com administração de lomustina nas doses de 70 a 85 mg/m2 por via oral a cada 21 dias, totalizando no máximo dois ciclos de administração. Os animais foram reavaliados a cada sete dias até um máximo de +49 dias após a primeira dose de lo