Very few studies, often with very small cohortes, tended to prove chemotherapy efficiency against canine agressive mammary carcinomas, either on the metastasis or on the median survival of dogs after surgery and chemo, and this was not confirmed by other studies. As a result, we lack standardized efficient protocols that exist in human cases according to their grade and stage. In this case report of a relapsing grade III solid mammary carcinoma evolving into prominent lymphatic intravascular invasion with mutifocal nodal extension (stage 4), we applied an intensive treatment combining high dose surgery and intensive adjuvant chemotherapy. This adjuvant chemo combined a carboplatin maximal-tolerated-dose chemotherapy, with doses adjusted as necessary and a metronomic chemotherapy with firocoxib, toceranib and chloraminophen, progressively added together and carefully monitored. Adapting the doses allowed to avoid adverse events and to obtain 237 days of survival with good quality of life. To our knowledge, it is the first description of such a combination of treatment. That result should be confirmed by a prospective large-scale study.