Study Results:
Lymphoma is one of the most common cancers in dogs. Its cause is unknown, but genetic, environmental and infectious-disease factors may play roles in the cancer’s development. Previous research suggested a link between lymphoma and infections with hemoplasmas-bacteria that adhere to red blood cells and can persist in a dog’s blood without causing clinical signs of disease. The goal of this study was to determine whether dogs with untreated lymphoma have a higher prevalence of hemoplasma infection than dogs with untreated mast cell tumors or sarcomas.
Scientists collected blood samples from dogs with soft-tissue sarcoma, lymphoma and mast cell tumors that had not been treated with chemotherapy. The researchers detected hemoplasmas in 5 percent of the dogs tested and identified the species of infecting hemoplasma for each positive sample. The frequency of hemoplasma infection did not differ in dogs with lymphoma compared with the frequency in dogs with soft-tissue sarcoma or mast cell tumors. Because their previous studies showed a higher frequency of hemoplasma infections in dogs with lymphoma that were being treated with chemotherapy, the researchers hypothesize that chemotherapy may contribute to increased hemoplasmas or may predispose a dog to infection with these organisms. They now plan to evaluate the infected dogs to determine whether subsequent chemotherapy was associated with unexpected complications (such as hemolytic anemia) in these dogs. (D08CA-087)
