This prospective therapy study aimed to evaluate the clinical effect of autologous, monocyte-derived dendritic cell (DC) therapy in canine hemangiosarcoma stage II after splenectomy. The study involved 42 dogs with stage II and 452 dogs diagnosed with splenic hemangiosarcoma that underwent splenectomy. The median survival time for the total group of the 42 dogs with stage II was 203 days. The median survival for the group that received the full DC therapy (n=34) was 256 days, with a 29 % one-year survival rate and a hazard ratio of 0.30, adjusted to age and body weight. DC yield at the beginning of treatment was significantly related to patient survival.
Despite limited progress in demonstrating increased survival time after diagnosis of hemangiosarcoma, immunotherapies have gained attention as a new treatment approach. Dendritic cell (DC) therapy is one of the current treatment options in translational veterinary medicine, as it presents tumor antigens to T-cells, enabling the immune system to establish a response toward these cells. Cancer immunotherapies with DCs have been used in multiple clinical trials.
Most studies discussed primed DCs and focused on the maturation of DCs by adding tumor antigens during cultivation. However, these studies do not consider the migratory capacity of DCs. In situ or in vivo priming should be considered, as DCs can internalize and process antigens released by cancer cells into the tumor microenvironment.
Autologous DC therapy was first described for horses with equine sarcoids, and case studies have shown the effect of autologous unprimed DCs. DC therapy has also been applied in dogs in combination with the cytokine IFN-γ to investigate its effect on clinical outcomes. This broader prospective study aims to obtain significant findings from a larger sample size.
While further evidence is needed, they conclude that autologous, monocyte-derived DC therapy is a viable alternative to standard treatment methods of canine splenic stage II hemangiosarcoma.
