The immune system is the body’s defense against organisms or even objects that will harm us such as bacteria, viruses, foreign bodies (like a splinter) and yes, cancer cells. Cancer cells are trickier targets though, because in many ways they still look like us. This makes detection by our immune system very challenging and while eradication of cancer cells by our immune system alone is possible, these innate defense mechanisms can be easily overwhelmed.

Immunotherapy is the artificial stimulation of the immune system to seek out and destroy cancer cells. Immunotherapy is sometimes used alone or in conjunction with other therapies such as surgery, radiation therapy, chemotherapy and integrative medicine, thus potentially creating a synergistic and/or more potent effect. This is a relatively new and exciting field of cancer treatment and prevention. As such, our canine and feline patients have access to just a few immunotherapies compared to their human counterparts. However, the field is growing and research is ongoing that hopefully will change the way we think about, treat and one day prevent canine and feline cancers.

The most widely available and most studied immunotherapy currently used in veterinary oncology is the canine malignant melanoma vaccine. There are other canine cancer vaccines available but their efficacy and safety data are not as robust yet. 

Finally, as mentioned above, this is a growing field and there are several clinical trials currently being conducted nationwide that will hopefully offer our patients even more options. These include investigations into immunotherapies for canine osteosarcoma, canine lymphoma, feline sarcomas and canine hemangiosarcoma.  We look forward to informing you about new therapies as they become available.