Cancer Treatment for Pets:
VOSRC Dispels the Myths & Helps Remove the Fear

At VOSRC, we want to dispel the myths regarding cancer and help remove the fear that many people feel when their pet has had a cancer diagnosis. When it comes to treating our patients, we always aim to improve quality of life. This involves delivering treatments that are effective in eliminating or reducing the disease that is causing the clinical signs or sickness while minimizing side effects. Compared to human medicine, it is important to understand that the starting dosages of chemotherapy drugs used in veterinary medicine are much lower with fewer numbers of drugs given at one time. If doses are reduced too far, the efficacy is lowered and the cancer is ultimately not being treated. Thus, improvement in quality of life will not be attained.

We offer conventional cancer treatment, with which you may be familiar, such as surgery, chemotherapy, immunotherapy, and radiation—but always carefully tailored to the individual animal.

We are also constantly striving to enhance our arsenal. Additional therapies, such as molecular targeted therapy with commercially available products and immunotherapy using tumor vaccines and other biologics, are also available.

New approaches in multimodality therapy have been developed or used at VOSRC. One was the development of chemoimmunotherapy in lymphoma, first using the dog’s own lymph nodes (tumor) as a vaccine following induction of remission with chemotherapy. This published work led to the development of the canine anti-lymphoma monoclonal antibody, CLMab 231, as it was known commercially.

Chemoimmunotherapy with CLMab 231 showed longer remission durations without continuous chemotherapy and prolonged survival times (Jeglum, 1996, 2008). Chemotherapy drug resistance also was modified as later shown in human lymphoma patients. In fact, subsequent human trials, on the heels of the canine work, have made treatment with chemotherapy and monoclonal antibody the gold standard approach to treating non-Hodgkin’s lymphoma. We are hopeful that monoclonal antibody therapy will become available again. In the meantime, chemoimmunotherapy is available at VOSRC using lymphoma vaccines made from the dog’s own lymph node in our on-site research laboratory in West Chester. Dogs are induced into clinical remission with 8 weeks of chemotherapy followed by maintenance tumor vaccine.

Another approach developed in humans is hypoxic cell sensitization. This is when low doses of chemotherapy drugs are delivered prior to radiation therapy to sensitize cells that are radiation resistant due to low oxygen content (hypoxic cells). We use several different protocols applying this approach in our radiation patients with carcinomas and sarcomas.

An alternative treatment approach, known as metronomics, is emerging as an effective palliative treatment in diseases where conventional treatment is not effective or has failed. It is a form of anti-angiogenesis therapy in which agents are used to inhibit blood vessel formation to tumor cells, thus suffocating the cancer and resulting in its death. The approach was largely founded in pediatric oncology, in cancers that were considered untreatable, but in hopes of prolonging survival with improved quality of life. It uses combinations of oral agents including continuous low doses of chemotherapy drugs, non-steroidal anti-inflammatory drugs, and the antibiotic doxycycline. Metronomics offers an economically more feasible approach for some owners. At VOSRC, this approach has shown particular promise in hemangiosarcoma following combination chemotherapy.

Other multimodality approaches are addressed elsewhere in the website. Above all, know that we will work with you to develop the kind of treatment that is right for you and your pet, taking into consideration your personal needs, expectations, and comfort level.