Chemotherapy is the use of drugs or chemical agents to kill cancer. This treatment works by attacking rapidly growing cancerous cells in the body. Each individual chemotherapy drug works through different mechanisms and has different potential side effects. Chemotherapy is typically administered by injection into veins, under the skin, or into the tumor. Some chemotherapy is also given in pill form. How chemotherapy is given depends on your pet’s specific medical needs. We are happy to discuss all your options at your appointment. For many people, the word chemotherapy brings up negative images. But there are many differences between how pets with cancer and people with cancer are treated. It is important to understand that our goal is for pets undergoing chemotherapy to have no side effects from treatment. We work towards this goal by carefully choosing drugs and doses, administering supportive drugs during treatment, and by educating owners about at-home care. Pets undergoing treatment for cancer need lots of love and attention. Your pet may even bond with the veterinary staff due to the extra attention they will receive during their appointments.
This method of treatment allows chemotherapy drugs to better reach their intracellular target; studies have shown increases in cytotoxic activity up to 1,000-fold. The process includes injecting a chemotherapeutic agent followed by local electrical pulses. ECT can be used to treat local disease and as an adjuvant to surgery. For some cancer types, ECT is a great alternative option to radiation as it is typically less expensive, requires fewer anesthetic procedures, and has few long-term side effects. To learn more about see: Electrochemotherapy with intravenous bleomycin injection: an observational study in superficial squamous cell carcinoma in cats Natasa Tozon, Darja Pavlin, Gregor Sersa, Tanja Dolinsek, Maja Cemazar. 2013. Journal of Feline Medicine and Surgery. Vol 16, Issue 4, pp. 291 – 299
The goal of surgery is to control or eliminate cancerous masses in an attempt to cure the patient or improve the patient’s quality of life. Surgery is the most commonly used technique to treat cancer in companion animals. Surgeons do not act in isolation and ideally are part of a comprehensive team of medical oncologists, pathologists, radiologists, criticalists, and veterinary nurses.
We work closely with your veterinarian and Veterinary Surgical Specialists. For more information please click here.
We have partnered with Torigen Pharmaceuticals. Torigen has created a targeted immunoherapy, which is patient and tumor specific. Torigen offers a for dogs, cats and horses that uses the animal’s own tumor cells to create personalized immunotherapy. It comes with a simple protocol and can be used alone or in combination with chemotherapy and radiation.
Anti-Angiogenic (Metronomic) Therapy
Anti-angiogenesis is a form of targeted therapy that uses drugs or other substances to stop tumors from making new blood vessels. Without a blood supply, tumors can’t grow. – American Medical Association
Anti-angiogenic chemotherapy generally refers to repetitive, low doses of chemotherapy designed to disrupt tumor blood vessel formation. Anti-angiogenic drugs are relatively nontoxic and work at levels well below the maximum tolerated dose. They may be given at lower doses and over longer periods of time allowing for continuous treatment of chronic disease sometimes taking weeks or even months to exhibit full benefits. Anti-angiogenic drugs may also serve as a powerful supplement to traditional chemotherapy or radiation therapy.
Tyrosine Kinase Inhibitors
Receptor tyrosine kinases are proteins that regulate cell communication and growth of new cells. Cancer causes a malfunction in these kinases, making them send abnormal signals to the cells, causing tumor growth. It is the equivalent of a light switch left on rather than turned on and off as needed.
Tyrosine kinase inhibitors (TKI’s) treat cancer by correcting this deregulation. TKI’s provide for targeted treatment of specific cancers, which lessens the risk of damage to healthy cells and increases treatment success. The most common TKI used in veterinary medicine is Palladia (Toceranib). For more information on Palladia please visit: www.mypalladia.com.
Local (Intralesional) Chemotherapy
Local chemotherapy is the administration of chemotherapy directly into a tumor or into the surgical site after the tumor has been removed. The goal is to prevent the tumor from recurring (growing back). In some cases, local chemotherapy can be given prior to surgery to make a tumor smaller for an easier and less complicated surgery. It is generally administered after surgery when all of a tumor could not be removed. Local chemotherapy kills the tumor cells left behind and can sometimes be an alternative to radiation therapy.
Zoledronate for Osteosarcoma
Osteosarcoma (OSA) of the appendicular skeleton in canines is the most common form of bone tumor. Zoledronate is a bisphosphonate that has been shown to decrease malignant skeletal destruction, severity of bone pain, and frequency of pathologic fracture. Veterinary Cancer Care participated in a research looking at the effectiveness of Zoledronate in dogs with appendicular osteosarcoma. The goals of this study were to show that zoledronate is safe, decreases bone decomposition, provides pain management, and delays metastatic disease.
For more information on zoledronate, see the following publications:
De Lorimier, L.P., and Fan, T.M. 2008. Bone metabolic effects of single-dose zoledronate in healthy dogs. Journal of Veterinary Internal Medicine, 19(6), 924- 927.
Fan, T.M, de Lorimier, L.P., and Lacoste, H.I. 2008. The bone biologic effects of zoledronate in healthy dogs and dogs with malignant osteolysis. Journal of Veterinary Internal Medicine, 22, 380-387.
Canine Melanoma Vaccine
The Canine Melanoma Vaccine is produced with a human tyrosinase gene inserted into a small ring of DNA. The vaccine alerts the immune system to the presence of melanoma tumor protein tryrosinase. When used in conjunction with surgery and/or radiation therapy, the vaccine has been shown to extend the survival time for dogs with advanced stages of melanoma. We hope for a cure when treating dogs with early stages of melanoma. Because this vaccine has been granted conditional licensure, it will only be distributed to board certified veterinary oncologists. The treatment involves one injection every other week for the first four injections. Then boosters are given at six month intervals for life.
Lymphoma Vaccine, DNA
An innovative treatment for canine B-cell Lymphoma that is given in addition to chemotherapy. Using methods similar to the melanoma vaccine, this DNA vaccine is designed to stimulate the dog’s own immune system to recognize a cell surface marker expressed in 70% of dogs with B-cell lymphoma. Once the cells are recognized as foreign, the dog’s own immune system can work to destroy them. Because this vaccine has been granted conditional licensure by the FDA, it will only be distributed to board certified veterinary oncologists. The treatment involves one injection every other week for the first four injections. Then boosters are given at six month intervals for life.
Radiation therapy is a form of cancer treatment that uses radiation (strong beams of energy) to kill cancer cells. Radiation therapy may be used in conjunction with surgery or chemotherapy to treat cancer.
Patients that require full course radiation therapy are referred to Colorado State University and can be boarded at a loving facility during their course of treatment. For more information on Colorado State University’s Animal Cancer Center please see http://www.csuanimalcancercenter.com/
External beam radiation therapy is the most common form of radiation therapy. A linear accelerator is the machine that produces beams of high-energy radiation directed at the tumor. The position of the machine is changed to aim the beams at different angles. With the use of computed tomography (CT), we can target the tumor and shield the normal tissue resulting in few side effects. When the objective is for cure, full course therapy is generally given in small fractions, Monday through Friday for 3-5 weeks. When the objective is palliative (to control pain) such as a painful bone tumor, it is given in large fractions such as once a week for three weeks.
Other treatments may be available for your pet; please contact us for more information.