While not many pet owners may realize it, the good news is that are a range of treatment options available for our veterinary cancer patients. Friendship has many years of experience helping thousands of pets fight cancer, with the goal of either improving an animal’s quality of life, or in the best case, achieving a long-term outcome. The type of treatment depends on the underlying tumor type, whether or not the tumor has spread, and what is in the best interest of the patient. Veterinary oncology focuses on good patient quality of life while still providing the optimal care.
Surgery is the best chance to provide a long-term outcome for our patients. For some tumor types, this may be the only treatment needed. Surgery is most successful with solitary tumors that have not spread distantly to other parts of the body. These typically include carcinomas (cancer of cells that line body cavities or organs), sarcomas (cancer of connective tissue), and some other solid tumors. A key first step is to screen for whether the cancer has spread (gone metastatic), as surgery is not likely to be an option if a tumor has already spread.
Chemotherapy describes drugs used to kill cancer cells, typically, by damaging DNA in rapidly dividing cell populations. Cancer cells typically divide more quickly compared to normal cells in the body, and therefor may be more responsive to chemotherapy than normal cells. Chemotherapy is recommended for a number of reasons: to achieve a remission (ex. Lymphoma); to “shrink” widespread disease; or following surgery or radiation to decrease the chance that a cancer spreads or regrows. Less commonly, it is used prior to surgery or radiation to make a tumor more amenable to localized treatment. Chemotherapy can be administered intravenously or orally, either in the hospital or at home.
But what about chemotherapy side effects?
But what about chemotherapy side effects? Although side effects are possible, there is a relatively low risk in veterinary patients. Our main goal is quality life, and if this is compromised by our treatments, we will change the dosing scheme or come up with an alternative plan. We typically use lower doses when compared to many human chemotherapy protocols, and approximately 80% of patients will not experience any significant side effects. If we do see side effects, they are often gastrointestinal related, with about 10-20% experiencing decreased appetite, vomiting, or diarrhea. All patients are sent home with medications to help prevent or decrease these effects should they occur. There is a low (<5%) risk of bone marrow suppression. This means a decrease in an animal’s white blood cell count (or other cell lines), putting patients at risk for widespread infection requiring hospitalization. Blood work is checked prior to each treatment to make sure it is safe to administer chemotherapy. Other drug-specific side effects include cardiotoxicity, liver damage, lung damage, and rarely hair-loss in certain breeds.
Radiation therapy (RT) is a localized therapy that can be effective for controlling a wide range of tumors in pets. Currently, Friendship does not have the ability to do radiation, but we work closely with radiation oncologists in the region to provide the best treatment plan for each patient. Each treatment requires brief periods of anesthesia, as the patient must be very still while the radiation is administered. Radiation may be used alone or in combination with other cancer therapies (surgery/chemotherapy). Although not currently available at Friendship, RT is readily available to large segments of the veterinary profession with many locations in U.S., Europe, and Australia. We can refer to nearby facilities should the need for radiation arise for your pet. There are a number of types of radiation, and the recommended protocol is based on the type of tumor involved, and what is best for your pet. Some protocols are used to provide definitive tumor control, while others are used to provide comfort and pain control. Friendship hopes to have the ability to offer radiation in the near future.
Immunotherapy, is a broad term used to describe treatments that stimulate the immune system to fight cancer (and other diseases). While these treatments are more readily available in human medicine, there are some cancers in veterinary medicine that may respond to this therapy. For example, the Oncept Melanoma vaccine was developed to help fight canine malignant melanoma. If there is an option for immunotherapy, this is always discussed with the patient’s owner, to maximize the best treatment options for each pet.
Last, but certainly not least, palliative care, is an extremely important part of veterinary cancer treatment. This involves the use of pain medications, and treatment of other symptoms (ex. nausea, inflammation) to keep patients as comfortable as possible. These therapies may be used alone in patients with advanced disease or where the above therapies are not feasible. They may also be combined with more traditional treatments to maximize patient comfort and outcome.
Have more questions about your pet’s cancer and possible treatment options?
Feel free to set up a consultation with a Friendship oncologist to discuss the best treatment plan for your pet.
Dr. Foskett is a Diplomate of the American College of Veterinary Internal Medicine (Oncology). She graduated from Duke University, where she double-majored in French studies and Biology with a focus in marine biology. She attended veterinary school at the University of Florida before completing a 1-year rotating internship at Friendship, followed by a 3-year medical oncology residency program with The Oncology Service.