VCA ASEC offers comprehensive cancer therapy management by full-time board-certified oncologist, Dr. Sue Downing, including consultations exploring the prognosis and options following cancer diagnosis. Evaluation of the cancer patient incorporates discussion of the tumor behavior, review of tests previously completed, further disease staging and printed materials for review at home. The optimal treatment plan will be presented along with other available options and palliative care, reviewing effectiveness, time involved, side effects, and cost of treatment. Therapies include chemotherapy using novel agents and protocols, immunotherapy, hospice care and pain management.

Common Cancers in Pets:


For other types of cancer, please refer to the Veterinary Society of Surgical Oncology website.

Frequently Asked Questions

Just as in people, there is no proven way to keep your pet from getting cancer. You can, however, take steps to minimize the risks. Avoid any known predisposing causes, such as not spaying or neutering pets, or leaving pets exposed to sunlight. Also make sure your pet has regularly scheduled checkups and follow your veterinarian's advice regarding any necessary screening tests.

Any veterinarian who wants to specialize in oncology must first be certified as an internal medicine specialist. Veterinarians who want to become board certified in internal medicine must seek additional, intensive training to become a specialist and earn this prestigious credentialing. Specialty status is granted by the American College of Veterinary Internal Medicine (ACVIM). A veterinarian who has received this specialty status will list the initials, 'DACVIM,' after his or her DVM degree. Or, the veterinarian may indicate that he or she is a 'Diplomate' of the ACVIM. The word 'Diplomate' typically means the specialist has achieved the following:

  • Obtained a traditional 8 year veterinary degree (four years of college plus four years of veterinary school).
  • Completed an additional three to six years of advanced training, including a residency at a veterinary teaching hospital where the veterinarian will have trained with some of the best experts in the field and obtained hands on experience.
  • Completed the credentialing application process established by the ACVIM
  • Passed a rigorous general examination.

Once a veterinarian is board certified in internal medicine, he or she may seek additional specialty status in veterinary oncology. Internal medicine specialists must obtain additional training in this area and sit for a second, even more intensive examination. These doctors will list their credentials after their boarded status, for example, as 'DAVCIM (Oncology).'

When your pet needs the care of a veterinary internal medicine specialist/veterinary oncologist, years of intensive training and additional education will be focused on helping him or her to recover from the disease and/or enjoy the highest quality of life possible.

The goal of cancer therapy is to destroy abnormal cancer cells while sparing normal cells. An important difference in human vs. animal oncology is that the goal with humans, due to our extended life spans, is to cure the disease. In animals, the goal is more to extend the length of life while still maintaining its
quality. In many cases, a veterinary oncologist will combine some or all of the treatment options outlined below in order to provide the very best outcome for your pet.

  • Surgery
  • Radiation Treatment
  • Chemotherapy
  • Immunotherapy

Your veterinary oncologist will give you specific instructions regarding your pet's chemotherapy, but in general, you should be aware that pets typically handle chemotherapy regimens far better than people do. First, as cancer treatment for both humans and small animals has become more sophisticated, the side effects created by chemotherapy regimens have become less severe. Second, chemotherapy administration in animals is less aggressive than it is in humans, so animals typically do not become as sick from the side effects as do people.

Finally, veterinary oncologists have many options at their disposal to help keep your pet comfortable during treatment for his or her disease. From pain management options to special nutritional recommendations to medications that can help lessen the nausea associated with chemotherapy, be assured that veterinary oncologists can keep most pets surprisingly comfortable during treatment. In fact, one of the biggest hurdles to treating pets with cancer is that many owners imagine their pet's treatment will be more difficult than it really is.

Adenocarcinoma: cancer that develops from glandular tissue, such as salivary gland

Adjuvant therapy: treatment used in addition to surgery, such as chemotherapy, radiation therapy, or immunotherapy, to improve the prognosis

Adjuvant chemotherapy: the use of chemotherapy to prevent the growth and spread of cancer that is not detected but is judged to possibly be present after surgery and/or radiation therapy

Anemia: low red blood cells, resulting in low oxygen delivery throughout the body; anemia may result from blood loss and/or from decreased red blood cell growth in the bone marrow. Signs and symptoms of anemia may include: fatigue, weakness, pale gums, reduced appetite, and/or rapid breathing.

Anorexia: loss of appetite; anorexia may be caused by the presence of a tumor or by treatments such as chemotherapy

Antidote: remedy used to neutralize or counteract the effects of a toxin (such as chemotherapy)

Aspirate: to draw out liquid or tissue using a needle to be looked at under a microscope

Benign: tumor that that is not cancer and does not spread to other areas of the body, e.g. lipoma, a benign fatty tumor

Biopsy: to obtain a tissue sample and examine for the presence or absence of cancer cells

Bone marrow: the spongy tissue contained within the hollow center of certain bones where new blood cells are made

Cachexia: extreme weight loss and wasting away caused by malnutrition and/or the growth of the malignant tumor

Cancer: a group of diseases that are characterized by the uncontrolled and abnormal growth of cells

Carcinogen: cancer-causing agent that causes mutations in cells, leading to uncontrolled growth of these cells and tumor formation. For example, tobacco contains many carcinogens that greatly increase the risk of lung cancer and other types of cancer.

Carcinoma: cancer that develops from epithelium, a tissue that covers/lines organs. The skin, trachea or bronchi, oral cavity, prostate, bladder, and mammary gland are common sites of carcinomas in the dog and cat.

Chemotherapy: drugs used to treat cancer, commonly referred to as "chemo." Most chemotherapy drugs work either by damaging DNA or RNA of the cancer cell or by blocking some function of the cancer cell.

Chemotherapy resistance: lack of responsiveness of cancer cells to some or all chemotherapy drugs. Chemotherapy resistance may result from cancer cells developing the ability to prevent or heal damage caused by drugs or it may be present in a tumor even before chemotherapy drugs have ever been administered.

Complete blood cell count (CBC): a blood test to determine the number of red blood cells, white blood cells, and platelets

Computed tomography (CT or CAT) scan: a medical imaging procedure that uses x-ray and a computer to produce a series of detailed pictures of an area of the body, viewed as cross-sectional “slices”

Cycle: a repeating series of one or more chemotherapy drugs given at regular intervals

Cystitis: inflammation or infection of the inner lining of the urinary bladder

Cytology: microscopic examination of cells collected by swab or aspiration; a screening test to determine if cancer may be present

Debulk: to surgically reduce the amount of cancer by removing all that can be safely taken without compromising the patient

Diagnosis: the identification of a specific disease, through evaluation of patient history, examination, and review of laboratory tests. A diagnosis of cancer requires microscopic examination of blood or tissue.

Edema: buildup of fluid in the tissues, causing swelling

Excisional biopsy: a surgical procedure to attempt removal of the entire tumor. After an excisional biopsy is performed, the tissue is submitted to a pathologist for diagnosis and to confirm whether any tumor tissue was left behind

Gastrointestinal tract:
the digestive system, which includes the mouth, esophagus, stomach, small intestine, colon, and rectum; also called the GI tract or the digestive tract

Grade: a microscopic classification of a tumor designed to predict the behavior of the cancer. Low-grade is generally associated with less aggressiveness and a slow growth pattern, and high-grade suggests very aggressive behavior with rapid growth and spread.

Histopathology: the microscopic examination of abnormal or diseased tissue to make a diagnosis

Hospice: prevent suffering at end of life and help the patient enjoy life to the fullest and to remain with family as long as possible until a natural death occurs or euthanasia is chosen

Immunotherapy: treatment of cancer by stimulating the immune system to reject and destroy tumor cells. An example if immunotherapy is the vaccine is currently used to treat melanoma in dogs.

Incisional biopsy: a surgical procedure to remove a small piece from a tumor for diagnosis. Incision biopsy is performed when removal of an entire tumor is impossible or its removal could significantly compromise the patient.

Induction chemotherapy:
the first-line treatment with chemotherapy in which higher doses and/or more types of drugs are used to kill as many tumor cells as quickly as possible

Intravenous (IV): administered into a vein, directly into the blood stream

cancer of the bone marrow that is characterized by the abnormal growth of blood cells

Lymph node:
small gland containing immune system tissue located throughout the body to remove cell waste and harmful substances from lymph; also known as lymph glands. Lymph nodes help fight infections and also have a role in fighting cancer, although cancers can spread into lymph nodes.

Lymphocyte: a specific type of white blood cell that identifies foreign agents and generates an immune system response

Lymphoma: cancer of the lymphocyte cells or other lymphoid tissue, also known as lymphosarcoma

Lymphosarcoma: see “lymphoma”

Malignant or Malignancy:
cancer with the ability to invade locally in an uncontrolled fashion and spread throughout the body

tissue removed beyond the visible edge of a tumor in an effort to eliminate all of the cancer. A negative surgical margin means that no cancer cells were found on the outer edge of the removed tissue, and is considered a sign that none of the cancerous mass was left behind. A positive surgical margin means that cancer cells are found at the outer edge of the tissue removed and is usually a sign that some cancer remains in the body.

Mast cell tumor: a common tumor in the dog that is usually located in the skin. Mast cells contain histamine, which can cause the tumor to swell and itch.

Medical oncologist: a medical specialist who is trained to diagnose cancer and prescribe a rational course of treatment. Medical oncologists are involved with the administration of chemotherapy; they also often recommend surgery or radiation therapy, procedures that are usually performed by other specialists.

Melanoma or Melanosarcoma: cancer of the pigmented cells of the skin and mouth, common in the dog but rare in the cat

Metastasis: spread of cancer from its original site to other parts of the body, usually through the blood or lymph vessels

Myeloma: cancer of the antibody-forming blood cells, known as plasma cells

decreased production of white blood cells, red blood cells, and platelets in the bone marrow, caused by chemotherapy

Nadir: a temporary low blood cell count caused by a chemotherapy treatment

Neoplasm or Neoplasia (plural): a growth of any new or abnormal cells or tissue in the body. A neoplasm may be benign (not cancer) or malignant (cancer).

Neutropenia: a decrease in the number of neutrophils, the white blood cells that respond to infection

Oncologist: a medical specialist with advanced training in the diagnosis and treatment of cancer

Oncology: the medical science of the diagnosis and treatment of cancer

Osteosarcoma: a malignant cancer of bone cells

Palliative: treatment to decrease the severity of symptoms without the intention to cure, most often focused on issues such as reducing pain or bleeding. The main purpose of palliative care is to improve the patient’s quality of life.

Pathologist: a medical specialist who examines tissue samples to diagnose and classify diseases

Platelets: blood cells that assist in the formation of a blood clot, helping to stop bleeding

Primary tumor: the organ or location where the first tumor cells began to grow in a patient’s body. Cancer is named after the organ in which it begins. For example, cancer that starts in the breast is always breast cancer, even if it spreads (metastasizes) to other organs such as bones or lungs.

Prognosis: a prediction of the course of disease, either with no treatment or for various treatment options. Prognosis is based on the type of tumor, the stage, the grade, the available treatments and other factors such as the patient’s overall health.

Prophylactic: treatment used to assist in the prevention of symptoms or disease

Protocol: a plan or “recipe” of chemotherapy drugs including the doses and the schedule for administration of each drug

Radiation oncologist: a medical specialist who plans, prescribes, and administers radiation therapy for the treatment of cancer

Radiation therapy or Radiotherapy: use of high-energy radiation to treat cancer, either by killing cancer cells or preventing further cell division

Red blood cells (RBC): blood cells that circulate throughout the body to supply oxygen to tissues

Relapse: reappearance of cancer or other disease after a disease-free period

Remission: complete or partial disappearance of the signs and symptoms of cancer in response to treatment. Remission does not necessarily mean a cure, since a few microscopic cells may remain and the cancer may ultimately recur.

Sarcoma: cancer that develops from connective tissue, such as cartilage, fat, muscle, or bone

Spindle cell: a cell with the appearance of a long oval when viewed under a microscope, typical of sarcomas and some melanomas

Stage: the extent of a cancer throughout a patient’s body, including invasion of a tumor into bone or other surrounding tissue, involvement in lymphatics and lymph nodes, and spread into other organs

Staging: a series of diagnostic tests used to determine the extent of spread of cancer

Subcutaneous (SQ, SC or SubQ): under the surface of the skin

Systemic disease: cancer that present in distant organs or structures

Thrombocytopenia: a decrease in the number of platelet cells in the blood. Severe thrombocytopenia can result in an increased risk of bleeding.

Tumor: an abnormal lump or mass of tissue. Tumors can be benign (not cancer) or malignant (cancer).

White blood cells (WBC): cells that circulate in the blood and tissues to fight infection and make antibodies. There are several types of white blood cells including neutrophils and lymphocytes.

high-energy radiation that is used in low doses to create diagnostic images and in high doses to treat cancer

For additional terms, please refer to the American Cancer Society Cancer Glossary:
American Cancer Society Cancer Glossary

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