Pet Medical Oncology

Oncology focuses on the treatment of cancer. In veterinary medicine, the most common treatment modality is chemotherapy but may also utilize immunotherapy or radiation therapy. The focus for veterinary oncology patients is to maintain the highest quality of life possible.

Dear Pet Owners,
We want to take this opportunity to give you insight on how our Medical Oncology functions. Our team is made up of Dr. Katelyn Marlowe, our Board Certified Medical Oncologist, along with specially trained veterinary technicians.

Our goal as a hospital is to provide the highest standard of care to all of our patients. We aim to make sure you feel confident in our ability to advocate for your pet and to help you understand and navigate the scary world of cancer and chemotherapy.

There are common misconceptions as to what chemotherapy looks like in animals. The goal in veterinary medicine is different than it is in humans, as we are aiming for remission rather than a cure. While in most cases a cure is not possible, we strive to ensure our patients have the best quality of life possible while going through their chemotherapy.

Our team of veterinarians and veterinary technicians want you to feel heard and cared for during this journey. Visits can sometimes require drop-offs or extended wait times due to the large number of cancer patients we see. We appreciate the love you have for your pets and for entrusting our team with their care.

Sincerely,
Your VCSG Oncology team

What to Expect:
At your appointment at VCSG’s Pullen Cancer Center, you will be greeted by our wonderful receptionist, who will take you into an exam room. One of our specialty trained veterinary nurses will then speak with you about the history of your pet, concerns that you may have, then they will take your pet back to our treatment area to get vitals and go over the information that was gathered for our Oncologist.

Once the Oncologist has done her full physical exam, she will speak with you about your pets diagnoses, prognoses, treatment options, and answer any questions you may have. We will be able to provide you with estimates for any treatment options and collaborate to find the best protocol that works for you and your pet.

Often, we can do same day testing, staging, and treatment as needed. At the end of your appointment we will go over discharges and follow up on any other questions or concerns you may have.

Frequently Asked Questions:

What is cancer?
– Cancer is a disease caused by the uncontrolled growth of abnormal cells in a part of the body. In some cases, this uncontrolled growth can spread to other parts of the body over time.

When do we use chemotherapy to treat animals with cancer?
– Chemotherapy may be used as the main treatment for certain cancer types, or may be used in combination with other treatments such as surgery and radiation therapy. In some cases, chemotherapy can be used to try to shrink large tumors prior to surgery or to help eliminate microscopic cancer cells that cannot or have not been completely removed surgically. For cancers that are at high risk for spread, chemotherapy can be used after surgery to help delay or prevent the appearance of cancer in other parts of the body.

How does chemotherapy work?
– Most chemotherapy drugs attack cells in the process of rapid growth. Individual drugs may work through many different mechanisms, such as damaging a cell’s genetic material (DNA) or preventing the cell from dividing properly. However, all rapidly dividing cells (including some normal ones) are potentially affected by chemotherapy. Damage to normal, rapidly growing tissues in the body is the reason for most of the side effects seen with chemotherapy. Fortunately, these tissues continue to grow and repair themselves, so injury caused by chemotherapy is rarely permanent.

What are the typical side effects of chemotherapy?
– Compared to people receiving chemotherapy, pets experience fewer and less severe side effects because we use lower doses of drugs and do not combine as many drugs as in human patients. The normal tissues that are most sensitive to chemotherapy are the intestinal lining, the bone marrow (which makes new blood cells), and occasionally hair follicles. Toxic effects to the digestive tract are responsible for decreased appetite, vomiting, and diarrhea. When observed, these signs are mild and usually resolve on their own or with oral medication given at home. Although uncommon, some animals may develop severe vomiting or diarrhea requiring hospitalization and fluid therapy. In many cases, the digestive side effects from chemotherapy are not seen on the day of treatment — occurring in some cases between 2 to 5 days later.

– Suppression of the bone marrow by chemotherapeutic drugs may cause a drop in the white blood cell count, leading to increased susceptibility to infection. Severe infections (rarely encountered) may require hospitalization for intensive supportive care, including intravenous fluids and antibiotics.

When a chemotherapeutic drug is administered that is known to have the potential for bone marrow suppression, a complete blood count (CBC) is checked before the treatment is given and at a predetermined time after a chemotherapy dose (usually 7-10 days). If the white blood cell count is low but your pet is feeling well, treatment may be postponed and antibiotics prescribed as a preventative measure. Subsequent doses of chemotherapy may be reduced.

Hair follicle cells in dogs that are wire-haired or non-shedding may be particularly susceptible to chemotherapy. Certain breeds of dogs, such as terriers and poodles, will experience variable amounts of hair loss.

There are many different types of chemotherapy agents and each has a different likelihood of causing side effects. If your pet is treated with chemotherapy drugs known to cause certain side effects, Dr. Marlowe will prescribe medications to help prevent these complications (such as anti-nausea medications).

We will also give you instructions on what to do in the case of a severe reaction to chemotherapy. We seldom see severe side effects; it is estimated to be less than 5% of all pets receiving chemotherapy. With proper management, most animals recover uneventfully within a few days. Please keep in mind that any animal can have an unexpected reaction to any medication.

How is chemotherapy administered?
– How a chemotherapeutic drug is administered, how often it is given and how many treatments are given varies from case to case. The type of cancer, the extent of disease, and general health of the patient help the oncologist to formulate a treatment protocol (type of drugs, dose, and schedule used) appropriate for your pet.

Some chemotherapy medications are administered orally (pills), and can be given at home. Others are brief injections that require an outpatient appointment. In a few instances, slow infusions or repeated treatments throughout the day may require an animal to spend the day in the hospital.

Treatments are typically repeated from weekly to every third week. Blood tests may be needed to monitor the effects of chemotherapy during the weeks between drug treatments.

– The duration of chemotherapy depends on the type of cancer and the extent of disease. Certain animals may need to receive chemotherapy for the rest of their lives. In others, treatments may be spread out or discontinued after a period of weeks to months provided that the cancer is in remission, i.e., there is no detectable evidence of cancer in the body. Chemotherapy can be resumed if the cancer relapses.

– We usually recommend that every patient receive at least 2 cycles of chemotherapy and then be evaluated for response before the decision is made to continue the course of treatment, change drugs or discontinue chemotherapy.

What can be expected from chemotherapy?
-In many cases, we are unable to cure our veterinary cancer patients. Our goal is therefore to maintain a pet’s quality of life while trying to prolong survival. To this end, chemotherapy can sometimes be used to minimize the discomfort caused by a tumor, or to slow down or stop the progression of the disease. For most (but not all) types of tumors, the oncologist will provide information on expected outcomes with and without treatments. The decision of whether to pursue chemotherapy for your pet can be complex. Medical information, practical concerns (such as need for repeated visits, your pet’s temperament, etc.), and financial responsibility all play a part in this decision. We encourage you to discuss your concerns with the oncologist and your regular veterinarian when making this decision.

Handling Chemotherapy at Home
– Chemotherapy drugs have the potential to cause damage to normal cells. Exposure to chemotherapy drugs or patient waste can pose a risk, despite the fact that the concentrations of drugs are very low. This risk is greatest for those people who are pregnant or nursing.

If you are administering chemotherapy pills at home, it is suggested that you wear disposable latex gloves when handling the pills, and that tablets not be broken or crushed, nor capsules opened. Certain chemotherapy drugs and their by-products may be excreted in the feces or urine for up to 96 hours following administration. The risk associated with exposure is slight; however, should your pet have an accident in the house, it is wise to wear disposable rubber or latex gloves, blot the area with flushable paper, and clean the area twice with a detergent solution.

There is no real risk associated with routine contact with your pet such as grooming, playing, or handling of food and water bowls. It is important that these medications be kept out of the reach of children. Should accidental ingestion of chemotherapeutic drugs occur, contact a poison control center immediately. Should any unused chemotherapy drugs remain after treatment, please return them, so that they can be disposed of safely.

Commonly Treated Conditions:

• Lymphoma
• Osteosarcoma
• Mast Cell Tumors
• Mammary Gland Carcinoma
• Thyroid Carcinoma
• Leukemia
• Squamous Cell Carcinoma
• Soft Tissue Sarcoma
• Transitional Cell Carcinoma
• Malignant Melanoma
• Multiple Myeloma
• Histiocytic Sarcoma
• Salivary Gland Carcinoma
• Anal Gland Adenocarcinoma

Treatment Options:
We offer a wide variety of treatment options/protocols that can be customized to better fit your pet and family needs:

• Injectable chemotherapies
• Oral chemotherapies
• Staging- radiographs, ultrasounds, cytology, and biopsies
• Stelfonta injections to treat Mast Cell Tumors
• Melanoma vaccines
• Palliative care options
• Collaborative approach that can offer different treatment options such as; Radiation Oncology, Surgical, Internal Medicine, and Neurology consults