For decades, the three-part approach to treating cancers in people and animals has included chemotherapy, radiation and/or surgery, depending on the nature of the illness. In recent years, however, cancer treatments for pets have been refined. These breakthroughs give owners a number of options they haven’t had before.

Types of Pet Cancer Treatments for Pets

Radiation and surgery may not be the best options for one of several reasons. These reasons could include the age or general health of the animal. Or the cancer may be difficult for a surgeon to completely and safely remove, or the cancer is systemic.

So, in this article, we’re going to talk about approaches to cancer treatment that don’t involve radiation or surgery: oral chemotherapy, intralesional chemotherapy, immunotherapy and palliative care.

Oral chemotherapy

Though some patients believe oral chemotherapy attacks cancer less rigorously than intravenous chemotherapy, that’s not true. And it has a distinct advantage: Owners can sometimes administer medication at home, bringing a pet to the clinic sporadically for blood work that lets doctors monitor the cancer and the drug’s side effects on the body.

Cats may need a pill as infrequently as once a month. Another oral option is metronomic chemotherapy, low-dose administration of pills (generally every day) without prolonged drug-free breaks. That’s an especially effective treatment for sarcomas.

Intralesional chemotherapy

Intravenous chemotherapy goes into a vein and targets rapidly dividing cancer cells anywhere in the body. But the rarer intralesional chemotherapy, which CARE offers, uses a needle to place medicine directly under a scar where a cancer has been removed.

That may be necessary if the removal of a skin tumor leaves margins margins that are “dirty” (in veterinary parlance) where cancer can remain at the cellular level. Many intralesional treatments attack subcutaneous tumors or soft-tissue sarcomas.

According to the Veterinary Cancer Society, one in four dogs will be diagnosed with cancer at some point. One-fourth of those cancers will be lymphoma, the most common cancer in dogs. Last year, Tanovea became the first drug fully approved by the FDA to treat lymphoma in dogs, attacking it at the cellular level. (Similar studies have not been performed on cats, which get this disease much more rarely.)


Immunotherapy supercharges a patient’s immune cells to attack cancer cells. CARE’s flagship treatment of this type, the melanoma vaccine, trains the immune system to recognize melanoma cells as foreign and kill them. (Melanoma, the most common oral cancer, develops in cells that produce the pigment that creates skin color.)

Given in a muscle, not under the skin as with most vaccines, pets get them four times, two weeks apart. Boosters follow every six months. This kind of treatment can keep the disease at bay and may give the pet a natural lifespan, but does not cure it.

Palliative care

Owners may associate this phrase with untreatable diseases. But vets use it to mean making patients comfortable and maintaining high quality of life. They may address symptoms with medication, refer patients to outside vets who do pain-relieving acupuncture, or find vets who specialize in integrative medication that involves supplements or a holistic approach.

For example, a dog with a benign nasal lesion might require management of his bleeding and inflammation, because nasal surgery isn’t an option. A pet with an inoperable stomach tumor (benign or malignant) may get pain medications. Other options might include anti-nausea medications, appetite stimulants and intravenous fluids to stay hydrated.

The oral tablet Laverdia was also conditionally approved by the FDA last year. Vets might likely prescribe it to maintain quality of life for owners who don’t pursue chemotherapy because of its expense, the age of the animal, or the difficulty in administering chemo to an aggressive pet.

Breakthroughs in cancer treatments for pets are happening more often as new treatments gain traction. Also, more than ever before, we understand what kind of outcomes we can expect. If your pet develops cancer, the oncology team at CARE can help you understand your options. Together we can chart a course most likely to provide the best quality of life for the longest time.

Think of CARE as the animal version of a medical center for humans. It provides all forms of treatment for pets through emergency care 24 hours a day, 365 days a year, and it offers board-certified specialty care after a referral from your primary veterinarian. You can take a visual tour of the practice at

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